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Cad-Vt} ‘ “ ‘ " W" 7‘ Lth'. . “E?“fi‘ we ‘3 35.3% "“ 1v; ”av-"W" é 431:??? . '0'» v ,‘g}.'.£‘. 1. 'in'J.‘ mag flcfi' 4 1I§E\Q%b UNIVERSITY LIBRARIES IIIIIIIIIIIIIIIIIIIIIIIIII I II III I I m— 31293005514512 LIBRARY Michigan State University I This is to certify that the thesis entitled ABSORPTION OF ORGANIC VOLATILES BY SEALANTS FILMS presented by TAKAYUKI IMAI has been accepted towards fulfillment of the requirements for M.S. PACKAGING degree in fl) (ax/(4%? 3‘4 W Drs. Bruce R. Harte 8 Jack Giacin Major professor (5) Date June ”I, I988 0-7639 MS U is an Affirmative Action/Equal Opportunity Institution MSU RETURNING MATERIALS: Place in book drop to LJBRARJES remove this checkout from .—_—. your record. FINES W'iII be charged if book is returned after the date stamped below. iiu 2 tr? ** . .- _ A“ . frat a7 ’53 III 01‘: 9 II .2 Fifi 32:13 was ABSORPTION OF ORGANIC VOLATILES BY SEALANT FILMS BY Takayuki Imai A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE School of Packaging 1988 'g/ ABSTRACT ABSORPTION OF ORGANIC VOLATILES BY SEALANT FILMS BY Takayuki Imai The absorption of organic volatile compounds by plastic films was investigated, and the influence of the absorption of these compounds on the mechanical properties of the plastic films as a function of sorbed concentration levels was evaluated. Sample strips of polyethylene (LDPE), ethylene vinyl alcohol copolymer (EVOH) and co-polyester (Co- PET) were immersed in juice. Absorption of d-limonene by Co- PET was significantly lower in comparison to that of the other two films. The sorption of d-limonene by plastics affected the (a) modulus of elasticity (EVOH, Co- PET), (b) yield stress (EVOH), (c) stress at 100 % elongation (LDPE, EVOH), (d) heat seal strength (LDPE), and (e) impact resistance (EVOH, LDPE). The plastics varied their properties due to sorption of flavor component. ACKNOWLEDGMENTS I would like to express sincere thanks and appreciation to: Dr. Bruce R. Harte, Associate Professor in the School of Packaging and my major advisor, for his kind counsel and assistance throughout the course of this graduate program. Dr. Jack R. Giacin, Professor in the School of Packaging, for being a committee member and his professional advice throughout my research. Dr. Ian J. Gray, Professor in the Department of Food Science and Human Nutrition, for being a committee member and donation of time. Dr. Heidi Hoojjat, Mr. James Konczal and Mr. Cheng- Hsiling Chen for the sharing of knowledge and skills. I also acknowledge film samples and financial support for this study provided by 8.1. DuPont De Nemours & Company, and TOPPAN Printing Co., Ltd., who made this graduate work possible, for their continued support. '...| (ON TABLE OF CONTENTS LIST OF TABLES ————————————————————————————————————— LIST OF FIGURES ------------------------------------ INTRODUCTION --------------------------------------- LITERATURE REVIEW ---------------------------------- 4-1. Carton Style Aseptic Packaging --------------- Shelf — Life of Aceptically Packed Juice ----- .5 tom . Package Interaction -------------------------- 4.4. Analytical Methods for Flavor Analysis (Limonene) 4.5. Effect of Water Sorption on Mechanical and Pysical Properties --------------------------- 4.6. Effect of Organic Vapor Sorption on Mechanical and Physical Properties ---------------------- MATERIALS AND METHODS —————————————————————————————— 5.1. MATERIALS ------------------------------------ 5.2. EXPERIMENTAL METHODS _________________________ 5.2.1. Quantitative Analysis of Aroma Compounds 5.2.1.1. The Bromide-Bromate Titration - 5.2.1.2. Gas Chromatographic Analyses -- 5.2.2. Recovery of Aroma Compounds by Distillation 5.2.3. Determination of d-limonene in Orange Juice 5.2.4. Storage Stability of Orange Juice ------- iv 16 18 21 21 22 22 22 23 26 26 5.2.5. Extraction Method of Aroma Compounds from Plastic Films ----------------------- 5.3. IMMERSION STUDY - Mechanical Properties 5.3.1. 5.3.2. Mechanical Properties of Plastic Films 6. RESULTS AND DISCUSSION 6.1. Recovery of Aroma Compounds by Distillation 6.2. Storage Stability of Orange Juice 6.3. Extraction of Aroma Compounds from Plastic Films 6.4. Immersion Studies 6.4.1. 6.4.2. Influence of d-Limonene Absorption on Mechanical Properties of Plastic Films 7. CONCLUSION Sorption Measurement ---------------- 5.3.2.1. Stress - Strain Properties 5.3.2.2. Impact Resistance --------- Sorption Measurements --------------- Page 29 30 30 32 32 38 38 41 41 47 47 6.4.1.1. Distribution of d-limonene between juice and plastic films 6.4.1.2. Partition Coefficient 6.4.2.2. Impact Resistance --------- 1. Modulus of Elasticity 2. Yield Stress --------- 3. Stress at 100 percent elongation ----------- .4. Tensile Strength ---------- 5. 6 Elongation at Break Heat Seal Strength ----- 119 8. APPENDICES ---------------------------------------- I. II. III. IV. v. VI. STANDARD CALIBRATION ------------------------ The Components of the Preservatives --------- The Sample Correlation Coefficient ---------- Desorption of d-Limonene from ALATHON ®>1645 (LDPE) Film _________________________________ One-Way Analysis of Variance ———————————————— Determination of Impact Failure Weight ------ 10. BIBLIOGRAPHY ------------------------------------- vi Page 121 121 130 132 133 138 147 151 LIST OF TABLES Table Page 1 Manufacturers of aseptic, carton systems --------- 4 2 The contribution of volatiles to orange juice flavor 11 3 Regents used in the microbial growth study ------- 28 4 The weight of sample films ----------------------- 31 5 Film sample size and film area / to juice volume ratio -------------------------------------------- 35 6 Film heat sealing conditions --------------------- 36 7 Test conditions for film stress - strain evaluation 37 8 Percent recovery of d-limonene from a standard d-limonene solution using the distillation technique .39 9 Percent recovery of neral and geranial from standard solutions using distillation technique ----------- 4O 10 D-limonene concentration in the orange juice containing antioxidand and antimicrobial agents -- 42 11 Microbial stability of orange juice containing antimicrobial agent, stored at 25%: -------------- 42 12 Measurement of d-limonene and geranial sorbed by HDPE and extracted using different solvents ------------ 43 13 The amount of d-limonene in the HDPE extracted using IPA with distillation ----------------------------- 44 14 Limonene concentration in the films measured from using different analytical methods ---------------- 46 15 Change in d-limonene concentration in orange juice during storage at 21°C, following contact with test films --------------------------------------------- 48 vii Table page 16 17 18 19 20 21 22 23 24 25 26 27 28 2,9 30 31 Relative percent of d-limonene remaining in the juice during storage at 219C, following contact with test films ---------------------------------------- 49 ANOVA table for d-limonene concentration in the control juice sample ------------------------------ 51 ANOVA table for d-limonene concentration in the juice containing ALATHON ® LDPE strips ----------------- 54 ANOVA table for d-limonene concentration in the juice containing SELAR ® EVOH strips -------------------- 55 ANOVA table for d-limonene concentration in the juice containing SELAR ® Co- PET strips ----------------- 56 ANOVA table for d-limonene concentration in the juice containing different sample strips ---------------- 57 The amount of d—limonene soebed by the sample films, following immersion in orange juice, at 219C ------ 59 The partition coefficients values for d-limonene, and the orange juice/polymer contact film systems ----- 63 Change in modulus of elasticity for the ALATHON ®ILDPE film immersed in orange juice during storage at 21%: 67 Statistical evaluation of the change in modulus of elasticity for ALATHON ® LDPE film ----------------- 68 Change in modulus of elasticity for SELAR @IEVOH film immersed in orange juice during storage at 219C --- 69 Change in modulus of elasticity for SELAR ®ICo-PET A film immersed in orange juice during storage at 21%: 70 Statistical evaluation of the change in modulus of elasticity for SELAR ® EVOH film ------------------ 71 Statistical evaluation of the change in modulus of elasticity for SELAR ® Co-PET film ----------------- 72 Change in yield stress for ALATHON ® LDPE film immersed in orange juice during storage at 219C --- 78 Statistical evaluation of the change in yield stress for ALATHON ® LDPE film --------------------------- 79 viii Table Page 32 33 34 35 36 37 38 39 4O 41 42 43 44 45 46 47 Change in yield stress for SELAR ®>EVOH film immersed in orange juice during storage at 219C --- 80 Statistical evaluation of the change in yield stress for SELAR ® EVOH film ----------------------------- 81 Change in stress at 100 percent elongation for ALATHON ® LDPE film immersed in orange juice and stored at 21%: ------------------------------------ 84 Change in stress at 100 percent elongation for SELAR ® EVOH film immersed in orange juice and stored at 219C ------------------------------------ 85 Statistical evaluation of the change in stress at 100 % elongation for ALATHON ® LDPE and SELAR ® EVOH films 86 Change in tensile strength for ALATHON ® LDPE film immersed in orange juice during storage at 219C --- 89 Statistical evaluation of the change in tensile strength for ALATHON ® LDPE film ------------------ 90 Change in tensile strength for SELAR ® EVOH film immersed in orange juice during storage at 219C --- 91 Change in tensile strength for SELAR ®>Co-PET film immersed in orange juice during storage at 219C --- 92 Statistical evaluation of the change in tensile strength for SELAR ® EVOH film -------------------- 93 Statistical evaluation of the change in tensile strength for SELAR ® Co-PET film ------------------ 94 Percent elongation at break for ALATHON ®>LDPE film immersed in orange juice during storage at 219C --- 99 Statistical evaluation of the change in elongation at break for ALATHON ® LDPE film --------------------- 100 Percent elongation at break for SELAR GIEVOH film immersed in orange juice during storage at 219C --- 101 Percent elongation at break for SELAR ®>Co-PET film immersed in orange juice during storage at 219C --- 102 Statistical evaluation of the change in elongation at break for SELAR ® EVOH film ----------------------- 103 ix Table Page 48 Statistical evaluation of the change in elongation at break for SELAR ® Co-PET film ------------------ 104 49 Heat seal strength for ALATHON ® LDPE film immersed in orange juice during stirage at 219C ------------ 109 50 Statistical evaluation of the change in heat seal strength for ALATHON ® LDPE film ------------------ 110 51 Heat seal strength for SELAR GIENOH film immersed in orange juice during storage at 219C ------------ 111 52 Heat seal strength for SELAR ®ICO-PET film immersed in orange juice during storage at 219C ------------ 112 53 Statistical evaluation of the change in heat seal strength for SELAR ® EVOH ------------------------- 113 54 Statistical evaluation of the change in heat seal strength for SELAR ® Co-PET film ------------------ 114 55 Influence of sorption on impact resistance of the sample films -------------------------------------- 117 56 Limonene Standard Calibration Curve Data: G.C. Model #5830 equipped with the packed column -- 122 57 Limonene Standard Calibration Curve Data: G.C. Model #5890 equipped with the capillary column - 124 58 Neral and Geranial Standard Calibration Curve Data: G.C. Model #5890 equipped with the capillary column 127 59 Desorption of d-limonene and geranial from ALATHON 3’ LDPE film ----------------------------------------- 135 60 ANOVA table for comparing k treatment ------------- 139 61 ANOVA table for modulus of elasticity ------------- 141 62 ANOVA table for yield stress ---------------------- 142 63 ANOVA table for stress at 100 percent elongation -- 143 64 ANOVA table for tensile strength ------------------ 144 65 ANOVA table for elongation percent at break ------- 145 66 ANOVA table for heat seal strength ---------------- 146 Table 67 68 69 Impact failure weight of ALATHON ® LDPE film Impact failure weight of SELAR ® EVOH film -- Impact failure weight of SELAR ® Co- PET film xi LIST OF FIGURES Figure Page 1 Per annum Consumption of Fruit Juices by Juice Types 7 2 Growth of Aseptic Packages ------------------------ 8 3 Relationship between modulus of elasticity and temperature as a function of a moisture on Nylon 6 l9 4 Relationship between yield stress and temperature as a function of moisture sorbe by on Nylon 66 --—— l9 5 Oxygen Barrier Properties ------------------------- 20 6 D-limonene concentration in the orange juice as a function of storage time for different films ------ 50 7 The sorption of d-limonene by the films as a function of storage time ----------------------------------- 60 8 Relationship between modulus of elasticity and d-limonene concentration for SELAR ®>EVOH film ---- 73 9 Relationship between modulus of elasticity and d-limonene concentration for SELAR ®>Co-PET film -- 74 10 Relationship between modulus of elasticity and d-limonene concentration for the test films (MD) -— 75 11 Relationship between modulus of elasticity and d-limonene concentration for the test films (CD) -— 76 12 Relationship between yield stress and d-limonene concentration for ALATHON ® LDPE film ------------- 82 13 Relationship between yield stress and d-limonene concentration for SELAR ® EVOH -------------------- 83 14 Relationship between stress at 100 % elongation and d-limonene concentration for ALATHON ® LDPE film -- 87 15 Relationship between stress at 100 % elongation and d-limonene concentration for SELAR @IEVOH film ---- 88 xii - Us T“ Figure Page 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Relationship between tensile strength and d-limonene concentration for ALATHON ® LDPE film ------------- 95 Relationship between tensile strength and d-limonene concentration for SELAR ® EVOH film --------------- 96 Relationship between tensile strength and d-limonene concentration for SELAR ® Co-PET film ------------- 97 Relationship between elongation percent at break and d-limonene concentration in for ALATHON ® LDPE film 105 Relationship between elongation percent at break and d-limonene concentration in for SELAR ® EVOH film - 106 Relationship between elongation percent at break and d-limonene concentration in for SELAR ®ICo-PET film 107 Relationship between heat seal strength and d-limonene concentration for ALATHON ® LDPE and SELAR ® EVOH film ---------------------------------------------- 115 Relationship between heat seal strength and d-limonene concentration for SELAR ® Co-PET film ------------- 116 Change in impact failure weight of the sample films 118 D-limonene standard calibration curve: packed column (G.C. Model #5830) ------------------ 123 D-limonene standard calibration curve: capillary column (G.C. Model #5890) --------------- 125 Relationship of the area responses of d-limonene (G.C. Model #5830 vs. #5890) ---------------------- 126 Neral standard calibration curve: packed column (G.C. Model #5830) ------------------ 128 Geranial standard calibration curve: capillary column (G.C. Model #5890) --------------- 129 D-Limonene concentration as a function of the time 136 Geranial concentration as a function of the time -- 137 xiii INTRODUCTION Aseptic processing and packaging of fruit juices has been reported to give a product of superior flavor and shelf stability, when compared to the same product prepared by traditional canning processes. It provides inexpensive packaging in small sizes, and has virtually created a single service market. Although thermoplastic and paper-based materials can be used in applications previously confined to metal or glass, product compatibility with the packaging system is of major concern in the selection and use of plastics packaging systems for food packaging. Commercially sterile products have been on the market for a considerable period of time. Basically, there are two ways to achieve commercial sterility for both product and package. One is sterilization of the product and package together, using the retort or autoclave procedure, and the other is sterilization of product and package separately, using aseptic technology. Aseptic packages vary from the traditional can and bottle to non-rigid and semi-rigid containers based on thermoplastics, or combinations of thermoplastics with paperboard and metal according to Hersom (1985). For non-rigid and semi-rigid packaging materials, the following packaging systems are being used: (1) pouches or bags; (2) prefabricated cups; (3) form- fill-seal cups made from roll-stock material; (4) plastic bottles; (5) prefabricated, paper-based laminated cartons; and (6) cartons produced from roll—stock material of paper- based laminates (Bernhard, 1986). Because of their relatively low cost and wide acceptance by the consumer, carton-type packages for fruit juice and juice-based beverages have become very popular. Aseptic carton-based packages (with aluminum-foil and plastics layers) account for the largest share of the aseptic package market (Wolpert, 1987). This package form will probably continue to be dominant in the aseptic market. Manufacturers of aseptic, carton systems are listed in Table 1. Containers produced from high barrier co-extruded plastic sheet stock are also finding considerable interest, where they compete favorably against more traditional glass and metal containers. As plastic materials become more widely used for direct contact with food systems, product compatibility with the packaging materials must be considered. The sorption of flavor compounds or "scalping" is one of the most important compatibility problems. Plastics, such as polyolefins, can selectively sorb certain flavor constituents from the product (Foster, 1987). When this occurs, the flavor quality of the product is reduced, and the sorbed flavor components may effect the functional properties of the plastic (Hirose, 1987). It has been reported that the major aroma components in citrus juices are rapidly absorbed into the polymer sealant layer of carton packages (Durr, 1981). Evaluation of the mechanical properties of the sealant polymer layer as a function of sorbent concentration, in addition to measurement of sorbed levels of aroma compounds by the polymer, would make it possible to select the most suitable packaging material for products whose quality is associated with flavor retention. In summary, the major objectives of this study were to: (1) Investigate the absorption of organic volatile compounds in orange juice, namely d-limonene, neral and geranial, by plastic films, which may be used as the contact layer in aseptic package systems. (2) Evaluate the influence of the absorption of these compounds on the mechanical properties of the plastic films, as a function of sorbed concentration. .mmma .Eomuom .uflm oafluoum ca moumuomo .unofia >5 can oumcaEmH oofixouom comouo>n oaumflmuocxm 5H<\uommm\0flummam mcouumo pouoouoiocanomz xmmwsvfiq .uflm oafluoum ca moumuomo oumcaEMH .uflm go: new oofixouom comouoxm sa<\uommm\oflummam mcouumo oouoouolocflnomz ooaoflneoo qu .uflm oafluoum mo unbecoufl>co cm ca moumuoao mumcflema maficome nommm .umon pom ooflxouoa cmmouoam 9H<\uommm\ofiummam co commouoioowiooz HchADmcuoucH .emoum pom oofixoumm comouomn mo ucoacoufi>co cm ca moumuomo oumcflema .umo: pom opflxouom cmmouoam oa¢\nomma\owummam commouoouanoom1b03 xmm mauve vogue: mafiaaflm pom mcflnfiafluoum anemone: snow Housuouuqduzl. .meoummm :ouumo .ofluammm mo muounuommscmz .H manna LITERATURE REVIEW Carton Style Aseptic Packaging Aseptic packaging in laminated paper containers began more than 30 years ago with the development of the Tetra Pak tetrahedron carton. In 1981 the Tetra Brik ®received Food and Drug Administration (FDA) approval, with production in the American marketplace beginning in 1982. In 1983 fruit drinks were launched nationally, though fruit juices did not start filling the pipelines until the second half of the year (Stacy, 1985). By 1984, the number of brands had increased tremendously. The United States sales of aseptics ballooned from 15 million cases to 60 million cases from 1982 through 1984 (Jabbonsky, 1985). Aseptic penetration into the small, single service sizes represented about 100 million gallons, or about 1.3 billion units in 1984 (Cavanagh, 1985). The growth of aseptic flexible packages worldwide has continued on an accelerated pace for more than 20 years (Bergwall, 1984). In 1986, fruit juice volume was at or near an all- time high, registering 1842.8 million gallons in the U.S. Together, fruit juices and fruit drinks accounted for 2708.5 million gallons, which resulted in sales of 9.8 billion dollars. This represents a per annum consumption of 7.7 gallons of fruit juice and 3.5 gallons of fruit drinks by each person in the United States (Stacy, 1987). The total fruit juice volume in the U.S. posted a whopping 38.8 percent growth in gallonage between 1978 and 1986. Orange juice has accounted for more than 60 percent of the total consumption of fruit juice in the U.S. Per annum consumption of fruit juices, by juice types, is shown in Figure 1. Since 1985, single-serve juice packages have proliferated. Three-pack, eight-ounce (250 ml) aseptic "brik" packages, sold about one billion units of fruit drinks in 1986 (Stacy, 1987). This amounts to approximately 190 million gallons of the drinks packed aseptically in 1986. Growth of these aseptic products for the period from 1982 to 1984, is presented graphically in Figure 2. Continuing technological advances in aseptic and sterile packaging will result in cost savings for the manufacturer, and will become a more and more attractive alternative to traditional glass and metal containers for food and drinks requiring refrigeration (Wolpert, 1987). Aseptically packaged juices will become more popular, increasing almost 50 percent during the next 5 years (U.S.Industrial Outlook, 1987). Shelf - Life of Aseptically Packaged Juice Products The shelf life of aseptically packaged juice has been (extensively studied (Mannheim and Havkin, 1981; Potter, 1978 1986 / Orange Others Grape Grapefruit Apple ERIE!- Figure 1. Per annum Consumption of Fruit Juices by Juice Types. ' Source: Stacy, 1987. 42MM Cases 50' 1,000MM UnitsI 40" m ‘ 20MM Cases 3 30- 480MM Units m . +108% Gain 0 a 2°" - 4MM Cases . +400% Gain 10- 96MM Units ~. MM Cases 1982 1983 1984 Year Figure 2. Growth of Aseptic Packages. Source38tacy, 1985. 9 1985). Mannheim and Havkin (1981) compared the quality of an aseptic bottled juice to a hot-filled orange juice. Immediately after filling, the aseptically filled juice was judged to be slightly better. However, sensory differences between the juices diminished rapidly during storage. Potter (1985) reported on the stability of citrus flavors in aseptic packages and found aseptically packed orange juice to be acceptable for up to 8 months at room temperature. DiGeronino (1986) reported that throughout 14 weeks of ambient storage, very little change occurred in the sensory profile (8 flavor notes) of orange juice. However, a very slight increase in cooked and rind notes and a decrease in fresh and sweet notes were observed. Most aseptically packed juices are packaged into laminated carton packages which have a plastic layer as the food contact phase. McLellan et a1. (1987) evaluated an oriented polyethylene terephthalate (OPET) container for use with hot filled apple juice. They concluded that the OPET packaged and quench cooled processed juice was preferred over the glass packaged hot filled juice, for up to 6 months. Although significant losses of aroma components such as d- limonene, neral and geranial from orange juice occurred due to interaction with carton packages, Durr et a1. (1981) concluded that the principal factor contributing to product quality or shelf life was the storage temperature. However, Marshall et al. (1985) reported that sorption of d-limonene by the packaging material reduced the organoleptic quality of 10 citrus juices. Shimoda (1987) found that the absorption of volatile flavor compounds by the inner layer of an aseptic carton material modified the subtle balance of various flavor compounds in the product, which resulted in a change in quality of the flavor. The package environment can significantly affect product storage stability. In order to protect product quality and provide an adequate shelf life, the package must meet a number of requirements including: (1) barrier to light, (2) impermeability to gases and vapors, (3) resistance to absorption of moisture, (4) resistance to flavor or taint interaction with the product, (5) non-toxic materials, (6) unalteration by chemical and/or heat treatment, (7) hermetic scalability, (8) stability for appropriate storage periods, and (9) resistance to handling abuse (Graumlich, 1986). Package Interaction The food industry is becoming increasingly aware of the importance of flavor preservation of products since many foods are highly flavored or spicy, and there is a need to retain these components (Foster, 1987). The oil fraction of citrus juices has a major impact on citrus aroma and flavor. The contribution of volatiles to orange juice flavor has been described by Durr (1981) (Table 2). Because of its lipophilic nature, the oil fraction will absorb into many 11 . Ema Juno :3 30:83 Avannukuouuha uvuahnuonauum§ H355» um 30330143-.. Hansen: .8 Sconce H393: Hgoxonumunoauu H333 H388: mane—cadence 33838: 280515 3:50:33» 33:35 encode .8 H3883 05:8 ounces: unused: Homes 30593» .8 Sodas: 333: 39:32“ .153 Hoaaoaauuou 335005 03333 33893 383130 on noausfiuucoo 88: ~33? 3 coeusowuucou Amv .no>mam oofiofl omomuo ou moaapmHo> no coauonaupooo one .N manna 12 packaging polymers. Thus, the juice develops a flat taste which is perceived as a loss in fresh-like quality (Marshall, 1985). Durr (1981) reported that the decrease in limonene concentration, due to absorption into the polyethylene lining of the carton packages, was 40 percent of the total quantity in the orange juice within 6 days after filling. The rate of sorption of d-limonene by the lining material was then reduced. The control, which was bottled juice, showed a 10 percent loss of d-limonene concentration after 90 days of storage. Durr (1981) concluded that the distinct and rapid loss of limonene into the polyethylene lining of the soft package could be considered as an advantage, as less precursor of a-terpineol and related off-flavor components were available. Marshall (1985) reported that better than 60 percent of the d-limonene in the orange juice was absorbed by low density polyethylene, while only 45 percent was absorbed by Surlyn at The loss of d-limonene into the sealant layer was directly related to the thickness of the sealant layers (polyethylene, polypropylene and/or ethylene vinyl acetate) and not the oxygen permeability of the film. The presence of d-limonene resulted in swelling of the polymer, which apparently had detrimental effects beyond that of reducing its concentration in the juice and of producing localized stress in the polymer. Absorption of d-limonene could also reSHJIt in the absorption of other compounds into the polymer. I i” 0V. 6"! th .- FAQ UV. 521 t): ‘ I! k... u a.” on. .A ”F .55 A 8" -. «Ii ‘A 5n, 13 Hirose (1987) reported that low density polyethylene and ionomer films rapidly absorbed d-limonene from orange juice within 3 days storage. The rate of absorption then slowed down and reached equilibrium after 12 and 6 days respectively at 24°C, 49 percent R.H. He concluded that Surlyn ® (zinc type) would be better than low density polyethylene as a contact layer for orange juice, with respect to d-limonene sorption. Ikegami et al. (1987) reported that a higher level of sorption of volatile compounds in a fruit flavored solution was observed with polypropylene (PP) as the contact layer of a laminate pouch structure (PET/aluminum foil/PP) than with a high density polyethylene (HDPE) film as the contact phase of the pouch laminate (PET/aluminum foil/HDPE). The authors reported the distribution ratios (content in films/solution) of the volatile compounds were influenced by the molecular structures of the compounds, and the distribution ratio was closely correlated to the density of the film. For sorption by polyethylene, the partition or distribution ratio was found to be inversely proportional to the polymer density. Equilibrium partition coefficients (Ke) for sorption of aroma compounds by plastics packaging materials in an aqueous syStem were calculated by Kwapong and Hotchkiss (1987). Ke = [Cpleq / [Caqleq (1) where [Caneq is the equilibrium concentration of aroma cxmmpound in the aqueous phase and [Cp]eq is the equilibrium 14 was obtained from the following expression for a difference method: [Cp]eq (wt/wt) = ([Caq11n1tia1-[Caq]eq) * vol.aq.phase / wt polymer (2) A Ke for limonene indicated a strong affinity for the plastic phases. The authors also indicated that sorption by low density polyethylene (LDPE) and two grade of ionomer was mainly an absorptive process. Hotchkiss (1987) reported that sorption of volatile flavor compounds raised the possibility that an important attribute (flavor) could be adversely influenced by contact with some polymeric packaging materials. The extent of sorption depended on several factors including type of polymer, the concentration and chemical structure of the aroma compound, the storage temperature and time, the mass of polymer and the presence of other components in the aqueous phase. The equilibrium sorption of d-limonene by high density polyethylene (HDPE)/sealant laminate and a wax/polyvinyl alcohol (PVOH)/glassine/PVOH/wax structure was studied by Mbhney et al. (1988), as a function of limonene vapor concentration. The solubility of d—limonene in the glassine base structure was found to be substantially lower than in the HDPE structure, at the same limonene vapor concentration anCi‘temperature. .A solubility coefficient can be calculated 15 from sorption experiments using the following expression. M... cob (3) where S : solubility coefficient. ”La total amount (mass) of vapor absorbed by the polymer at equilibrium for a given temperature. (D : weight of the polymer sample. b : penetrant driving force in units of concentration. This expression can be applied to organic vapors exhibiting non-ideal diffusion, as well as non-interacting penetrants (Hernandez et al., 1986). Permeation and sorption studies were performed on a high impact polystyrene (HIPS) package containing onion/garlic flavored sour cream (Toebe, 1988). Sorption studies were also carried out on high density polyethylene (HDPE) and polypropylene (PP). The solubility of probe compounds, namely dimethyl disulfide and dipropyl disulfide, was substantially higher in HIPS than in HDPE or PP. AnalyticalIMethods of Flavor Analysis (Limonene) D-limonene content of orange juice can be determined using the bromate method of Scott et a1. (1966), which combines distillation with a bromide-bromate titration. The Imathod is based on the quantitative combination, in acid solution, of d-limonene with bromine. In this technique, f) C) we [‘1‘ I“ 16 orange oil is distilled from a small sample of juice mixed with a completely miscible, volatile solvent. The distillate is acidified and titrated with standard bromate solution. In acid solution, the bromate releases bromine which reacts quantitatively with d-limonene through saturation of the double bonds. At the end point, excess bromine completely destroys the color of methyl orange. Hirose (1987) extracted and analyzed for d-limonene levels in plastic films in contact with orange juice, using the bromate method of Scott et al (1966). Schreier (1981) extracted fresh juice with an organic solvent to obtain a flavor extract suitable for analysis by capillary gas chromatography (G.C.) A technique which permits accurate quantitative analysis of some of the most volatile flavor components in fresh orange juice has been developed by Moshonas (1986, 1987). In this procedure, distillate from fresh orange juice is analyzed by direct injection into a capillary gas chromatographic column connected to a flame ionization detector (FID) system. The FID responds to virtually all organic compounds. The Electrobalance Sorption / Desorption Apparatus (Cahn Instruments Inc., Cerritos, CA) has also been used in sorption studies of volatile flavor components (Mohney, 1988). This method can be used to accurately measure flavor sorption by plastic materials which have been surrounded with .a constant concentration of organic vapor. A limitation is that it can analyze only one component or total components at 17 a time. A dynamic headspace analysis technique has recently been developed which significantly enhances recovery of volatiles. The Tekmar Model 4000 concentrator system (Tekmar Co., Cincinnati, OH) interfaced to a gas chromatograph with flame ionization detection, is designed for this application. Detection limits of low part-per billion levels are obtainable with good reproducibility (Toebe, 1988). The volatile components in orange essence have been described by Moshinas and Shaw (1984). Effect of water Sorption on Mechanical and Physical Properties In general, the mechanical and physical properties of plastic materials are affected by environmental factors, including temperature and relative humidity. For example, the tensile properties of thermo-plastics are temperature dependent. In addition, the mechanical properties of hydrophilic polymers such as a polyamide are influenced by the relative humidity of test, as a result of moisture -sorption. In this case, moisture may act as a plasticizer (Rodriguez, 1982). The relationship between modulus of elasticity and temperature, as a function of moisture content, for Nylon 6 is presented graphically in Figure 3, While the relationship between yield stress and temperature as a.function of moisture content for Nylon 66 is presented in Figure 4 (Toray Co., 1983). 18 ethylene vinyl alcohol copolymer (EVOH), exhibit dramatic changes in oxygen permeability depending on the quantity of water vapor present (Foster, 1987) (Figure 5). A method to 'measure oxygen transmission rates of EVOH at precise relative humidities has been described by Demorest (1987). The effect of relative humidity on the diffusion of toluene vapor through a multi-layer coextrusion film structure containing moisture sensitive hydrophilic barrier layers (i.e. nylon and EVOH) was reported by Liu et al. (1988). Water vapor was found to exhibit strong interactive effects with the moisture sensitive polymer layers of the laminate, which resulted in an increase in the diffusion of toluene vapor through the barrier structure. Effect of Organic vapor Sorption on Mechanical and Physical Properties Hirose (1987) reported that the absorption of d-limonene by polymers generally affected the (a) modulus of elasticity, (b) tensile strength, (c) percent elongation, (d) seal strength and (e) impact resistance of the polymer. 19 a: 5 < E 8 . o~ 4 .x '2‘ o 3" H .3 v 2. m ----0% Moisture .3 1 - .__. Equilibrium at 3 _, environment 5 0 I ‘?"—r- l ——— Equilibrium in W -30 -1o 10 30 50 7o 90 110 water Temperature (°C) Figure 3. Relationship between modulus of elasticity and temperature as a function of a moisture on Nylon 6. 1000 A. 800 ' N < 5 .\ 600 ' ow 5 400 ' 3 g . . ‘_ 0% >.' 200- — 2.5% 0 I I I I I I —- 8°5% -50 -25 0 25 50 '75 100 125 Temperature (°C) Figure 4. Relationship between yield stress and temperature as a function of moisture sorbed by Nylon 66. 20 10 Selar PA 1O Copolyester Barex 210 10 PVDC (XU-32024) Oxygen TR (cc. mil/100 in“2 /24 hrs) -3 1° 32% EVOH 27% EVOH 10' J I I I 0 20 40 60 80 100 Relative Humidity Figure 5. Oxygen Barrier Properties of various plastic films. Foster, 1987. MATERIALS.AND METHODS (a) Orange Juice The orange juice used in this study was 100 percent pure orange juice obtained from the Orchard Grove Company, East Lansing, MI. (b) Plastic films I Three plastic films were evaluated in this study, namely ALATHON ® 1645 (low density polyethylene, ALATHON ® LDPE) , SELAR ® E-44762-16-1 (ethylene vinyl alcohol copolymer, SELAR ® EVOH) and SELAR ® #24328 (co-polyester, SELAR ® Co-PET) . The thickness of these films were 1.65 mil (41.9 um), 0.83 mil (21.1 um) and 2.65 mil (67.3 um) respectively. The test films were provided by the DuPont Company (Wilmington, DE). (c) Probe compounds D-limonene was obtained from the Aldrich Chemical Company, Inc. (Milwaukee, WI), and neral and geranial were obtained from the K & F Corporation, BASF Group (New York, NY). 21 22 EXPERIMENTAL METHODS Quantitative Analysis of'Aroma Compounds Two analytical methods were used to determine the concentration of aroma compounds, namely, the bromide-bromate titration and a gas chromatographic (GC) technique. D- limonene, neral and geranial were selected for probe compounds in this study because of their contribution to orange juice aroma and ease of detection. I] E 'l “E I 1'! l' D-limonene concentration levels were determined by the bromide—bromate titration (Scott and Veldhuis, 1966) method. Results from the titrimetric method were compared with results from the gas chromatographic analysis. The reagents used were: (a) Standard solution of Potassium Bromide-Bromate (Moore, 1965) The solution is made by dissolving 2.8 g KBrO3 and 12 g KBr (Aldrich Chemical Company, Inc.) in boiled water and diluting to 1 1 with boiled water to obtain a 0.099 Normality (N) solution. The solution is then diluted to 0.0247 N solution with distilled water (1 part solution + 3 parts water). One ml of 0.0247 N bromate supplies bromine to react with 0.00084 g of d-limonene (Scott and Veldhuis, 1966). 23 (b) Iso-propanol (Fisher Scientific Company, Fair Lawn, NJ) (c) Hydrochloric acid (MALLINCKRODT, Inc., Paris, KY) The concentrated acid is diluted to 33 percent prior to use. (d) Methyl orange indicator (Fisher Scientific Company) 0.1 percent (w/v) in water. LEW Packed column and capillary column gas chromatographic techniques were used for determination of the probe compound concentrations in the juice and films. The gas chromatographic technique, using the capillary column, was effective in determining the concentration levels of neral and geranial in juice and films. Standard calibration curves of response vs concentration were constructed for each probe compound, for both gas chromatographic techniques, from standard solutions of known concentration. Standard solutions were prepared by dissolution of known quantities of d-limonene, neral and geranial in ethyl acetate (Aldrich Chemical Company, Inc.), respectively. The concentration of the probe compounds in each study was determined by reference to the calibration curves (APPENDIX D. Two Hewlett Packard (Avondale, PA) gas chromatographs, equipped with dual flame ionization detection (FID), were used for these analyses. Model #5830A was equipped with a packed column and Model #5890A was equipped with the capillary column. The GC conditions were as follows: 24 MQdfil.i§filQA Column: 1.83 m; 3.175 mm O.D.; stainless steel packed with 5 % SP 2100 on 100/120 mesh Supelcoport (Supelco, Inc., Bellefonte, PA); Carrier gas: Helium at 30 ml/min.; Temperature: Oven temperature - 150 °C; Injector temperature - 175 °C; Detector temperature — 350 °C; to give a retention time of 1.17 minutes for limonene. Model_§fl&QA - splitless injection port Column: 60 meter; 0.25 mm I.D.; Fused silica capillary; Polar bonded stationary phase; Supelcowax 10 (Supelco, Inc., Bellefonte, PA); Carrier gas: Helium at 30 ml/min.; Temperature: Injector temperature - 200 °C; Detector temperature — 250 °C; Initial oven temperature - 75 °C; 25 Initial time - 8.0 min.; Temperature program rate - 4.0 °C/min.; Final temperature - 200 °C; Final time - 4.0 min; to give retention times of 13.76 minutes for limonene, 32.13 minutes for neral and 33.73 minutes for geranial. Recovery of Aroma Compounds 20 pl d—limonene, 1.0 ul neral and 1.0 ul geranial were dissolved in 100 ml iso-propanol, to give 168 ppm (w/v) d- limonene, 4.4 ppm (w/v) neral and 4.4 ppm (w/v) geranial. Twenty five ml of each solution were placed into a distillation flask containing several glass beads, and 25 ml distilled water added using a 10 ml PYREX ® disposable pipet. The distillation flask was connected to an adapter equipped with an inclined plate as a trap. The other end of the tube adapter was connected to a Graham condenser. The sample was distilled into a 150 ml beaker using an electric heater, at the maximum temperature setting. Completion of distillation was apparent by observation of: (a) The syrupy consistency of the juice due to concentration; (b) condensation of water in the connecting tube; and (c) collection of 30 ml or more distillate. The bromide-bromate titration and the gas chromatographic analyses, were performed in order to compare the percent recoveries for the two analytical methods. 26 For the titration method, the amount of d—limonene was determined using the following equation. (ml titer - ml blank) x 0.00084 = d-limonene content (g/25 ml) (4) For the gas chromatographic analyses, all injections were direct on the column at a constant volume of 1.0 ul using a 10 [ll syringe (MICROLITER ® #701, HAMILTON Company, Reno, NV), after measuring the volume of the collected distillates. The concentrations of the probe compounds were determined using the calibration curves previously described. Percent recoveries of the probes were calculated based on the concentrations before and after distillation. Determination of d-limonene in Orange Juice To determine the d-limonene concentration in the juice product, the juice was first distilled, according to the procedure previously described (Scott and veldhuis, 1966). For GC analysis, all injections were direct on the column at a constant volume of 1.0ul. Concentration of d-limonene was determined using a calibration curve. Storage Stability of Orange Juice Antioxidants (SUSTAIN W, SUSTAIN 20A , UOP Process Division, McCook, IL) and an antibacterial agent (Sodium azide, Aldrich Chemical Company, Inc.) were added to the 27 orange juice in order to prevent changes in the limonene concentration in the juice as a result of oxidation and to inhibit microbial growth during storage. Each of 0.02 percent (wt.of the preservatives/wt.of the juice) SUSTSAIN W, SUSTAIN 20A and sodium azide were added to the juice at the beginning of storage. The components of the preservative blend are shown in APPENDIX H. The quality of the orange juice was examined using the following indicators: (a) Quantitative analysis of d-limonene in the juice The concentration of d-limonene in the juice was determined using the gas chromatographic (packed column) technique following distillation of the juice. Juice was stored for 17 days at room temperature (21~22°C) and in a refrigerator (4~6°C). (b) Microbial Growth (LACTOBACILLUS CELLOBIOSUS) The preservatives were added to the juice, and after one day storage a 250 m1 sample was removed and inoculated with a 10 ml aliquot of cell culture (107 cells/ml cell culture). The solution was then stored at room temperature (25°C). At predetermined time intervals a 0.1 ml sample was removed and placed on an agar-plate. The plate was incubated at 37°C for 48 hours, and the colonies counted and reported as the cell number per 0.1 ml of the juice. Sampling was continued every 10 days for 30 days. The reagents used in this study are summarized in Table 3. 28 AH: .mcamcmq ummm .mcmmEoo m>ouu oumzouo. woman omcmuo mesa w OOH loHQEmu man no l>\zc r No.os l.oo HmoHEono roauosac moHNavonoom A.OCH mODv dom ZH«bom mom munch vN you noomnaofi 9.2 no umofln 583 mm: 35 mooaoo mamcem Eoum msmficmmmnoouofle commasoocH mDmOHmoaqmo mDAAHudmOBudq mHmEmm wo>aum>ummmum mumHQ “mud musuaso Haoo Emficmmmuoouofiz .mosbm nbzoum Hmflnonoas on» CH pom: uncommom .m wanna 29 Extraction Method of Aroma Compounds from Plastic Films Preliminary studies were carried out using high density polyethylene (HDPE) films, to develop the analytical procedure for quantifying the levels of sorbed limonene, prior to initiating the actual immersion studies. The purpose of this study was to determine a correlation between the different analytical methods for the probe compounds determination. Variables considered included the solvents used for extraction, the G C techniques (packed and capillary column analysis) and the two analytical methods, namely, the titration method and the gas chromatographic procedure. Two sheets of 2 mil (50.8 gm), 5" x 4" (12.7 cm x 10.16 cm) HDPE film (Crown Zellerbach, Greensburg, IN) (258.1 cmz) were placed in brown glass bottles containing 260 ml of the orange juice, and stored for 10 days at room temperature. Following immersion, the films were removed from the bottles, rinsed with distilled water for one minute, and then cut up into pieces 1 cm x 1 cm. The film pieces were then placed into 30 ml septum seal vials with 25 ml of solvent and vials sealed with silicone coated septa and tear away seals (Supelco, Inc., Bellefonte, PA). One sheet of the film was immersed into iso-propanol and the other one into ethyl acetate in order to compare extraction of the aroma compounds. After extraction for 24 30 hours, 1.0 ul was injected directly into the gas chromatographs. The results were compared with the iso- propanol extraction technique, using the distillation process as described by Hirose (1987). The concentrations of the probe compounds were determined from the respective calibration curves. Immersion Study - mechanical Properties WW Two sheets, 5" x 4" (258.1 cm2), of each test film, ALATHON ® LDPE (ALATHON ® 1645), SELAR ® EVOH (SELAR ® E- 44762-16-1) and SELAR ® Co-PET (SELAR ® #24328), were placed in brown glass bottles containing 260 ml of the orange juice and stored in the dark at 21°C. The volume to area ratio of the juice and the films were kept constant at 1.01 (m1/cm2). The films were removed from the bottles at predetermined times of 1, 3, 6, 14 and 24 days, rinsed with distilled water for one minute and then cut into 1 cm x 1 cm pieces. The weight of each sample film is shown in Table 4. Twenty five ml of orange juice was removed from each bottle in order to determine the amount of d-limonene remaining in the juice. The concentration of d-limonene in the juice was determined by the G.C., packed column method. The cut up sample film was placed into septa seal vials containing 25 ml ethyl acetate and the vial sealed with Table 4. The weight 31 of sample films.(a) Films Wt.per Film Sheet 5" x 4"(b) (258.1cm“2) (9) s.d. ALATHON ® LDPE 0.56 :t 0.01 SELAR ® EVOH 0.30 :t 0.02 SELAR ® Co-PET 1.00 :l: 0.04 (a) Average of 20 measurements. (b) 1.12 g of ALATHON ® LDPE film, 0.60 g of SELAR ® EVOH film and 2.00 g of SELAR ® Co- PET film were immersed in each bottle. 32 silicone coated septa and tear away seals. After 24 hours, 1.0 01 of the solution was removed and injected directly into the gas chromatographs for quantification. Gas chromatographic analysis was carried out on both packed and capillary columns. The concentrations of the probe compounds were determined from the respective calibration curves. 1! l i J E l' E E] Ii E'J Films which had been immersed in the juice for a predetermined number of days were removed from the bottles and rinsed with water for one minute. The sample films used for seal strength measurement were sealed using an impulse heat sealer (Sentinel Heat Sealer Model #16TP, Packaging Industries, Inc., Hyannis, MA), and then immersed in the juice. The following mechanical properties were determined for the film samples: Stress - Strain Properties (a) Modulus of Elasticity (b) Yield Stress (c) Stress at 100 percent Elongation (d) Elongation percent at Break (e) Tensile Strength (f) Seal Strength The respective mechanical properties were determined for each film, as a function of absorbent concentration, using an 33 Universal Testing Instrument (Instron Corporation, Canton, MA). ASTM Standard method D 882-83 (1984) was adopted for all stress-strain procedures. Ten specimens were tested to obtain each sample point; however, for the modulus of elasticity, six specimens were tested to obtain a sample point. The mechanical properties of the control films (not immersed in the juice) and the sample films (immersed in the juice and containing different absorbent concentration levels) were measured. The film sample sizes and film/juice surface area to volume ratios are presented in Table 5. The juice volume to film area ratio ranged from 1.01 to 1.06 (ml/cmz). The heat sealing conditions used for the films are shown in Table 6 and test conditions for stress - strain analysis are presented in Table 7. Impact Resistance Sample specimens of the ALATHON ® LDPE, SELAR ® EVOH and SELAR ® Co-PET were immersed into orange juice until equilibrium (limonene concentration in the films) was established. A free - fall dart method (ASTM standard D 1709-85, 1986) was performed to compare the impact resistance of the films, initially and at equilibrium. A drop height of 0.33 m instead of the standard 0.66 m was used in these tests. The impact resistance of the control films (not immersed) and the sample films (immersed in the juice for 24 days) was measured. The staircase testing technique (ASTM D 1709-85) was used 34 to determine the impact resistance of the sample films. The impact failure weight Wf (g) was calculated using the following equation. Wf = W0 + [ AW * (A / N - 1 / 2 ) ] (5) where: Wf = impact failure weight,g, W0 = the missile weight to which an i value of zero is assigned,g, AW = uniform weight increment used,g, A = i x ni, and 10 (the total number of failures). where i: integers 0, 1, 2, etc. ni: number of failures in each missile weight. 35 .nbmcouum down use: can numcouum mafimcou .xmmnb um ucoouom cofibmmcoao .c0aummcoHo unwound ooa um mmmuum .nmouum name» mcacsaoca .mmauuomoua cflmubml mmouum Any .mofisfl mocmuo on» no mssHo> Amy AEom.mH x Eom.>H. mo.H onma m.HmnH m rm.m x an oocmumfimom boomeH AEO>.NH x Eom.oav Ho.H owm H.mm~ N am x rv ADV cflmuum I mmouum AEom.mH x Eom.mHv mo.H osma m.HmnH h :m.m x rm mufioaummam mo msasooz l~.eo\sel lag. l~.2ol mafia ocean Edam muomnm boogm auuomoum Hmowcmsomz no no mo mou¢\.ao> AmeEsao> mend umnEsz .mowumu oEoHo> ocean ou \ mono Edam can omen onEmm Edam .m manna 36 Table 6. Film heat sealing conditions. Sample ALATHON® SELAR® SELAR® LDPE EVOH Co- PET Impulse Time 0.4 0.5 0.6 (seconds) Cooling Time 2.5 2.0 2.0 (seconds) Jaw Pressure (psi) 22 30 30 (kg/cmAZ) (1.55) (2.11) (2.11) 37 Table 7. Test conditions for film stress - strain evaluation. Sample ALATHON®/ SELAR® SELAR® LDPE EVOH Co- PET (a) Modulus (b) (a) Modulus (b) Tensile of El. Tensile of E1. TeSt °°nd1t1°n5 MD*/CD** MD / CD MD CD MD / CD Cross Head Speed 20 1.0 0.5 1.0 1.0 (in/min.) (cm/min.) 50.8 2.54 1.27 2.54 2.54 Chart Speed(in/min.) 20 10 10 20 10 (cm/min.) 50.8 25.4 25.4 50.8 25.4 Full Scale (lbs) 5 5 20/50 20/50 (kg) 2.27 2.27 9.07/22.7 9.07/22.7 Grip Separation (in) 2 4 2 4 (cm) 5.1 10.2 5.1 10.2 (a) Test conditions of yield stress, stress at 100 percent elongation, elongation percent at break and tensile strength. (b) Test conditions of modulus of elasticity. * Machine Directions (MD) ** Cross Head Directions (CD) Note: Test condition of seal strength of all film samples was same as (a) of ALATHON® LDPE/SELAR® EVOH film samples. RESULTS AND DISCUSSION Recovery of Aroma Compounds by Distillation The percent recovery of d-limonene was determined using three analytical methods: namely, distillation followed by gas chromatographic analysis on both packed and capillary columns, and by a titrimetric procedure. Recovery of neral and geranial was determined by a gas chromatographic procedure, employing the Hewlett Packard Model #5890 gas chromatograph, equipped with a capillary column. The level of recovery of each aroma compound was determined from standard solutions of known concentration. The percent recovery of d-limonene using the respective analytical techniques is summarized in Table 8. As shown, the average percent recovery of d-limonene for the replicate runs by the distillation procedure was 99 i 4 %, using packed column analysis, 104 i 11 %, using capillary column analysis, and 96 i 3 % by the titration method, respectively. Recoveries of neral and geranial from standard solutions, were determined using the distillation procedure, followed by capillary column analysis, and are presented in Table 9. As shown, the average percent recoveries of neral and geranial, using the distillation technique followed by capillary column analysis, were 90 i 15 % and 89 i 16 %, respectively. 38 39 Table 8. Percent recovery of d-limonene from standard d-limonene solutions using the distillation technique. Concentration of d-limonene Packed Column Capillary Column Analysis Analysis(a) Analysis(b) Titration (ppm) * (mg/25ml) (ppm) * (mg/25ml) (mg/25ml) Run 1 Before 121.0 3.026 114.0 2.850 3.180 distill. After 114.8 2.870 135.7 3.939 3.012 distill. 116.0 2.899 122.5 3.062 3.020 127.9 3.197 124.2 3.105 3.255 Average 119.6 2.989 127.5 3.187 3.096 % Recovery 98.8 98.8 111.8 111.8 97.4 Run 2 Before 117.4 2.934 114.4 2.860 3.232 distill. After 120.9 3.022 102.4 2.560 3.171 distill. 114.8 2.870 100.8 2.520 3.138 112.7 2.819 109.3 2.733 3.163 Average 116.1 2.904 104.2 2.604 3.157 % Recovery 98.9 99.0 91.1 91.0 97.7 G.Average 98.9 % 103.5 % 95.5 % s.d. 14.4 % 110.9 % 12.8 % (a) H.P.#5830 G.C.equipped with packed column. (b) H.P.#5890 G.C.equipped with capillary column. * PPm (Wt/v) 40 Table 9. Percent recovery of neral and geranial from standard solutions using the distillation technique. Concentration of Aroma Compounds Neral Geranial (Ppmrwt/v) (ppm,wt/v) Before 3.81 4.82 distill. After 2.79 3.40 distill. 3.89 4.77 3.66 4.68 Average 3.45 4.28 % Recovery 90.6% 88.8% s.d. 115.3% i15.9% 41 Storage Stability of Orange Juice The results of the storage stability studies for the orange juice product are summarized in Tables 10 and 11. The stability of orange juice stored at room temperature and in the refrigerator was determined by the quantitative analysis of d-limonene, and by measurement of microbial growth (total counts) in the orange juice containing antioxidants and antimicrobial agent. .As shown, the addition of preservatives to the juice prevented deterioration of product quality. Loss of limonene was minimal at both temperatures of storage after 17 days (Table 10). Further, there was no evidence of bacterial growth detected after 30 days of storage at 25%: (Table 11). Addition of the antioxidants and antibacterial agent minimized oxidative loss of limonene in the juice and inhibited microbial growth during storage for 17 days, even at room temperature. Extraction of Aroma Compounds from Plastic Films The amount of d-limonene and geranial sorbed by high density polyethylene (HDPE) film, before and after distillation is presented in Tables 12 and 13, respectively. It was possible to detect d-limonene and geranial using the gas chromatograph equipped with the capillary column. Neral, 42 Table 10. D-limonene concentration in the orange juice containing antioxidant and antimicrobial agents. Storage d-limonene Conc. (mg/25ml) Time (days) 49C 219C. 0 3.319(a) 3.319(8) 17 3.244 3.166 3.247 3.365 3.146 3.206 Average 3.212(b) 3.246(b) Recovery(c) 96.8% 97.8% (c) = ((b)/(a)) x 100 Table 11. Microbial stability of orange juice containing antimicrobial agent, stored at 25°CL Storage Number of cells/0.1 ml juice Time (days) Sample A Sample B 1 No GROWTH No GROWTH 10 No GROWTH No GROWTH 20 No GROWTH No GROWTH 30 No GROWTH No GROWTH 43 Table 12. Measurement of d—limonene and geranial sorbed by HDPE and extracted using different solvents. Bottle Film Solv. Capillary Column Packed Column No. Sample Analysis (a) Analysis (b) No. (mg/gHDPE) (mg/gHDPE) limonene Geranial limonene 1 1 IPA! 3.0850 0.0096 2.8117 2 EA** 2.7664 0.0060 2.6470 2 3 IPA. 3.0420 0.0076 3.0113 4 EA 3.7589 0.0081 3.2802 3 5 IPA. 3.4765 0.0081 3.3711 6 EA 3.3704 0.0076 3.1748 4 7 IPA. 3.8297 0.0049 4.3144 8 EA 3.2179 0.0060 3.0351 5 9 IPA. 4.4548 0.0054 4.8096 10 EA 3.9268 0.0082 3.4989 IAverage I IPA I 3.5776 0.0071 I 3.6636 I s.d. i0.5858 i0.002 i 0.8622 IAverage I EA I 3.4081 0.0072 I 3.1272 I s.d. $0.458? 10.0011 1 0.3174 (a) * ** EA H.P.#5890 G C (b) H.P.#5830 G C IPA = iso-propanol = ethyl acetate equipped with capillary column. equipped with packed column. 44 Table 13. The amount of d-limonene in the HDPE extracted using IPA.with distillation. (a) H.P.#5830 G.C equipped with packed column EflJnl Solv. limonene (mngHDPE) % Recovery Sample Packed column Titration (b) (c) No. Analysis(a) 1 IPA. 3.3007 3.6806 85.2 89.7 3 IPA. 3.0462 2.5560 98.9 119.2 5 IPA. 3.1593 3.0189 106.7 104.7 7 IPA. 4.2852 4.8744 100.7 87.9 9 IPA 4.7420 5.1246 101.4 92.5 98.6 98.8 (b) The ratio of before / after distillation (c) The ratio of G C #5830 / Titration 45 however, could not be detected. There was no significant difference in the results from distillation using one of two different solvents, namely iso- propanol (IPA) and ethyl acetate (EA). The correlation coefficient between the results was 0.962 (APPENDIXIH). There was no significant difference between results obtained from the two different gas chromatographs, one of which was equipped with a packed column and the other with a capillary column. The correlation coefficient between these two chromatographic analyses was 0.904. The amount of d-limonene sorbed by the HDPE film was compared, before and after the distillation process. Limonene levels were determined by gas chromatographic analysis on the packed column and the results compared to those obtained by the titration method. The ratio of the results obtained before and after distillation was 99 percent. The correlation coefficient between these methods was 0.954. Concentration of d-limonene obtained by the different analytical methods is summarized in Table 14. The average percent recovery by the titration method and by gas chromatographic analysis, was 96 percent. The correlation coefficient between these methods was 0.951. 46 Table 14. Limonene concentration in the films measured using different analytical methods. limonene (mg[gHDPE) Packed Column Titration (b) Analysis (a) 2.870 3.012 95.3 2.899 3.020 96.0 3.197 3.255 98.2 3.022 3.171 93.5 2.870 3.138 91.5 2.819 3.163 89.1 3.046 2.556 119.2 3.159 3.019 104.7 4.285 4.874 87.9 4.742 5.125 92.5 Average 97.0 s.d. 9.0 (a) H.P.#5830 G.C equipped with packed column. (b) The ratio of G C #5830 / Titration. 47 Immersion Studies Sorption Measurements Measurement of the aroma compounds in the orange juice and test films was determined as a function of storage time. I I I I I 0 II o - IlII‘I‘ 0‘ “I ‘ al.. .0 - n D-limonene concentration in the orange juice and in the juice following contact with the plastic test films; namely, ALATHON ® LDPE (ALATHON ® 1645), SELAR ® EVOH (SELAR ‘9 E- 44762-16-1), and SELAR ® Co- PET (SELAR ® #24328), were determined as a function of storage time. The concentration levels of d-limonene in the respective juice samples are summarized in Tables 15 and 16. For better illustration, limonene concentration in the orange juice, as a function of storage time for the control and the ALATHON ®LDPE and SELAR ® EVOH film samples, are presented graphically in Figure 6. The initial d-limonene concentration in the control juice was 45.83 mg/260ml orange juice, and the final concentration was 43.34 mg/260m1 orange juice. This represented a decrease in d-limonene concentration of approximately 5.4 percent over a storage period of 24 days, at 21°C. However, as shown in Table 17, there was no statistically significant difference between the d-limonene levels in the control juice over the total storage time, at the 99 percent confidence interval. 48 can you mcofibowncfi 030 can moon boonomwfio does» no ommuw>< Anv can nod mcofibooncfi 03b ocm moon ucoumMMHo 03» co oomph mum mama Amy vm.m vn.mv mn.H mm.nm No.0 oo.m~ o¢.m wm.me gm mm.o om.gv mm.~ mm.mv mv.o mm.>m H¢.H mm.vg vH mm.H oa.mv mn.H Ho.mv mv.m hm.m~ v>.m vm.vv m am.o mm.Hv nm.~ Hm.mm mm.H mm.n~ mo.~ Nv.mv m mv.~ vm.~v on.H mv.Hg mN.~ mm.vm on.o HH.mv H mm.v. Anvmm.mv mm.v Anvmm.mv mm.v Anvmm.mv mm.v Abvmm.mv o o.m H x .o.w H x .o.m H x” .o.m H x smouoo organ ro>m omfimm mung @zomsfig Sourcoos 2933 sue: mofisb sums ocean Suez moasb ocean mmcmuo mafia momuoum ~AEom~\oEV coflumnbcmocoo mcmcoefla Amy .manm bomb has; bomucoo mcwzoaaom .OoHN um mmmnobw mafiuso oofisfl mocmuo as oofibmubcmoaoo mcwcoEHano a“ mmcmno .ma magma 49 u mEHu mo ooHqu m um>o mOHDn mocmuo map CH mchHmEmu ococoEHHno mo bcmouom m>HDMHmu u 0328\ro u 83o r. A>\b3.emdv b u mEHb um moHsn may cH mcmcoEHHuo mo coHumuucoocoo no « oonm may CH ocmcoEHHno mo .ocoo HmeHcH u oo Amy mm.ooH nn.m>H Hm.Hm mo.wvH -.om Nm.h0H nm.gm me.mmHfl «N mH.mm Hm.N>H mH.vm mm.mmH mm.mm mN.GOH mm.mm mb.onH vH vm.mm Hm.>>H mH.om mm.HmH mm.nm m>.m0H mn.mm vm.onH w mm.mm mH.omH 34m Hm.omH oném mH.mOH mH.HOH vmdnH m nm.om mm.~mH mm.mm mv.mmH mm;ws. mv.va nm.¢OH vo.mmH H oo.OOH nm.mnH oo.oOH nm.m>H oo.ooH n~.m>H oo.o0H nm.m>H o oo\bo Hence oo\bo AEQQH oo\bo Heads oo\uo««_eeaav Hm>mo no 00 no Amy «Do Bum—loo @mmqmm mo>m @mdqmm MEGA Ozone; AHouucoov 05:. 2.33 00.25 anz moHso 20H: moHsb moHso omcmuo mammobw .meHHm bomb an3 uomucoo mcHsoHHom .owHN um oomuobm mcHuso moHsn may CH mchHmEmu mcocoEHHuo no ucooumm m>HumHom .mH OHQMB 50 120 111: 100 T T 80 I (=4 Isl Remaining in Juice 1 Juice ’ I W/SELAR® - EVOH I W/ALATHON® - LDPE Relative % of d-Limonene (Ct/Co*100) 404 I I I I I II 0 3 6 9 12 15 18 21 24 27 Storage Time (days) Figure 6. D-limonene concentration in the orange juice as a function of storage time for different films. 51 * Significant at 99 % Table 17. ANOVA table for d-limonene concentration in the control juice sample. Sourse Sum of_Squares d.f. Mean Square F - test TR 33.322 5 6.664 0.644 E 207.035 20 10.352 Total 240.358 25 Storage Mean Count Std. Dev. Std. Error Time(days) 0 45.830 6 4.686 1.913 1 48.112 4 0.706 0.353 3 46.415 4 2.092 1.046 6 44.338 4 1.414 0.707 14 46.165 4 3.746 1.873 24 45.070 4 3.392 1.696 Comparison Mean Difference F-test 0 vs. 1 -2.282 0 vs. 3 -0.585 0 vs. 6 1.493 0 v5.14 -0.335 0 v3.24 0.760 1 vs. 3 1.697 1 vs. 6 3.775 1 v3.14 1.947 1 v3.24 3.042 3 vs. 6 2.077 3 v5.14 0.250 3 v3.24 1.345 6 v3.14 —1.827 6 v3.24 -0.732 14 vs.24 1.095 52 The limonene concentration in the control sample was assumed, therefore, to be constant over the time of storage and the variation in limonene levels obtained was considered to be within the range of experimental error. As shown in Figure 6, the d-limonene concentrations in the juice containing the ALATHON ® LDPE film strips decreased immediately and attained a constant level of 27.50 mg/260ml orange juice (or a 41 percent decrease), after three days. A statistical treatment (Analysis of Variance, ANOVA table) for d-limonene levels in the juice containing the ALATHON ®LDPE film is presented in Table 18. As shown, there were statistically significant differences between the d-limonene levels in the juice containing the ALATHON ® LDPE film at a confidence interval of 99 percent. However, the ANOVA treatment also showed that there was no significant difference between d-limonene levels after 3 days storage. The d-limonene concentration in the juice containing the SELAR ®EVOH film strips showed a relative decrease of 18 percent after 24 days storage. The results of statistical treatment (ANOVA table) for d-limonene levels in the juice containing the SELAR ®EVOH film strips is presented in Table 19. Statistical analysis showed that there were significant differences between the d-limonene concentration in the juice containing the SELAR ®EVOH film strips after 3 days storage, at a confidence interval of 99 percent. With regard to the SELAR ® 00- PET film sample, statistical treatment of the 53 data showed there was no significant difference between d- limonene levels in the juice containing the SELAR ®’Co- PET film strips over the entire storage time (Table 20), at a confidence interval of 99 percent. A statistical treatment (ANOVA table) was also carried out between the samples, that is, the control juice, the juice containing the ALATHON ® LDPE film strips, the juice containing the SELAR ®EVOH film strips and the juice containing the SELAR ®Co-PET film strips. As shown in Table 21, there was a significant difference between d-limonene levels in the control juice and the juice containing the ALATHON ®LDPE film strips, as well as the control juice and the juice containing the SELAR ®EVOH film strips. However, there was no significant difference between limonene levels in the control juice and the juice containing the SELAR ®Co- PET film strips, at a confidence interval of 99 percent. Significant differences in d-limonene levels existed between the juice samples containing the different polymer films. Sorbed d-limonene levels in the SELAR ® Co- PET and the SELAR ®EVOH samples immersed in the juice product were also determined experimentally. For the ALATHON ® LDPE film sample, however, recovery studies showed very rapid desorption of d-limonene from the film, following its removal from the juice (APPENDIX IV). Apparently, the desorption of d-limonene occurs during the sampling and washing process 54 * Significant at 99 % Table 18. ANOVA table for d-limonene concentration in the juice, containing ALATHON ® LDPE strips. Sourse Sum of Squares d.f. Mean Square F - test TR 1489.238 5 297.848 39.855 E 149.464 20 7.473 Total 1638.702 25 Storage Mean Count Std. Dev. Std, Error Timegdays) 0 45.830 6 4.686 1.913 1 34.965 4 2.28 1.14 3 27.345 4 1.322 0.661 6 26.972 4 2.426 1.213 14 27.622 4 0.456 0.228 24 28.060 4 0.422 0.211 Comparison Mean Difference F-test 0 vs. 1 10.865 * 0 vs. 3 18.485 * 0 vs. 6 18.858 * 0 vs.14 18.208 * 0 v3.24 17.770 * 1 vs. 3 7.620 * 1 vs. 6 7.992 * 1 vs.14 7.342 * 1 v3.24 6.905 * 3 vs. 6 0.373 3 vs.14 -0.277 3 v3.24 -0.715 6 vs.14 -0.650 6 v3.24 -1.088 14 v3.24 -0.438 55 Table 19. ANOVA table for d-limonene concentration in the juice, containing SELAR ® EVOH strips. Sourse Sum of Squares d.f. Mean Square F -— test TR 198.902 5 39.78 4.6 E 172.966 20 8.648 Total 371.867 25 Storage Mean Count Std. Dev. Std. Error Time(days) 0 45.830 6 4.686 1.913 1 41.458 4 1.698 0.849 3 39.208 4 2.267 1.133 6 42.015 4 1.717 0.859 14 43.860 4 2.664 1.332 24 37.978 4 1.727 0.864 Comparison Mean Difference F-test 0 vs. 1 4.373 0 vs. 3 6.623 * 0 vs. 6 3.815 0 vs.14 1.970 0 vs.24 7.853 * 1 vs. 3 2.250 1 vs. 6 -0.557 1 vs.14 -2.403 1 vs.24 3.480 3 vs. 6 -2.807 3 vs.14 -4.653 3 vs.24 1.230 6 vs.14 -1.845 6 vs.24 4.037 14 vs.24 5.882 * Significant at 99 % 56 Table 20. ANOVA table for d-limonene concentration in the juice, containing SELAR ® Co- PET strips. Sourse Sum of Sglares d.f. Mean Square F - test TR 91.672 5 18.334 2.091 E 175.337 20 8.767 Total 267.008 25 Storage Mean Count Std. Dev. Std. Error Time(days) 0 45.830 6 4.686 1.913 1 42.340 4 2.447 1.223 3 41.653 4 0.945 0.472 6 46.103 4 1.922 0.961 14 44.805 4 0.364 0.182 24 46.743 4 3.338 1.669 Comparison Mean Difference F-test 0 vs. 1 3.490 0 vs. 3 4.177 0 vs. 6 -0.272 0 vs.14 1.025 0 vs.24 -0.912 1 vs. 3 0.687 1 vs. 6 -3.763 1 vs.14 -2.465 1 vs.24 -4.403 3 vs. 6 -4.450 3 vs.14 -3.152 3 vs.24 -5.090 6 vs.14 1.298 6 vs.24 -0.640 14 vs.24 -1.938 * Significant at 99 % 57 Table 21. ANOVA table for d-limonene concentration in the juice, following contact with test films. Sourse Sum of Squares d.f. Mean Square F - test TR 3538.633 3 1179.544 138.395 E 647.750 76 8.523 Total 4186.383 79 Sample Mean Count Std. Dev. Std. Error Juice (J) 46.020 20 2.62 0.586 W/LDPE (L) 28.993 20 3.407 0.762 W/EVOH (E) 40.904 20 2.81 0.628 W/Co-PET(PH, 44.329 20 2.78 0.622 , Comparison Mean Difference F-test (J) vs.(L) 17.027 * (J) vs.(E) 5.116 * (J) vs.(P) 1.692 (L) vs.(E) -11.911 * (L) vs.(P) -15.335 * (E) vs.(P) -3.425 * * Significant at 99 % 58 prior to extraction. Therefore, sorbed concentration levels of d-limonene in the ALATHON ® LDPE film were determined by the difference method (Kashtock, et al., 1980). The amount of d-limonene sorbed by the plastic films is summarized in Table 22 and presented graphically in Figure 7. Sorption of d-limonene by the films was observed within one day. After three days storage, sorption by the ALATHON ® LDPE film had attained equilibrium. Six days were required to reach saturation equilibrium for the SELAR ®EVOH film. The amounts of d-limonene sorbed by the test films at equilibrium were 16.4 mg/g for the ALATHON ® LDPE and 9.7 mg/g for the SELAR ® EVOH. After 24 days, 0.03 mg/g d-limonene was sorbed by the SELAR ®’Co- PET film. D-limonene is readily sorbed by polyethylene, because the chemical affinity of hydrocarbons such as d-limonene for polyethylene is strong (Ikegami, 1987) . The ALATHON ® LDPE film was found to contain 0.007 mg/g geranial after twenty four days. Neral and geranial were not found in the other films during twenty four days storage. The partition coefficient (Kp) was calculated for d— limonene and the respective orange juice/polymer contact film systems. Kp values were determined using the following expressions: 59 Table 22. The amount of d-limonene sorbed by the sample films following immersion in orange juice, at 219C. Limonene Concentration (mc/q) in Film Storage (a) Time ALATHON ® SELAR ® SELAR ® (days) LDPE EVOH Co—PET X :t s.d. X :i s.d. X s.d. 0 0.00 0.000 0.000 1 11.74 2.66 6.732 0.839 0.005 0.002 3 17.03 3.05 7.394 2.040 0.007 0.001 6 15.51 5.51 9.600 0.722 0.017 0.004 14 14.97 1.66 10.20 1.23 0.017 0.004 24 13.64 3.41 9.261 1.532 0.027 0.006 (a) Calculated by the difference method. 20 E“ tn 1 E 6 (I) <1) 2;. 5 m 12 E r-l -H in C -:-l (3 c: O U (D 5 4 C.‘ 0 e "-1 A 60 P-F—l Storage Time (days) IJJI4IIIIII‘J 3 6 9 12 15 18 21 24 27 x ALATHON® LDPE ‘ SELAR® EVOH ° SELAR® Co-PET Figure 7. The sorption of d-limonene by the films as a function of storage time. 61 [Climoneneilpolymer Kp(differential) - [Climonene juice (6) c . where [ lmoneneJPOllflner : concentration of d-limonene in the film at equilibrium (mg/g), determined by difference. C ' a g o I I: 1m°nene jmce : concentration of d-llmonene in the juice at equilibrium (mg/g). The partition coefficient KP(experimental) was determined from: [C(e) limonene]polymer Kp(experimental) = [C(e) limoneneruice (7) C o where [ ‘6’) lm°nen°JP°lYmer : concentration of d-limonene in the film from experimental data at equilibrium (mg/g). C ' . [ (e) lmmene jume : concentration of d-limonene in the juice at equilibrium (mg/g). For example, Kp(differential) for the SELAR ®EVOH is calculated as follows: Ke = ([Caq] initial- [Caq]eq) * V01.aq.phaSe/Wt pOlymer/ [Caq] eq (1) KP(differential) = (45.83 - 41.28)(mg)/0.60(g)/0.154 (mg/g) = 49.2 62 where: 45.83 equals the quantity of d-limonene in the juice (mg) at 0 day storage and 41.28 equals the average quantity of d-limonene in the juice (mg) at equilibrium, 0.60 equals the weight of the SELAR ® EVOH in contact with juice (g), and 0.154 equals the average d-limonene concentration in the juice (mg/g) at equilibrium. On the other hand, KP(experimental) of the SELAR ®EVOH is calculated in the following way. Kp (experimental) = 9.687 (mg/9) / 0.154 (mg/g) = 62.9 where: 9.687 equals the average d-limonene concentration in the film (mg/g) at equilibrium (6 - 24 days) and 0.154 equals the average d—limonene concentration in the juice (mg/g). The partition coefficients KP(experimental) and Kp(differential) for the respective film samples are summarized in Table 23. The ratios of KP(experimental) (Kp (e)) and Kp(differential) (Kp (d)) are also presented. The ratio (Kp(e)/Kp(d)) for the SELAR ®EVOH was 1.277 and that for the SELAR ® Co- PET was 0.733. The differences obtained between the differential and experimental partition coefficient values were attributed to experimental error, such as desorption of d-limonene from the sample films occurring during the handling and washing procedures. 63 .mmmo «N can vH Ho mcoHumubcwocoo momnm>¢ on .mmmo em on m Eouu mcpomuuamocoo oomuo>¢ Any .mmmo gm on m Sony mGOHbmuucoocoo momum>¢ Adv mm>.o n>N.H AIV on QM \ Adv mm ohH.o m.mv n.mmH AIV AHmHucouommHov mm mNH.o o.mm AIV AHmucoEHanxmv QM 00H: m mcmcoEHH do oosH.o ammH.o mNOH.o Ao\mev A or A v A V A V Am m V mod .5. ocoaoEHH B o o. D m. m h . H E m o m n m m \ wMHbcmuouHHoo noemHom ocmcoEHH o . . m o A vmmo o Anyhow m A x 8. AHmucoEHummxmn: IHmmIoo mo>m mmom 9 Emm @ gmm @ 223.3 .mEoumam EHHH uomucoo umemHom\onow omcmuo who can .mcocoEHHuo now mosHm> bcoHoHuHooo coHuHuqu 0:9 .mm oHnme 64 For a linear model, the equilibrium concentration of penetrant in the packaging material, resulting from contact with the contact phase, is directly proportional to the initial penetrant concentration and can be estimated by solution of equation (8) (Gilbert et al., 1975; Giacin, 1980). [ch _ET]C_°lC_ e- E J, Wp (8) KP where: [KflPe concentration of penetrant in polymer phase at equilibrium [Iikb = initial concentration of penetrant in the contact phase WC and Wp = weight of contact phase and polymer, respectively - partition coefficient defined as the concentration of penetrant in polymer at equilibrium divided by the equilibrium concentration of penetrant in the contact phase. 65 Influence of d-Limonene Absorption on Mbchanical Properties of Plastic Films The amount of d-limonene in the film samples was measured prior to determining the films mechanical properties. The influence of sorption on the modulus of elasticity, yield stress, stress at 100 percent elongation, tensile strength, elongation at break and heat seal strength was determined for the three test films. The effect of d-limonene sorption on mechanical properties of each plastic film was statistically evaluated by one way analysis of variance (APPENDIX V). Results were compared as a function of d-limonene concentration for the three test films. We (1) Modulus of Elasticity The modulus of elasticity of the ALATHON ® LDPE film determined as a function of d-limonene concentration is shown in Table 24. The modulus of elasticities of the SELAR ®EVOH and SELAR ® Co- PET films determined as a function of d- limonene concentration are shown in Tables 26 and 27, respectively. For better illustration, the relative percent change in modulus of elasticity as a function of sorbed limonene concentration for the test films is presented graphically in Figures 9 - 12. Results of statistical 66 evaluation of the modulus of elasticity data for the sample films are shown in Table 25, 28 and 29. The results show that limonene sorption significantly affected the modulus of elasticity for the SELAR® EVOH film in both directions (Machine direction (MD) and Cross machine direction (CD)). The absorption of d-limonene by the SELAR ® EVOH decreased the stiffness of the film. However, it did not significantly affect the modulus for the ALATHON ® LDPE film. Results for the SELAR ® Co- PET film were mixed. A significant difference was observed when 0.003 and 0.019 mg/g of d- limonene were sorbed by the film. (2) Yield Stress Values of the yield stress of the test films immersed in orange juice and stored at 21°C are presented in Tables 30 and 32. The results of statistical evaluation of the yield stress data are shown in Tables 31 and 33. The relationship between the yield stress and d-limonene concentration for the test films is shown in Figures 13 - 14. The SELNR‘D Co-PET film did not exhibit a yield point, thus no yield stress data were recorded. Significant differences were observed in machine and cross machine directions for the SELAR ® EVOH. 67 4‘ Va coHuooqu ocHgome mmouu coHuoouHo ocHnomz DU 02 muHoHumeo Ho msHsooE may :H omcmno unmouom w>HumHou ”mHmonucmumm mucoEousmme me Ho mcoHumH>op oumocmum pom memos mum muHSmmu was A0.00. AH.00H0 A0.00H0 A0.000 A0.00H0 0H.0 H 0H.H 0H.0 H 00.H 00.0 H em.H 0H.0 H 00.H 0H.0 H 00.H Aoo. AH.00. A0.000 A0.00H0 A0.000 Am.000 A0.00H0 0H.0 H 0H.H 00.0 H 00.H 00.0 H -.H HH.0 H H~.H 0H.0 H 00.H 0H.0 H HN.H A920 mmoqszomefic om H x om H x om H x om H x om H x cm H x deamw. m0~.m 000.0 H00.H 000.0 H0~.0 000.0 EHHm cH Am\msv .oaoo mcocoEHq .ooHN um momuoum mcHHso ooHsfl omcmuo cH oomuoEEH EHHH ES s 20542 uou :3 30H x s 33333 no 03285 5 mmcmso .00 382. 68 Table 25. Statistical evaluation of the change in modulus of elasticity for ALATHON ®>LDPE film. Mean Difference (MD) (9D) E(O) - E(0.281) 0.14 i 0.21 0.03 i 0.25 E(O) - E(0.474) 0.00 i 0.21 -0.11 i 0.25 E(O) - E(l.461) -0.01 i 0.21 -0.05 i 0.25 E(O) - E(3.046) 0.13 i 0.21 *0.30 i 0.26 E(O) - E(5.203) 0.07 i 0.21 E(0.281) - E(0.474) -0.14 i 0.21 -O.14 i 0.25 E(0.281) - E(1.461) -0.15 i 0.21 -0.08 i 0.25 E(0.281) - E(3.046) -0.01 i 0.21 *0.27 i 0.26 E(O.281) - E(5.203) -0.07 i 0.21 E(0.474) - E(l.461) -0.01 i 0.21 .06 i 0.25 E(O.474) - E(3.046) 0.13 i 0.21 *0.41 i 0.26 E(0.474) - E(5.203) 0.07 i 0.21 , E(1.461) - E(3.046) 0.14 i 0.21 *-0.35 i 0.26 E(1.46l) - E(5.203) 0.08 i 0.21 E(3.046) - E(5.203) -0.06 i 0.21 * Significant difference at 97 percent E(O) = mean value of initial E(O.281) E(O. E(l. E(3. E(S. m: CD = 474) 461) 046) 203) Machine direction me an me an me an me an me an value value value value value containing 0.281 containing 0.474 containing 1.461 containing 3.046 containing 5.203 Cross machine direction confidence intervals mg/g mg/g mg/g mg/g mg/g of d-limonene of d-limonene of d-limonene of d-limonene of d-limonene _-.. s ' : 69 coHuoouHo ocHnomE mmono coHuoouHo mcHnomz DO DZ muHoHummHo mo msHsooE on» cH omcmno ucoouom o>HumHoH "mHmonucwumm mucmEoHSmmoE me Ho mcoHumH>oo oumocmum pom momma mum muHSmmH one A0.000 A0.000 A0.000 A0.00. 00.0000 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 .00. A0.00. A0.000 .0.00. A0.000 A0.000 l0.0000 _ 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 lose mo>m®m€0Mm 00 H x 00 H x 00 H x 00 H x 00 H x 00 H‘x 000500 000.0 000.0 000.0 000.0 000.0 0 EHHm :H Am\oev .ocou ocmcoEHq .omHN um ommuoum mcHusU ooHsn wmcmno :H ommHoEEH EHHH mo>m 9 gum you AHmQ vHumHmu "mHmmnuamHmm mucoEmHSmmmE cop mo mcoHu0H>wU oumocmum ocm momma mum mqumoH one Am.wmv Ab.mHHv Am.mmv Am.NHHv Ao.00Hv hm.o H mm.m Hv.o H m.HH mv.o H v>.¢ HH.o H v.HH v>.o H H.0H AQUV A>.mOHV AH.mHHv AN.NOHV AH.omHv Ao.ooHv mH.H H H.0H HH.H H o.HH hm.o H mm.m 0N.H H N.HH vv.H H Nm.m AQEV Hmmloo@m44mw om H x Om H x mm H x cm H x Om H x mHCEmm mNo.o mHo.o MHo.o moo.o ooo.o EHHm CH Am\mev .ocou ocmcoEHq .ooHN um oomuoum mcHnso ooHsn wmcmuo cH oomuoEEH EHHH Emmaou ® 02.0mm Hon AHmm v.50 x 2 mpHoHumMHo mo 20.00608 5 omcmco .90 380.0. 71 Table 28. Ststistical evaluation of the change in modulus of elasticity for SELAR ® EVOH film. Mean Difference (MD) (CD) E(O) - E(2.037) *0.33 i 0.22 *1.29 i 0.58 E(O) - E(2.633) *0.44 i 0.23 *1.16 i 0.58 E(O) - E(4.310) *1.35 i 0.22 *1.40 i 0.58 E(O) - E(6.188) *1.02 i 0.22 *1.52 i 0.58 E(O) - E(9.261) *2.09 i 0.22 E(2.037) - E(2.633) 0.11 i 0.22 -0 13 i 0.58 E(2.037) - E(4.310) *1.02 i 0.21 0.11 i0.58 E(2.037) - E(6.188) *0.69 i 0.21 0 23 i 0.58 E(2.037) - E(9.261) *1.76 i 0.21 E(2.633) - E(4.310) *0.91 i 0.22 0 24 i 0.58 E(2.633) - E(6.188) *0.58 i 0.22 0 36 i 0.58 E(2.633) - E(9.261) *1.65 i 0.22 E(4.310) - E(6.188) *-0.32 i 0.21 0.12 i 0.58 E(4.310) - E(9.261) *0.74 i 0.21 E(6.188) - E(9.261) *1.07 i 0.21 * Significant difference at 97 percent confidence intervals E(O) = mean value of initial E(2.037) = mean value containing 2.037 mg/g of d-limonene E(2.633) = mean value containing 2.633 mg/g of d-limonene E(4.310) = mean value containing 4.310 mg/g of d-limonene E(6.188) = mean value containing 6.188 mg/g of d-limonene E(9.261) = mean value containing 9.261 mg/g of d-limonene MD Machine direction CD Cross machine direction 72 Table 29. Statistical evaluation of the change in modulus of elasticity for SELAR ®>Co-PET film. Mean Difference (MD) (CD) E(O) - E(0.008) -1.87 i 2.68 *-1.27 i 1.05 E(O) - E(0.013) -0.21 i 2.68 0.37 i 1.05 E(O) - E(0.019) -1.67 i 2.68 *-1.74 i 1.00 E(O) - E(0.025) -0.81 i 2.68 0.14 i 1.05 E(0.008) - E(0.013) 1.66 i 2.80 *1.64 i 1.10 E(0.008) - E(0.019) 0.18 i 2.80 -0.47 i 1.05 E(0.008) - E(0.025) 1.06 i 2.80 *1.41 i 1.10 E(0.013) - E(0.019) -1.48 i 2.80 *-2.10 i 1.05 E(0.013) - E(0.025) -0.60 i 2.80 -0.23 i 1.10 E(0.019) — E(0.025) 0.88 i 2.80 *1.88 i 1.05 * Significant difference at 97 percent E(O) E(0.008) E(0.0l3) E(0.019) E(0.025) MD CD mean value of initial me an mean mean me an value value value value Machine direction Cross machine direction containing 0.008 containing 0.013 containing 0.019 containing 0.025 confidence intervals mg/g of d-limonene mg/g of d-limonene mg/g of d-limonene mg/g of d-limonene 73 120 6 Machine direction 40 . l . J . | 1 J , ‘ Cross machine direction Relative % Change in the Modulus of Elasticity Limonene Conc. (mg/g) Figure 8. Relationship between modulus of elasticity and d—limonene concentration for SELAR ® EVOH film. 74 'f L 120 c 5‘ 0 .8 L *1 / v ‘0’ ' o m ‘3 O 0 1006, . ° 0 (0 :3 r-l :5 'o o E: .2 80 . 4.) c 0H o F ow E 8 60. 0P 0 > "-1 3 9 iMachine direction H g 40 1 l 4 J J 9 Cross machine direction 0.00 0.01 0.02 0.03 Limonene Conc. (mg/g) Figure 9. Relationship between modulus of elasticity and d-limonene concentration for SELAR ® Co-PET film. 75 100 80 Relative % Change in the Modulus of Elasticity b A 60 - ALATHON ® 8 LDPE(MD) ' SELAR ® ‘ EVOH(MD) 40 J I I 111111 J 1 1 llllll 1 JJ lllllr . Co-PET (MD) .01 .1 1 10 Limonene Conc. (mg/g) Figure 10. Relationship between modulus of elasticity and d-limonene concentration for the test films (MD). 76 120 100 80 Relative % Change in the Modulus of Elasticity 60 . . ALATHON ® LDPE(CD) ' SELAR ® ‘ EVOH(CD) 40 1 1 1 1 1111' 1 1 1 11111] J 1 1 1 1111 . CO'PET (CD) .01 .1 1 1o Limonene Conc. (mg/g) Figure 11. Relationship between modulus of elasticity and d-limonene concentration for the test films (CD). .M‘B mi “ I 77 (3) Stress at 100 percent elongation The values of the stress at 100 percent elongation for the test films immersed in orange juice and stored at 21°C are shown in Tables 34 - 35. Statistical analysis of the stress at 100 percent elongation data was carried out and the results summgrized in Table 36. The relationship between stress at 100 percent elongation and sorbed d—limonene levels for the respective test films is shown in Figures 15 - 16. The absorption of d-limonene was found to significantly affect the stress at 100 % elongation of the SELAR ® EVOH film (MD, CD) and the ALATHON ® LDPE film (CD). The SELAR ® Co-PET film failed before reaching 100 % elongation and thus was not evaluated. (4) Tensile Strength The influence of sorption of d-limonene on the tensile strength of the sample films was determined and results summarized in Tables 37, 39 and 40. The relationship between tensile strength and d—limonene concentration for the test films is shown in Figures 17 - 19. The results of statistical evaluation of the change in tensile strength for the films are summarized in Tables 38, 41 and 42. As shown, the sorption of d-limonene did not significantly effect the tensile strength of the three test films. (5) Elongation at Break Values for percent elongation at break for the films as a function of sorbed limonene levels are presented in Tables 78 coHuooHHo ocHnomE mmouo coHuooHHo mcHnomz DO DZ mmouuw oHoH> on» cH omcmzo usoouma o>HumHon “mHmocucmumm mucoEonsmmmE no» mo mcoHHMH>mo oumocmum paw mcmoe mum muHsmoH one A0.0000 A0.000 A0.000 A0.000 A0.000 A0.0000 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0 00.0 Amos A0.000 A0.000 A0.000 A0.00v A0.000 A0.000 A0.000. 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0 00.0 Aozc 00000200000000 00 H x swimwww 00 w x 00 H x 00 H x 00 H x mm H x 00mEmm 000.0 000.0 000.0 000.0 000.0 000.0 000.0 EHHm cH Am\mEV.ocoo ococoEHH .HEHN um momuoum mcHuso moHsfl mmcmuo CH omemEEH EHHH 0000 e 2000.00.00 000 A000 0.00 x 00 000000 000000 :0 090008 .00 00000.0. 79 Table 31. Statistical evaluation of the change in yield sress for ALATHON ® LDPE film. Mean Difference (MD) (CD) Y(0) - Y(0.143) *0.24 i 0.20 0.00 i 0.17 Y(O) - Y(O.281) 0.15 i 0.20 0.18 i 0.17 Y(0) - Y(0.474) *0.21 i 0.20 0.08 i 0.17 Y(0) - Y(l.461) 0.04 i 0.20 0.03 i 0.17 Y(0) - Y(3.046) 0.17 i 0.20 -0.02 i 0.17 Y(0) - Y(5.203) 0.05 i 0.20 Y(0.143) - Y(0.281) -0.09 i 0.20 *0.18 i 0.17 Y(0.143) - Y(0.474) -0.03 i 0.20 0.08 i 0.17 Y(0.143) - Y(l.46l) -0.20 i 0.20 0.03 i 0.17 Y(0.143) - Y(3.046) -0.07 i 0.20 -0.02 i 0.17 Y(0.143) - Y(5.203) -0.19 i 0.20 Y(0.281) - Y(0.474) 0.06 i 0.20 -0.10 i 0.17 Y(0.281) - Y(1.461) -0.11 i 0.20 -0.16 i 0.17 Y(0.281) - Y(3.046) 0.02 i 0.20 *-O.20 i 0.17 Y(0.281) - Y(5.203) -0.10 i 0.20 Y(0.474) - Y(l.461) -0.17 i 0.20 -0.06 i 0.17 Y(0.474) - Y(3.046) -0.04 i 0.20 -0.10 i 0.17 Y(0.474) - Y(5.203) -0.16 i 0.20 Y(1.461) - Y(3.046) 0.13 i 0.20 0.04 i 0.17 Y(l.46l) - Y(5.203) 0.00 i 0.20 Y(3.046) - Y(5.203) -0.12 i 0.20 * Significant difference at 97 percent confidence intervals Y(0) = mean value of initial Y(0.143) Y(0.281) Y(0.474) Y(1.461) Y(3.046) Y(5.203) MD CD me an me an me an me an me an me an value value value value value value Machine direction Cross machine direction containing containing containing containing containing containing 0.143 0.281 0.474 1.461 3.046 5.203 mg/g mg/g mg/g mg/g mg/g mg/g of d-limonene of d-limonene of d-limonene of d-limonene of d-limonene of d-limonene 1.2”- 80 no 02 noHuoouHo oanomE mwouo noHuoouHo oanooz omouum oHoHe onu nH omnono unoouom o>HuoHou umHmonunoHom manoeousmooe me mo mnoHuoH>oo Unopnmum ono wnmoe ouo muHsmoH one A0.000 10.000 A0.000 A0.000 A0.000 A0.0000 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 Amos .0.000 A0.000 A0.000 A0.000 A0.000 A0.000 A0.0000 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 Ans. mot/mega 00.H x. 00 H x 00 H x 00 H x 00 H x 00 H x 00 H x» 00m200 000.0 000.0 000.0 000.0 000.0 000.0 000.0 EHHm nH Ao\mev .onoo ononoEHn .omHN um omououo mnHuso ooHsn omnouo nH pomuoeeH EHHH 00020 e 000.000 000 A000 0.00 x 00 009.50 60000 :0 00005 .00 030.0. 81 Table 33. Statistical evaluation of the change in yield strss for SELAR ® EVOH film. Mean Difference (MD) (CDL4, Y(0) - Y(2.037) *0.65 i 0.34 *0.26 i 0.21 Y(0) - Y(2.412) *0.40 i 0.34 0.08 i 0.21 Y(0) - Y(2.633) 0.30 i 0.34 0.00 i 0.21 Y(0) - Y(4.310) *0.65 i 0.34 *0.41 i 0.21 Y(0) - Y(6.188) 0.33 i 0.34 0.05 i 0.21 Y(0) - Y(9.261) *1.03 i 0.34 Y(2.037) - Y(2.412) -0.25 i 0.34 -0.18 i 0.21 Y(2.037) - Y(2.633) -0.34 i 0.34 *-0.26 i 0.21 Y(2.037) - Y(4.310) 0.00 i 0.34 0.16 i 0.21 Y(2.037) - Y(6.188) -0.32 i 0.34 -0.21 i 0.21 Y(2.037) - Y(9.261) *0.38 i 0.34 Y(2.412) - Y(2.633) -0.10 i 0.34 -0.07 i 0.21 Y(2.412) - Y(4.310) 0.25 i 0.34 *0.34 i 0.21 Y(2.412) - Y(6.188) -0.08 i 0.34 -0.03 i 0.21 Y(2.412) - Y(9.261) *0.63 i 0.34 Y(2.633) - Y(4.310) *0.35 i 0.34 *0.43 i 0.21 Y(2.633) - Y(6.188) 0.02 i 0.34 0.05 i 0.21 Y(2.633) - Y(9.261) *0.72 i 0.34 Y(4.310) - Y(6.188) -0.33 i 0.34 *-0.38 i 0.21 Y(4.310) - Y(9.261) *0.38 i 0.34 Y(6.188) - Y(9.261) *0.70 i 0.34 * Significant difference at 97 percent confidence intervals Y(0) = mean value of initial Y(2.037) = mean value containing 2.037 mg/g of d-limonene Y(2.412) = mean value containing 2.412 mg/g of d-limonene Y(2.633) = mean value containing 2.633 mg/g of d-limonene Y(4.310) = mean value containing 4.310 mg/g of d-limonene Y(6.188) = mean value containing 6.188 mg/g of d-limonene Y(9.261) = mean value containing 9.261 mg/g of d-limonene MD Machine direction CD Cross machine direction 82 120 U) U) H 4.) a) 3 100 o 01-1 >‘ o X .n 4.) n E 80 . o ow n o .n U W 3 60. 'H 4., o H o m D X Machine direction 40 n l 1 l 1 l n l 1 X Cross machine direction 0 2 4 6 8 10 Limonene Conc. (mg/g) Figure 12. Relationship between yield stress and d-limonene concentration for ALATHON ® LDPE film. Relative % Change in the Yield Stress 120 60 40 83 8 Machine direction ‘ Cross machine Limonene Conc. (mg/g) direction 10 Figure 13. Relationship between yield stress and d-limonene concentration for SELAR ® EVOH film. 84 Table 34. Change in stress at 100 percent elongation (x 1003 psi) for ALATHON ® LDPE film immersed in orange juice and stored at 21%:. Limonene Conc. (mg/g) in Film 0.000 3.046 5.203 Sample X 1 SD X 1 SD X 1 SD ALATHON®LDPE (MD) 2.10 i 0.18 1.97 i 0.09 2.01 i 0.12 (100.0) (93.8) (96.7) (CD) 1.76 i 0.08 1.56 i 0.15 (100.0) (88.6) The results are means and standard deviations of ten samples Parenthesis: relative percent change in the stress at 100 % elongation MD = Machine direction CD = Cross machine direction 85 Table 35. Change in stress at 100 percent elongation (x 10"3 psi) for SELAR ® EVOH film immersed in orange juice and stored at 219C. Limonene Conc.(mg/g) in Film 0.000 6.188 9.261 Sample X i SD X i SD X 1 SD SELAR®EVOH (MD) 2.97 i 0.30 2.63 i 0.18 2.27 i 0.10 (100.0) (88.5) (76.4) (CD) 2.53 i 0.08 2.23 i 0.05 (100.0) (88.1) The results are means and standard deviations of ten samples Parenthesis: relative percent change in the stress at 100 % elongation MD = Machine direction = Cross machine direction 86 Table 36. Statistical evaluation of the change in stress at 100 % elongation for ALATHON ® LDPE and SELAR ® EVOH film. Mean ALATHON®LDPE Difference MD CD S(O) - S(3.046) 0.14 i 0.17 *0.20 i 0.13 S(O) - S(5.203) 0.09 i 0.17 S(3.046) - S(5.203) -0.04 i 0.17 Mean SELAR®EVOH Difference MD CD S(O) - S(6.188) *0.41 i 0.26 *0.36 i 0.01 S(O) - S(9.261) *0.84 i 0.26 S(6.18811: S(9.261) *0.43 i 0.26 * Significant difference at 97 percent confidence intervals S(O) S(3.046) S(5.203) S(O) S(6.188) = mean value containing 6.188 mg/g of d-limonene S(9.261) MD CD = mean value of initial = mean value of initial Machine direction Cross machine direction mean value containing 3.046 mg/g of d-limonene mean value containing 5.203 mg/g of d-limonene mean value containing 9.261 mg/g of d-limonene 87 120 d0 O O H 4.) o 8 o 100 1‘3 ”1 X a1n , n o qu JJ n¢u “2‘ mo 80h 504 ntn o n o . 69 f3 01 60 . 4.) o H o m X Machine direction 40 1 I 1 I 1 l 11 l 1 1 X Cross machine 0 2 4 6 8 1O direction Limonene Conc. (mg/g) Figure 14. Relationship between stress at 100 % elongation and d-limonene concentration for ALATHON ® LDPE film. 88 120 8 Relative % Change in the Stress at 100 % Elongation 8 A 60 P A Machine direction 40 1 I 1 I J I 1 I 1 I Cross machine direction 0 2 4 6 8 10 Limonene Conc. (mg/g) Figure 15. Relationship between stress at 100 % elongation and d-limonene concentration for SELAR ®EVOH film. 89 noHuooHHo oanooE moouo nOHuooHHo oanooz GU OE npmnonuo oHHmnou onu nH omnmno unoouod o>HuoHoH "mHmonunouom munoeonomoos non Ho mnoHuoH>oo ouoonoum ono onooe oum muHsmou one A0.000 Ae.000 A0.000 A0.000 A0.000 A0.0000 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 Aooc A0.0000 A0.0000 A0.000. 10.0000 A0.0000 A0.000 A0.0000 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 00.0H00.0 Aozc 0000002800000 00 H x 00 H x ow H x. 00 H x. 00 H x omIH. x, 00 H x o0osmm. 000.0 000.0 000.0 000.0 000.0 000.0 000.0 EHHm nH Am\mev.onou ononoeHn .ueHN no omououm mnHusp o0H5n omnmuo nH oomuoEEH EHHH 08.0 e zomefin Hon :3 0.00 x 00 505.000 300.80 :0 oocmno .00 3000.0 9O Table 38. Statistical evaluation of the change in tensile strength for ALATHON ® LDPE film. Mean Difference (MD) (CD) TS(O) - TS(0.143) 0.16 i 0.39 0.13 i 0.29 TS(O) - TS(0.281) -0.20 i 0.39 0.22 i 0.29 TS(O) - TS(0.474) -0.05 i 0.39 *0.45 i 0.29 TS(O) — TS(1.461) -0.07 i 0.39 0.01 i 0.29 TS(O) - TS(3.046) -0.14 i 0.39 0.17 i 0.29 TS(O) - TS(5.203) -0.04 i 0.39 TS(0.143) - TS(0.281) -0.36 i 0.39 0.09 i 0.29 TS(0.143) - TS(0.281) -0.21 i 0.39 *0.31 i 0.29 TS(0.143) - TS(0.474) -0.23 i 0.39 -0.13 i 0.29 TS(0.143) - TS(1.461) -0.30 i 0.39 0.04 i 0.29 TS(0.143) - TS(3.046) -0.20 i 0.39 TS(0.281) - TS(0.474) -0.15 i 0.39 -0.23 i 0.29 TS(0.281) - TS(1.461) 0.13 i 0.39 -0.21 i 0.29 TS(0.281) - TS(3.046) 0.06 i 0.39 -0.05 i 0.29 TS(0.281) - TS(5.203) 0.16 i 0.39 TS(0.474) - TS(1.461) -0.02 i 0.39 *-0.44 i 0.29 TS(0.474) - TS(3.046) -0.09 i 0.39 -0.28 i 0.29 TS(0.474) - TS(5.203) 0.01 i 0.39 TS(1.461) - TS(3.046) -0.07 i 0.39 0.16 i 0.29 TS(1.461) — TS(5.203) 0.03 i 0.39 TS(3.046) - TS(5.203) 0.01 i 0.39 * Significant difference at 97 percent confidence intervals TS(O) = mean value of initial TS(0.143) = mean value containing 0.143 mg/g of d-limonene TS(0.281) = mean value containing 0.281 mg/g of d-limonene TS(0.474) = mean value containing 0.474 mg/g of d-limonene TS(1.461) = mean value containing 1.461 mg/g of d-limonene TS(3.046) = mean value containing 3.046 mg/g of d-limonene TS(5.203) = mean value containing 5.203 mg/g of d-limonene MD Machine direction CD = Cross machine direction 91 no Q2 noHuooHHo oanooE mmouo noHuoouHo oanooz numnonum oHHmnou onu nH omnmno unoouom o>HpoHoH ”mHmonunonom munoeoHSmmoE no» no wnoHuoH>oo oumonmum ono mnooe ouo muHsmon one Ae.mmv Am.emv Am.NOHV Am.mmv AN.mmv Ao.OOHV HN.onm.m Nm.oHNw.m Hv.oHeN.v ov.oHvH.v Hv.oHoe.m em.oHVH.v AQUV Am.va Am.Hmv Am.omv Am.mmv Ao.vmv Am.omv Ao.OOHV mm.oHvH.v mm.lom.v mv.onm.v e¢.one.v vm.oHHh.v o>.ono.v Nv.oHHo.m. AGE. mo>m©gmm Om H x mm H x mm H x mm H x ow H x (mm H, x Om H x onEmm HmN.m mmH.o OHm.v mmm.m NHv.N bmo.m ooo.o EHHm nH Am\mev.onoo ononoeHH .oon no omouopm manso ooHsn omnmno nH oomnoEEH EHHH 0005 @mnqmw How AHmm mHuoHoH "ononunouom mucoEonsmooe now no mnoHumH>oo ouoonoum ono mnooe ouo muHsmoH one A0.0000 A0.0000 Am.0000 Am.000v Ae.0000 Ao.0000 00.0 00.0 00.0 00.0 00.0 00.0 00.0 00.0 00.0 00.0 00.0 m0.m Aouv A0.0o0v A0.0000 Ae.m00v Am.0000 Ae.000v Ao.m000 Ao.000v 00.0 m0.0 00.0 00.0 00.0 00.0 00.0 00.0 0m.o 00.0 00.0 00.0 m0.o 00.0 Aozv emmuoo@mn.0Mm cm N cm x cm x cm x 00m x cm x cm x 003.00% 000.0 000.0 000.0 000.0 000.0 000.0 000.0 EHHm nH Am\mev.onoo ononoEHn .HKHN um omonoum oanso ooHoe omnmuo nH oomHoEEH EHHH emmuoo 902.000 non A0000 0.00 x 00 598.000 o0Hmcou cH mango .3 $25. 93 Table 41. Statistical evaluation of the change in tensile strength for SELAR ® EVOH film. Mean Difference (MD) (CD) TS(O) - TS(2.037) *0.97 i 0.73 0.44 i 0.53 TS(O) - TS(2.412) 0.31 i 0.73 0.00 i 0.53 TS(O) - TS(2.633) 0.23 i 0.73 -0.13 i 0.53 TS(O) - TS(4.310) 0.46 i 0.73 0.51 i 0.53 TS(O) - TS(6.188) 0.45 i 0.73 0.46 i 0.53 TS(O) - TS(9.261) *0.88 i 0.73 TS(2.037) - TS(2.412) -0.66 i 0.73 -0.44 i 0.53 TS(2.037) - TS(2.633) *-0.74 i 0.73 *-0.57 $0.53 TS(2.037) - TS(4.310) -0.50 i 0.73 0.07 i 0.53 TS(2.037) - TS(6.188) -0.52 i 0.73 0.02 i 0.53 TS(2.037) - TS(9.261) -0.08 i 0.73 TS(2.412) - TS(2.633) -0.08 i 0.73 -0.13 i 0.53 TS(2.412) - TS(4.310) 0.15 i 0.73 0.51 i 0.53 TS(2.412) - TS(6.188) 0.14 i 0.73 0.46 i 0.53 TS(2.412) - TS(9.261) 0.57 i 0.73 TS(2.633) - TS(4.310) 0.23 i 0.73 *0.64 i 0.53 TS(2.633) - TS(6.188) 0.22 i 0.73 *0.59 i 0.53 TS(2.633) - TS(9.261) 0.65 i 0.73 TS(4.310) - TS(6.188) -0.02 i 0.73 -0.05 i 0.53 TS(4.310) - TS(9.261) 0.42 i 0.73 TS(6.188) - TS(9.261) 0.44 i 0.73 * Significant difference at 97 percent confidence TS(O) = TS(2.037) TS(2.412) TS(2.633) TS(4.310) TS(6.188) TS(9.261) 114D: CD = me an mean value of initial value mean me an mean me an mean value value value value value Machine direction Cross machine direction containing containing containing containing containing containing 2.037 2.412 2.633 4.310 6.188 9.261 of mg/g mg/g mg/g mg/g mg/g mg/g of of of of of intervals d-limonene d-limonene d-limonene d-limonene d-limonene d-limonene 94 Table 42. Statistical evaluation of the change in tensile strength for SELAR ® Co-PET film. Mean Difference (MD) (CD) TS(O) - TS(0.003) -0.31 i 0.97 -0.86 i 1.03 TS(O) - TS(0.008) -0.23 i 0.97 -0.68 i 1.03 TS(O) - TS(0.013) -0.08 i 0.97 -0.61 i 1.03 TS(O) - TS(0.019) -0.39 i 0.97 -0.76 i 1.03 TS(O) - TS(0.019) -0.24 i 0.97 TS(O) - TS(0.025) -0.39 i 0.97 -0.89 i 1.03 TS(0.003) - TS(0.008) 0.08 i 0.97 0.19 i 1.03 TS(0.003) - TS(0.013) 0.23 i 0.97 0.25 i 1.03 TS(0.003) - TS(0.019) -0.05 i 0.97 0.10 i 1.03 TS(0.003) - TS(0.019) 0.07 i 0.97 TS(0.003) - TS(0.025) -0.08 i 0.97 -0.03 i 1.03 TS(0.008) - TS(0.013) 0.15 i 0.97 0.06 i 1.03 TS(0.008) - TS(0.019) -0.12 i 0.97 -0.09 i 1.03 TS(0.008) - TS(0.019) -0.01 i 0.97 TS(0.008) - TS(0.025) -0.16 i 0.97 -0.21 i 1.03 TS(0.013) - TS(0.019) -0.28 i 0.97 -0.15 i 1.03 TS(0.013) - TS(0.019) -0.16 i 0.97 TS(0.013) - TS(0.025) -0.30 i 0.97 -0.27 i 1.03 TS(0.019) - TS(0.019) 0.11 i 0.97 TS(0.019) - TS(0.025) -0.03 i 0.97 -0.12 i 1.03 TS(0.019) - TS(0.025) -0.14 i 0.97 * Significant difference at 97 percent confidence intervals TS(O) = TS(0.003) TS(0.008) TS(0.013) TS(0.019) TS(0.025) me an me an mean me an mean Machine direction Cross machine direction value value value value value mean value of initial containing 0.003 containing 0.008 containing 0.013 containing 0.019 containing 0.025 mg/g mg/g mg/g mglg mg/g of d-limonene of d-limonene of d-limonene of d-limonene of d-limonene 95 120 n 4.) o» n 3 'x 0’ Y x ,2 100 Y x x 0... m __ 8 T B .x o .n 4.) ,5 80 1* o ow n o . .n L) (P Q) 60 v- > 0... 4.) o H 0 D a: X Machine direction 40 1 I 1 I 1 J 1 I 1 X Cross machine direction 0 2 4 6 8 10 Limonene Conc. (mg/g) Figure 16. Relationship between tensile strength and d-limonene concentration for ALATHON ® LDPE film. 96 120 100 80 Relative % Change in the Tensile Strength 60 . A Machine direction 40 1 J .1 l . J . 1 . A Cross machine direction 0 2 4 6 8 10 Limonene Conc. (mg/g) Figure 17. Relationship between tensile strength and d-limonene concentration for SELAR ® EVOH film. 97 120 .n ‘6" 8 _ O :3 1 HP— U) A—O—r 9 o 100 O H .04 U) n o e o .n 4..) C 80 - H o ow c o .n L) “'9 60 - o > ----I .LJ 3 g 0 Machine direction 0 Cross machine 40 1 | - l - direction 0.00 0.01 0.02 0.03 Limonene Conc. (mg/g) Figure 18. Relationship between tensile strength and d-limonene concentration for SELAR ® Co-PET film. 98 43, 45 and 46. Statistical evaluation of percent elongation at break data are summarized in Tables 44, 47 and 48. The relationship between percent elongation at break and sorbed d-limonene concentration levels for the test films is presented in Figures 20 - 23, respectively. The absorption of d-limonene did not significantly affect elongation at break for the three films. (6) Heat seal strength Heat seal strength (lbs/in) values obtained for the respective test films as a function of sorbed limonene levels are presented in Tables 49, 51 and 52. The relationship between the heat seal strength and d-limonene concentration for the test films is shown in Figures 23 - 24. The results of statistical evaluation of the change in heat seal strength for the test films are presented in Tables 50, 53 and 54. Significant differences were observed for all films at the 97 percent confidence level. Impactjesistanss The impact failure weights of the control films (not immersed) and the sample films (immersed in the juice for 24 days) are shown in Table 55. Determination of impact failure weight is shown in APPENDIX VI. The relative percent change in impact failure weight of the films increased as a result of sorption of the aroma compounds (48.6 % increase). However, that of the ALATHON ® LDPE films decreased (8.4 %) . 11L. ~11“ “ii 99 noHuuouHo oanUmE moouo coHuooHHo oanooz 00 Q2 noonn no noHummnoHo w nH omnono unoonoa o>HumHon ”mHmonunouom mucoEonsmooe now no mnoHumH>oo oumonoum onm mnmoe ouo manmou one 00: A0000 A0000 2.000 A000. A000: 000 H 000 00 H 000 000 H 0.00 000 H 000 00 H 000 00 H 000 A80 A0.0000 A0.0000 A0.0000 A0.0000 A0.0000 A0.000 A0.000. . 00 H 000 00 H 000 00 H 000 0.00 H 000 00 H 000 000 H 000 00 H 000 80,: 0000028000000 00H x o0H x 00H x 00H 00 SH x 09H x 8H 00 0090001 000.0 000.0 000.0 000.0 000.0 000.0 000.0 EHHm nH Am\mev.onoo ononoeHH .UmHN um omououm manso ooHsn omnouo nH oomnoeeH EHHH 0000 ovzomeaqn non A00 xmonn 00 co00moco0o unmonom .00 o0nme 100 Table 44. Statistical evaluation of the change in elongation at break for ALATHON ®>1DPE film. Mean Difference (MD) (CD) ST(O) - ST(0.143) 45.8 i 121.8 37.9 1 134.3 ST(O) - ST(0.281) -82.9 i 121.8 40.4 1 134.3 ST(O) - ST(0.474) -41.3 1 121.8 *169.5 i 134.3 ST(O) - ST(1.461) -25.7 i 121.8 —16.0 i 134.3 ST(O) - ST(3.046) -65.8 i 121.8 56.4 1 134.3 ST(O) - ST(5.203) -35.8 i 121.8 ST(0.143) - ST(0.281) *-128.7 i 121.8 2.1 1 134.3 ST(0.143) - ST(0.474) -87.1 i 121.8 131.6 i 134.3 ST(0.143) - ST(1.461) -71.5 i 121.8 -54.0 1 134.3 ST(0.143) — ST(3.046) -111.6 i 121.8 18.5 i 134.3 ST(0.143) - ST(5.203) -81.6 i 121.8 ST(0.281) - ST(0.474) 41.6 i 121.8 129.5 i 134.3 ST(0.281) - ST(1.461) 57.2 i 121.8 -56.1 i 134.3 ST(0.281) - ST(3.046) 17.1 i 121.8 16.4 1 134.3 ST(0.281) - ST(5.203) 47.1 i 121.8 ST(0.474) - ST(1.461) 15.6 i 121.8 *-185.6 i 134.3 ST(0.474) - ST(3.046) -24.5 i 121.8 -113.1 i 134.3 SR(0.474) - ST(5.203) 5.5 i 121.8 ST(1.461) - ST(3.046) -40.1 i 121.8 72.5 i 134.3 ST(1.461) - ST(5.203) -10.1 i 121.8 ST(3.046) - ST(5.203) 30.0 i 121.8 * Significant difference at 97 percent confidence intervals ST(O) = mean value of initial ST(0.143) = mean value containing 0.143 mg/g of d-limonene ST(0.281) = mean value containing 0.281 mg/g of d-limonene ST(0.474) = mean value containing 0.474 mg/g of d-limonene ST(1.461) = mean value containing 1.461 mg/g of d-limonene ST(3.046) = mean value containing 3.046 mg/g of d-limonene ST(5.203) = mean value containing 5.203 mg/g of d-limonene MD Machine direction CD Cross machine direction 101 DO DZ noHuooHHo oanooE omouu noHuooHHo oanooz nooun no noHuomnoHo H CH omnono unoonom o>HuoHoH ”mHmonunouom munoEonsmmoe non mo mnoHuoH>oo Unmonoum ono mnmoe ouo muHSmoH one A0000 A0000 0.0000 A0000 A0000 A000: 00 H 000 00 H 000 00 H 000 000 H 000 00 H 000 00 H 000 A80 A0.000 Ae.000 A0.000 A0.000 A0.000 A0.000 A0.0000 00 H 00.0 00 H 000 00 H 000 00 H 000 00 H 000 000 H 000 00 H 000 E0: mo>m®m¢000 00me 00me ome 00me 00me 00me ome 0000.001 000.0 000.0 000.0 000.0 000.0 000.0 000.0 EHHm nH Am\mev.onou ononoEHn .UeHN um omonoum mnHHso ooHsn oonmno nH oomHoEEH EHHH 00020 e 02.000 non A00 000300 00 080000800. usoonom .00 00080.0. 102 DU 92 n0HuoonHo oanooE mmouo noHuoonHo oanomz xooun um noHuomCOHo H CH omnono unounom o>HuoHoH umHmonunouom munoEonsmooE now no mnoHumH>oU pumonoum ono mnooe ouo muHsmou one Am.NHHv AH.e0Hv Ao.mHHv Av.mOHv Ae.HOHV Ao.OOHV 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 Aoov A0.0000 A0.0000 A0.000. A0.0000 A0.0000 A0.0000 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 0.0 H 0.0 Ans. emmlooegmw ome ome 00me ome ome 00me 00093.0: 000.0 000.0 000.0 000.0 000.0 000.0 EHHm nH Am\mev.onou ononoEHn .UoHN no omououo mnHuso ooHsfl omnmuo nH oomHoEEH EHHH 0.0018 9 02.000 .80 A00 0.0300 00 0600008000 unoonom .00 00090.0 103 Table 47. Statistical evaluation of the change in elongation at break for SELAR ®>EVOH film. Mean Difference (MD) (CD) ST(O) - ST(2.037) 35.1 i 108.8 36.6 i 105.5 ST(O) - ST(2.412) 28.4 i 108.8 *108.1 i 105.5 ST(O) - ST(2.633) 18.5 1 108.8 10.4 i 105.5 ST(O) - ST(4.310) 76.5 1 108.8 73.0 t 105.5 ST(O) - ST(6.188) 56.0 1 108.8 67.1 i 105.5 ST(O) - ST(9.261) 81.8 i 108.8 ST(2.037) - ST(2.412) -6.7 i 108.8 71.5 1 105.5 ST(2.037) - ST(2.633) -16.6 i 108.8 -47.0 i 105.5 ST(2.037) - ST(4.310) 41.4 i 108.8 36.4 i 105.5 ST(2.037) - ST(6.188) 20.9 i 108.8 30.5 i 105.5 ST(2.037) - ST(9.261) 46.7 i 108.8 ST(2.412) - ST(2.633) -9.9 1 108.8 *-118.5 i 105.5 ST(2.412) - ST(4.310) 48.1 1 108.8 -35.1 i 105.5 ST(2.412) - ST(6.188) 27.6 i 108.8 -41.0 i 105.5 ST(2.412) - ST(9.261) 53.4 i 108.8 ST(2.633) - ST(6.188) 37.5 i 108.8 77.5 i 105.5 ST(2.633) - ST(4.310) 58.0 i 108.8 83.4 i 105.5 ST(2.633) - ST(9.261) 63.3 1 108.8 ST(4.310) - ST(6.188) -20.5 1 108.8 -5.9 i 105.5 ST(4.310) - ST(9.261) 5.3 i 108.8 ST(6.188) - ST(9.261) 25.8 i 108.8 * Significant difference at 97 percent confidence intervals ST(O) = ST(2.037) ST(2.412) ST(2.633) ST(4.310) ST(6.188) ST(9.261) mean value of initial mean mean mean mean me an me an value value value value value value Machine direction Cross machine direction containing containing containing containing containing containing 2.037 2.412 2.633 4.310 6.188 9.261 mglg mglg mg/g mg/g mg/g mg/g of d-limonene of d-limonene of d-limonene of d-limonene of d-limonene of d-limonene 104 Table 48. Statistical evaluation of the change in elongation at break for SELAR ® Co-PET film. Mean Difference (MD) (CD) ST(O) - ST(0.003) -0.34 i 0.55 -0.08 i 6.02 ST(O) - ST(0.008) -0.21 i 0.55 -0.10 i 6.02 ST(O) - ST(0.013) -0.54 i 0.55 -0.48 i 6.02 ST(O) - ST(0.019) -0.19 i 0.55 -3.30 + 6.02 ST(O) - ST(0.025) -0.21 i 0.55 -0.28 i 6.02 ST(0.003) - ST(0.008) -0.01 i 0.55 -0.02 i 6.02 ST(0.003) - ST(0.013) -0.30 i 0.55 -0.40 i 6.02 ST(0.003) - ST(0.019) 0.10 i 0.55 -0.20 i 6.02 ST(0.003) - ST(0.025) -0.01 i 0.55 -0.20 i 6.02 ST(0.008) - ST(0.013) -0.33 i 0.55 -0.38 i 6.02 ST(0.008) - ST(0.019) 0.02 i 0.55 -0.10 i 6.02 ST(0.008) - ST(0.025) 0.01 i 0.55 -0.18 i 6.02 ST(0.013) - ST(0.019) 0.35 i 0.55 0.30 i 6.02 ST(0.013) - ST(0.025) 0.33 i 0.55 0.20 i 6.02 ST(0.019) - ST(0.025) -0.02;0.55 -0.10 i 6.02 * Significant difference at 97 percent confidence intervals ST(O) = mean value of initial ST(0.003) = mean value containing 0.003 mg of d-limonene ST(0.008) = mean value containing 0.008 mg of d-limonene ST(0.013) = mean value containing 0.013 mg of d-limonene ST(0.019) = mean value containing 0.019 mg of d-limonene ST(0.025) = mean value containing 0.025 mg of d-limonene MD = Machine direction CD = Cross machine direction 105 140 120 80 Relative % Change in the Elongation Percent at Break X Machine direction X Cross machine direction 60 Limonene Conc. (mg/g) Figure 19. Relationship between elongation percent at break and d—limonene concentration for ALATHON ® LDPE film. 106 +1 140 n o o H o m I n o H -g 120- 01 n 0 Fl nan o 12o r:0 Him 545 100 o ow n o .n L) 6P 80 53 or! J.) o '3 I- m A Machine direction 50 1 J 1 l J l n l 1 A Cross machine direction Limonene Conc. (mg/g) Figure 20. Relationship between elongation percent at break and d—limonene concentration for SELAR ®EVOH film. 107 g 120 o o H o m n o -H fi 100 81 n o F... m.x o a)o £1H +’m .54.; 80- o oi n m I- .n L) w m 60 - > 001 JJ o H 32 9 Machine direction 40 J I . | . 0 Cross machine direction 0.00 0.01 0.02 0.03 Limonene Conc. (mg/g) Figure 21. Relationship between elongation percent at break and d-limonene concentration for SELAR ®Co-PET film. 108 The increase in the failure weight for the SELAR ®EVOH films is probably closely related to the increased flexibility of the film, due to sorption of the aroma compound. The results of the ALATHON ® LDPE film were in agreement with the finding of Hirose, (1988), who reported 12 percent decrease in impact resistance of LDPE after being immersed in an orange juice sample. This was attributed to sorption of d-limonene, resulting in the weakening or loss of intermolecular and intromolecular non-covalent interaction between polymer chains. ‘ 109 noHuoouHo oanooE mmouu u no noHuooHHo oanomz n2 numnouum Hmom noon nH omnono unoouom o>HuoHo0 "mHmonunouom munoEouzmmoe xHo mo mnoHuoH>oo ouoonmum cam mnmoe ouo muHSmou one A0.000 A0.000 A0.000 A0.000 A0.00V A0.000. eo.o H 0m.m m0.o H mm.m mo.o H om.~ mo.o H 00.0 00.0 H mm.~ mm.o H mm.~ Anzv omo0®zome§m 00me ome ome 00me 00me 00me mafia. 000.0 000.0 000.0 000.0 000.0 000.0 EHHe nH Am\mev .onoo ononoEHH .oeHN no omonoum mnHHsU ooHse omnmno nH oomnoeeH EHHH 08.0 a zone; .80 3000000 000.900.0000 080 00oz .00 3000.0. 110 Table 50. Statistical evaluation of the change in heat seal strength for ALATHON ® LDPE film. Mean ALATHON®LDPE Difference MD HS(O) - HS(0.143) *0.37 i 0.26 HS(O) - HS(0.281) *0.55 i 0.26 HS(O) - HS(0.474) *0.46 i 0.26 HS(O) - HS(1.461) *0.66 i 0.26 HS(O) - HS(3.046) *0.42 i 0.26 HS(0.143) - HS(0.281) 0.18 i 0.26 HS(0.143) - HS(0.474) 0.09 i 0.26 HS(0.143) - HS(1.461) *0.29 i 0.26 HS(0.143) - HS(3.046) 0.04 i 0.26 HS(0.281) - HS(0.474) -0.10 i 0.26 HS(0.281) - HS(1.461) 0.11 i 0.26 HS(0.281) - HS(3.046) -0.14 i 0.26 HS(0.474) - HS(1.461) 0.21 i 0.26 HS(0.474) - HS(3.046) -0.04 i 0.26 HS(1.461) - HS(3.046) -0.25 i 0.26 * Significant difference at 97 percent confidence intervals HS(O) = mean value of initial HS(0.143) = mean value containing 0.143 mg/g of d-limonene HS(0.281) = mean value containing 0.281 mg/g of d-limonene HS(0.474) = mean value containing 0.474 mg/g of d-limonene HS(1.461) = mean value containing 1.461 mg/g of d-limonene HS(3.046) = mean value containing 3.046 mg/g of d-limonene Machine direction MD= = Cross machine direction 111 noHuoonHo oanome moono u no noHuooHHo oanooz a: numnouum Hmom noon nH omnmno unoouoa o>HuoHou "mHmonunouom munoeousmmoe no» mo mnoHumH>oo ouoonoum cam mnooe onm ouHSmoH one A0.000 A0.000 A0.000 Ae.e00 A0.000 A0.000v 00.0H00.0 00.0H00.0 00.0 H000 00.0H00.0 00.0H00.0 00.0H00.0 A0,: 550002000 00me ome ome ome ome ome 00008.0. 000.0 00.0 000.0 000.0 000.0 0 EHHe nH Am\mev.onoo ononoEHn .oon no ooououm manso ooHsn omnouo nH oomuoeeH EHHH 010900 e 02.0mm no.0 Anton: numnouum Hmom noon .3 oHnoe 112 noHuoouHo oanooe moouo u no noHuooHHo oanomz oz numnouum Hoom noon nH omnmno unoouom o>HumHou “mHmonunouom munoEoHSmooe nou Ho mnoHumH>oo ouoocmum ono mnmoe ouo muHSmoH one A0000 A008 2.00. A0000 A0000 8.003 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0, 00.0 H 00.0 00.0 H 00.0 00.0 H 00.0 A900 emouooemfimm 00me ome 00me 00me ome 00me 3008.01 000.0 000.0 000.0 000.0 000.0 000 0 EHHe nH Am\mev.onoo ononoEHH .oeHN um ommuoum mnHuso ooHse oonouo nH oomHoEEH EHHH .5018 a 90.000 08 8000000 3005.000 0000 00oz .00 0.30.0 113 Table 53. Statistical evaluation of the change in heat seal strength for SELAR ® EVOH. Mean SELAR®EVOH Difference MD HS(O) - HS(2.037) 0.15 i 0.28 HS(O) - HS(2.412) *0.32 i 0.28 HS(O) - HS(2.633) 0.18 i 0.28 HS(O) - HS(4.310) *0.31 i 0.28 HS(O) - HS(6.188) 0.07 i 0.28 HS(2.037) - HS(2.412) 0.17 i 0.28 HS(2.037) — HS(2.633) 0.03 i 0.28 HS(2.037) — HS(4.310) 0.15 i 0.28 HS(2.037) - HS(6.188) -0.09 i 0.28 HS(2.412) - HS(2.633) -0.14 i 0.28 HS(2.412) - HS(4.310) -0.02 i 0.28 HS(2.412) - HS(6.188) -0.25 i 0.28 HS(2.633) - HS(4.310) 0.13 i 0.28 HS(2.633) - HS(6.188) -0.11 i 0.28 ‘HS(4.310) - HS(6.188) -0.24 i 0.28 * Significant difference at 97 percent confidence intervals HS(O) = mean value of initial HS(2.037) = mean value containing 2.037 mg/g of d-limonene HS(2.412) = mean value containing 2.412 mg/g of d-limonene HS(2.633) = mean value containing 2.633 mg/g of d-limonene HS(4.310) = mean value containing 4.310 mg/g of d-limonene HS(6.188) = mean value containing 6.188 mg/g of d-limonene MD Machine direction CD Cross machine direction 114 Table 54. Statistical evaluation of the change in heat seal strength for SELAR ® Co-PET film. Mean SELAR®Co-PE Difference MD HS(O) - HS(0.003) 1.45 i 2.05 HS(O) - HS(0.008) *2.42 i 2.05 HS(O) - HS(0.013) *2.40 i 2.05 HS(O) - HS(0.019) 1.39 i 2.05 HS(O) - HS(0.025) *2.43 i 2.05 HS(0.003) - HS(0.008) 0.97 i 2.05 HS(0.003) - HS(0.013) 0.95 i 2.05 HS(0.003) - HS(0.019) -0.06 i 2.05 HS(0.003) - HS(0.025) 0.99 i 2.05 HS(0.008) - HS(0.013) -0.02 i 2.05 HS(0.008) - HS(0.019) -1.03 i 2.05 HS(0.008) - HS(0.025) 0.01 i 2.05 HS(0.013) - HS(0.019) -1.01 i 2.05 HS(0.013) - HS(0.025) 0.04 i 2.05 HS(0.019) - HS(0.025) 1.04 i 2.05‘ * Significant difference at 97 percent confidence intervals HS(O) = mean value of initial HS(0.003) = mean value containing 0.003 mg/g of d-limonene HS(0.008) = mean value containing 0.008 mg/g of d-limonene HS(0.013) = mean value containing 0.013 mg/g of d-limonene HS(0.019) = mean value containing 0.019 mg/g of d-limonene HS(0.025) = mean value containing 0.025 mg/g of d-limonene MD Machine direction CD = Cross machine direction 115 120 .C: a C: a, P H 4J U) 73 100 (I) U) 4.) (U (I) a: (D ,c: 0 80 C: H 0) Cl C: o .C‘. U 0 60 .. g ALATHON ® 33' _ LDPE(MD) 3 o g ‘ SELAR 4O 1 I 1 I 1 I 1 I 1 EVOH(MD) Limonene Conc. (mg/g) Figure 22. Relationship between hear seal strength and d- limonene concentration for ALATHON ® LDPE and SELAR ® EVOH film. 116 f1 0 120 C. 0) H .|.J U) r-( (‘0 Q) "’ 100 4.) (0 Q) a: Q) .C: 4..) C "i 80 (D O‘ C.‘ (U 5 *- 6P 9 60.. H 4.) (U r-l (D m b SELAR® 40 1 I 1 I 1 . CO-PET(MD) 0.00 0.01 0.02 0.03 Limonene Conc. (mg/g) Figure 23. Relationship between heat seal strength and d-limonene concentration for SELAR ®Co-PET film. 117 Table 55. Influence of sorption on impact resistance of the sample films. Thickness Limonene Conc. Impact failure weight Sample (mil) (mg/9) (g) (%) ALATHON® 1.65 0.0 109.5 100.0 -LDPE (41.9 um) 5.2 100.3 91.6 SELAR® 0.83 0.0 66.4 100.0 -EVOH (21.1 um) 9.3 98.7 148.6 SELAR® 2.65 0.0 42.7 100.0 -Co-PET (67.3 um) 0.03 48.9 114.5 118 24 m H m I - 0 0 5 200- 150' 100' uanoz oHDHHom HommEH onu nH omnmno w o>HumHom Storage Time (days) Change in impact failure weight of the test films. Figure 24. CONCEUSION These studies were designed to investigate the sorption of organic volatile compounds by plastic films, and to evaluate the influence of the sorption of these compounds on the mechanical properties of the plastic films as a function of sorbed concentration levels. The film tested included ALATHON ® LDPE, SELAR ® EVOH and SELAR ® Co-PET. The amount of d—limonene sorbed by the test films was determined as a function of storage time and was found to vary with the specific polymer structure. The sorption by SELAR ® Co- PET film was significantly lower in comparison to that of the other two films. Absorption of d-limonene by the plastic films occurred within 1 day after immersion in orange juice. After 3 days, the rate of absorption by ALATHON 3’ LDPE and SELAR ®EVOH plateaued and soon reached equilibrium, while for SELAR ® Co- PET, a slow increase was observed for 24 days. The sorption of d-limonene by the test films was found to affect the (a) modulus of elasticity (SELAR ‘9 EVOH, SELAR ® Co- PET), (b) yield stress (SELAR ®EVOH), (c) stress at 100 % elongation (ALATHON ® LDPE, SELAR ® EVOH), (d) heat seal strength (ALATHON ® LDPE), and (e) impact resistance (SELAR ® EVOH, ALATHON ® LDPE) . Sorption of d-limonene influenced the modulus of elasticity, yield stress and stress at 100 percent 119 *i 120 elongation for SELAR ® EVOH film. These properties are closely related to stiffness or flexibility of plastics. In this case, the sorbent probably acted as a plasticizer. Consequently, SELAR ® Co- PET would be better than ALATHON ® LDPE and SELAR ® EVOH as a contact layer for orange juice, as regards sorption of organics. More detailed experiments concerning this phenomenon are proposed in order to determine the level of sorption of volatile flavor compounds by plastic films of differing molecular structure. APPENDICES APPENDIX I STANDARD CALIBRATION Four standard calibration factors were employed, depending on the gas chromatograph (GC) models used and probe compounds, namely, d-limonene, neral and geranial. Table 56: This standard was used for determination of d— limonene concentrations in the orange juice and extracted by the solvent, utilizing H.P. GC Model #5830 equipped with a packed column: d-limonene standard calibration factor = 1.457 x 10'12 (g/a.u.) Table 57: This standard was used for determination of d- limonene concentrations extracted by the solvent, utilizing H.P. GC Model #5890 equipped with a capillary column: d-limonene standard calibration factor = 0.140 x 10"12 (g/a.u.) Table 58: This standard was used for determination of neral concentrations extracted by the solvent, utilizing H.P. GC Model #5890 equipped with the capillary column: Neral standard calibration factor = 0.953 x 10-12 (g/a.u.) Table 58: This standard was used for determination of geranial concentrations extracted by the solvent, utilizing H.P. GC Model #5890 equipped with the capillary column: Geranial standard calibration factor = 0.992 x 10‘12 (g/a.u.) 121 122 Table 56. Limonene Standard Calibration Curve Data: G.C. Model #5830 equipped with the packed column. AREA RESPONSE ABSOLUTE QUANTITY ( * 10 A---9 gms) (X - axis) (Y - axis) 0 0.0 33550 50.4 69660 100.8 142500 201.6 275400 403.2 123 y = - 0.6922 + 1.4574x R = 1.00 500 450 »~ 400 TE 0 350 (I ”*1 O H 300 f, E 250 H E-I E 200 D O a 150 D 8 a 100 50 O A I 1 I 1 I 1 l 1 l 1 O 50 100 150 200 250 300 AREA RESPONSE (*1023) Figure 25. D-limonene standard calibration curve: packed column (G.C. Model #5830) 124 Table 57. Limonene Calibration Curve Data: G.C. Model #5890 equipped with the capillary column. AREA.RESPONSE. .ABSOLUTE QUANTITY ( * 10 A-9 gms) (X - axis) (Y - axis) 0 0.0 421220 50.4 842200 100.8 1416730 201.6 2922300 403.2 125 y = — 5.8966 + 0.1402x R = 1.00 500 ’0 400- E. O m I I < ~._ 0 E 300- >4 B . H {-1 E 200- O Li! a . :3 14 O a 100.- 0 1 l 1 J 1 I 1 l 1 I 1 0 500 1000 1500 2000 2500 3000 AREA RESPONSE (*1093) Figure 26. D-limonene standard calibration curve: capillary column (G.C. Model #5890) 126 y = 40.3406 + 10.3639x R = 1.00 3000 2500 - c’n‘ ( I- O H 5, 2000 - O m . co :2 1500 - :g + Z O m U) glooo- i 500 - o 11.111.1111 0 50 100 150 200 250 300 AREA RASPONSE #5830 (*1023) Figure 27. Relationship of the area responses of d-limonene (G.C. Model #5830 vs. #5890) 1 :i 127 Table 58. Neral and Geranial Standard Calibration Curve Data: G.C. Model #5890 equipped with capillary column. Neral AREA RESPONSE (X - axis) ABSOLUTE QUANTITY (Y - axis) ( * 10 “-12 gms) 0 0.0 1666 890.0 4236 1780.0 13751 3550.0 Geranial AREA RESPONSE (X - axis) ABSOLUTE QUANTITY (Y - axis) ( * 10 “-12 gms) 0 0.0 1883 355.2 7261 2220.0 13468 4440.0 31649 8880.0 128 y = 371.5397 + 0.2409x R = 0.98 4000 . A 3500 - 13 g‘ . 6‘ 3000 0 (I 1. O ‘1'? 2500 .. >4 :- S g 2000 - :5 - El 0' 1500 - m e D . a 500 - OH 1 l 4 J 1 I 1 0 5000 10000 15000 20000 AREA RESPONSE Figure 28. Neral standard calibration curve: capollary column (G.C. Model # 5890) 129 y = 90.3421 + 0.2846x R = 1.00 10000 9000 8000 7000 6000 5000 4000 3000 2000 ABSOLUTE QUANTITY (*1OA-12 Gms) 1000 0. 1 I 1 I 1 I 1 0 10000 20000 30000 40000 AREA RESPONSE Figure 29. Geranial standard calibration curve: capillary column (G.C. Model #5890) APPENDIX H The Components of the Preservatives Antioxidant (a) SUSTANE W (UOP INC.) Ingredients (wt percent) (1) (2) (3) (4) (5) (6) (7) mono-tertiary-butyl-r-hydroxy anisole (BHA) (10) 2, 6-di-tert—butyl-para-cresol (BHT) (10) n-propy1—3,4,5-trihydroxy benzoate (PG) (6) citric acid (6) propylene glycol (8) edible oil (28) mono and diglycerides of fatty acids (32) (b) SUSTANE 20 A (UOP Inc.) Ingredients (wt percent) (1) (2) (3) (4) (5) tertiary-butyl hydroquinone (TBHQ) (20) citric acid (3) propylene glycol (15) edible oil (30) mono and diglycerides of fatty acids (20) 0.02 percent (w/w) (a) + (b) was added to the orange juice at the beginning of storage. 130 131 E !' . 1. J E I (c) Sodium azide (Sigma Chemical Co.) 0.02 percent (w/w) (c) was added to the juice at the beginning of storage. ‘40. APPENDIX III The Sample Correlation Coefficient The purpose of this analysis was to determine a correlation between the different analytical methods used to determine concentrations of limonene. Variables considered were the different solvents used for extraction, the G.C. techniques using packed and capillary column analysis and the two analytical methods, namely, the titration method and the gas chromatographic procedure. One simple kind of association between the variables X and Y produces pairs of values or, graphically, points that scatter about a straight line. A small amount of scatter about a line indicates strong association; a large amount of scatter is a manifestation of weak association. A numerical measure of this relationship is called the sample correlation coefficient. The sample correlation coefficient R is given by: Sample correlation coefficient Zcxi-YXYi-‘n 1=1 2005502 2.00-W i=1 1:1 (9) where (X1, Y1),..-,(Xn, Yn) are the n pairs of observations. (Bhattacharyya, 1977.) 132 APPENDIX IV I E I-]' i fxam EIEIHQN 9 112213 (BIIAIHQN Q 1545) Eilm Objective: To establish the desorption ratie of limonene from the ALATHON ® LDPE film occurs very rapidly. Method: Two sheets of 5" x 4" ALATHON ® LDPE film (258.1 cm2) were placed in a brown glass bottle with 260 ml of the orange juice. The bottles were kept for 6 days in the dark at 21°C. The films were removed from the bottles and rinsed with water for one minute. The films were then left for predetermined times of 0, 10, 30, 60 minutes and 1 day, at room temperature. After each time period, the films were cut into 1 cm x 1 cm strips, and placed into 30 ml septa seal vials with 25 ml of solvent (ethyl acetate) and then sealed with silicone coated septa and tear away seals. Because the rinsing and the cutting process took approximately five minutes, the films were left for 5, 15, 35, 65 and 1440 minutes totally. After extraction of the film by ethyl acetate for one day, 1 ul of the solution was sampled and injected directly into the G.C. The concentrations of d-limonene were determined using the calibration curves (APPENDIX D 133 134 Results: Rapid desorption of d-limonene from the ALATHON ®LDPE film into the environment was found. The extent of d- limonene loss from the ALATHON ® LDPE film as a result of desorption is presented in Table 59. The d-limonene concentration in the ALATHON ® LDPE is shown in Figure 29. Desorption loss of geranial from the ALATHON ®LDPE film into the environment was observed as well. Desorption of geranial from the ALATHON ® LDPE film is presented in Table 58, and geranial concentration as a function of time is shown in Figure 30. 135 Table 59. Desorption of d-Limonene and Geranial from ALATHON ® LDPE film. Exposure d-limonene Conc. (mglg) Geranial (mglg) Time Packed Column Capillary Column Capillary Column (min.) Analysis (a) Analysis (b) Analysis (b) X i s.d. X i s.d. X i s.d. 5 9.510 0.100 11.288 3.510 0.074 0.011 15 5.379 0.821 5.754 1.773 0.084 0.025 35 1.081 0.366 1.053 0.175 0.061 0.004 65 0.125 0.029 0.170 0.054 1440 0.000 0.000 0.000 (a) H.P.#5830 equipped with packed column (b) H.P.#5890 equipped with capillary column X i s.d. Mean and standard deviation of duplicate runs 136 y = 15.0379 * lO“(-0.0317x) R = 0.99 100 . ’0“ .1 \ 2‘ 0. 10': d . c: a O u U a) d c I (D C O .5 1: T : '9 1 '1 ' 1 1 I ' l 0 20 40 60 80 Environment Exposure Time (min.) Figure 30. D-limonene concentration as a function of the tim The film was exposed to the environment prior to analysis. 137 I y = 0.0807 * 10“(-0.0028X) R = 0.65 h l L 3 \ 2‘ V 01- B geranial 7i;/F .01 . 1 1 1 . l . 0 20 40 60 80 Environment Exposure Time (min.) Figure 31. Geranial concentration as a function of the time. The film was exposed to the environment prior to analysis. APPENDIX'V One-Way Analysis of Variance The purpose of this analysis was to determine significance of sorption on mechanical properties of each sample film. Data from the mechanical properties analysis of each film were analyzed using analysis of variance (Table 50) (ANOVA Table, Bhattacharyya, 1977). Population model for comparing k treatments Yij = u + Bj + eij, i = 1,..., nj, j = l,..., k (10) where u = overall mean Bj = the jth treatment effect, i Bj = 0 i=1 and eij are all independently distributed as N(0,S). The null hypothesis that no difference exists among the k population means can now be phrased Ho: Bl = 32 = ... = Bk = O Reject Ho if Treatment SS/(k-l) . > F k-l -k Residual SS/(n-k) a( ,n ) (11) 138 139 Table 60. ANOVA table for comparing k treatment. Source Sum of Squares d.f. Mean Square __ _. SST Treatments SST = nj(yj- y)2 k-l MST = k 1 j-l n Error SSE = 2 :(Y1j- ;)2 2 nj - k MSE = SSE j-l i-l j-l Ilj -' k j-l TCNZal. IE: 121(j’1j- 3;)2 IE: Ilj " 1 j-l i=1 j-l 140 where n = : nj j-l and Fa(k-1,n—k) is the upper 01 point of the F distribution with d.f.= (k-1,n-k). Multiple-t Confidence Intervals A set of 100(l-a)% simultaneous confidence intervals for m number of pairwise differences (uj - flj') is given by -' '— 1 (Y ' Y I) i t m S V- + '— j j a/2 n3 nd' (12) where s = {MSE} m = the number of confidence statements, and ta/Zm = the upper 012m point of t with d.f.=n-k. Using this procedure, the probability of all the m statements being correct is at least (l-a). For example, todZm for 97 percent simultaneous confidence intervals for the modulus of elasticity of ALATHON ® HDPE film are t0.03/2 * 15 = t0.0010 (MD) t0.03/2 * 10 = t0.0015 (CD) tabulated values of t with d.f. = 30 (MD) and d.f. = 24 (CD) are 3.2546 (MD) and 3.2667 (CD). 141 Table 61. ANOVA table for modulus of elasticity. ALATHON ® LDPE on» Sourse Sum of Squares d.f. Mean Square F - test TR 0.1464 5 0.02928 2.57 E 0.3419 30 0.01139 Total 0.4883 35 (CD) Sourse Sum of Squares d.f. Mean Square F - test TR 0.5154 4 0.1289 7.53 E 0.4110 24 0.01710 Total 0.9264 28 SELAR ® EVOH on» Sourse Sum of Squares d.f. Mean Square F — test TR 16.84 5 3.367 18.04 E 5.227 28 0.1867 Total 22.06 33 «In Sourse Sum of Squares d.f. Mean Square F - test TR 9.042 4 2.261 24.45 E 2.312 25 0.09460 Total 11.35 29 SELAR ® Co-PET (MD) Sourse Sum of Squares d.f. Mean Square F - test TR 162.0 5 32.41 19.49 E 42.23 26 1.663 Total 205.3 31 (CD) Sourse Sum of Squares d.f. Mean Square F - test TR 19.42 4 4.856 18.37 E 5.814 22 0.2643 Total 25.24 26 142 Table 62. ANOVA table for yield stress. ALATHON ® LDPE (NEH Sourse Sum of Squares d.f. Mean Square F - test TR 0.5123 6 0.08538 4.58 E 1.174 63 0.01863 Total 1.686 69 «in Sourse Sum of Squares d.f. Mean Square F - test TR 0.2929 5 0.05859 4.20 E 0.7528 54 0.01394 Total 1.046 59 SELAR ® EVOH on» Sourse Sum of Squares d.f. Mean Square F - test TR 6.471 6 1.079 20.17 E 3.369 63 0.05347 Total 9.840 69 (CD) Sourse Sum of Squares d.f. Mean Square F - test TR 1.399 5 0.2798 12.97 E 1.165 54 0.02158 Total 2.565 59 143 Table 63. ANOVA table for stress at 100 percent elongation. ALATHON ®fiIIJDPE (MD) Sourse Sum of Squares d.f. Mean Square F — test TR 0.09894 2 0.04947 2.75 E 0.4852 27 0.01797 Total 0.5841 29 (CD) Sourse Sum of Squares d.f. Mean Square F - test TR 0.2073 1 0.2073 14.95 E 0.2495 18 0.01368 Total 0.4568 19 SELAR ® EVOH (MD) Sourse Sum of Squares d.f. Mean Square F - test TR 3.535 2 1.767 27.96 E 1.707 27 0.06321 Total 5.241 29 (CD) Sourse Sum of Squares d.f. Mean Square F - test TR 0.6502 1 0.6502 113.62 E 0.1030 18 0.005722 Total 0.7532 19 144 Table 64. ANOVA table for tensile strength. ALATHON ® LDPE on» Sourse Sum of Squares d.f. .Mean Square - test TR 0.7887 6 0.1315 1.91 E 4.347 63 0.0690 Total 5.136 69 (CD) Sourse Sum of Squares d.f. Mean Square - test TR 1.066 5 0.2132 5.35 E 2.153 54 0.03987 Total 3.219 59 SELAR ® EVOH (NED Sourse Sum of Squares d.f. Mean Square - test TR 7.216 6 1.203 5.16 E 14.70 63 0.2333 Total 21.92 69 (CD) Sourse Sum of Squares d.f. Mean Square - test TR 4.077 5 0.8153 6.23 E 7.073 54 0.1310 Total 11.15 59 SELAR ® Co-PET on» Sourse Sum of Squares d.f. .Mean Square - test TR 1.144 6 0.1906 0.46 E 26.16 62 0.4152 Total 27.30 69 (CD) Sourse Sum of Squares d.f. Mean Square - test TR 2.544 5 0.5088 1.02 E 26.99 54 0.4999 Total 59 29.54 ‘0! 145 Table 65. ANOVA table for elongation percent at break. ALATHON ® LDPE (MD) Sourse Sum of Squares d.f. Mean Square - test TR 1090 6 181.7 2.76 E 4148 63 65.80 Total 5238 69 (CD) Sourse Sum of Squares d.f. Mean Square - test TR 2141 5 428.2 5.03 E 4598 54 85.09 Total 6739 59 SELAR ® EVOH an» Sourse Sum.of Squares d.f. Mean Square - test TR 551.8 6 91.97 1.75 E 3309 63 52.52 Total 3861 69 (CD) Sourse Sum of Squares d.f. Mean Square - test TR 1042 5 208.3 3.97 E 2834 54 52.48 Total 3875 59 SELAR ® Co-PET on» Sourse Sum of'Sqmares d.f. Mean Square - test TR 0.08937 6 0.01490 10.99 E 0.08540 63 0.01356 Total 0.1748 69 (CD) Sourse Sum of Squares d.f Mean Square - test TR 0.8066 5 0.1613 0.94 E 9.200 54 0.1712 Total 10.10 59 146 Table 66. ANOVA table for heat seal strength. ALATHON ® LDPE (MD) Sourse Sum of Squares d.f. Mean Square F - test TR 2.554 5 0.5110 15.75 E 1.752 54 0.0320 Total 4.307 59 SELAR ® EVOH (MD) Sourse Sum of Squares d.f. Mean Square F - test TR 0.8120 5 0.1620 4.23 E 2.072 54 0.0380 Total 2.884 59 SELAR ® Co-PET (MD) Sourse Sum of Squares d.f. Mean Square F - test TR 58.95 5 11.79 5.94 E 107.3 54 1.986 Total 166.2 59 APPENDIX Vq DETERMINATION OF DART IMPACT FAILURE WEIGHT Determination of dart impact failure weight of ALATHON ®’ LDPE, SELAR ® EVOH and SELAR ® Co- PET films is shown in Table 67 - 69. The impact failure weight Wf was calculated using the equation (5). 147 148 0. 0.. 0.04.... s ES 00.0m noHoEoHo coon Hump a 00.0 000000 mono 00no0n0onoo 0000 mousHHom mononoU 7 ousHHmmnnon mononoo o "ouoz 0 0.00 0 0 0 0 0 0 0 0 v 0 00.00 00. 00070 000720 0 0 0 v 0.000 umMHwEH j v.mH m.m0H "3< "03 m H 4 OH H 2 o o o o Hém 0 0 0 v o o o 7 v v. v o 0.000 0 0 0 A. A. v A, A0000 HOHUCOU HGHH H H: 060 006003 0000002 .2000 0000.0 e 290000.000 0o 0000003 000.0000 000000 .00 00000.0 149 as 00.00 0000E00o 0000 0000 s 00.0 00000: 0000 00000000000 0000 mousHHou mouonoo 7 onsHHouanon mononoo o “ouoz .mflnwmllufllHuquge v.mH H.vm "3Q "03 00.0 0002 o o 0 001.00 000 0000. 0000.00.00 m H m 7 7 7 o 7 7 7 m.m0H N N H 7 m.vNH nomHoEEH IuiHmHIIMHIHuammw v.mH m.mw u 3< n 03 DH“ OHHZ o 0 o 0 0.0.0 o o v 7 7 o o o o o 7 7.m.mm m H m 7 7 7 o 7 7 e.me N N H 7 H.vm Honunoo HnrH H H: Hme HnUHoz oHHmmHz .500 0820 e 02.000 00 0000003 00000000 0000.00 .00 00000.0. 150 as 00.0m “mumsmflu 00mg puma e mm.0 uaofimn noun "mcoHqucoo umma mmnsHHmu mmuocmv 7 musHHmmncoc mmuocmu 0 "muoz udwwum, n “aqua: m.ON >.Nv "3Q "03 m u fl OH H z 0 0 N. 0 0 . 0 0 0 0 0 0 0 0 0 0 0.~0 000 000 00000030 UmmumEEH j 0.0N >.N¢ "3Q "03 m n d OH H z o o m 00007 0 07 0 0777 0 0>.Nv m H m 0 0 0 0 0 0 0.3 Houucoo E: H H: 3% Em @3me .53 Em -8 ® .245 no £033 8303 8&5 .00 30.2. 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