DENSKW SOETWG 0F GREEN STOCK FEELING CUCUfi'fiEES F03 figlh’fi STGCK QUéLETY m RELETEB SWBIES @5921: for “so Degree of M. S. EJECBEGAN STATE UMVERSHY Daie Earnest Marshall I975 JH ESIS h- mm 5" LIBRARY ' Michigan Stab: Umversity ._..—...._ m. -M " ABSTRACT DENSITY SORTING OF GREEN STOCK PICKLING CUCUMBERS FOR BRINE STOCK QUALITY AND RELATED STUDIES By Dale Earnest Marshall Michigan leads the nation in the production of cucumbers (Cucumis sativus L.) grown for processing. An increasing problem in recent years has been losses due to bloater formation in brined cucumbers, estimated to be over $5 million annually. Balloon bloater formation has been correlated with green stock carpel separation but never with green stock density. Preliminary findings in 1971 that balloon bloater formation was inversely related to green stock density were verified in 1972 and 1973. A static flotation mech- anical separator was used to sort the cucumbers to a ratio of about 20% sinkers (more dense) and 80% floaters (less dense). Density-sorting significantly reduced (.05 level) balloon bloater formation in the sinkers compared to the floaters. In general, lens bloater formation was slightly greater in the sinkers. Total bloater formation was less in sinkers compared the the floaters. Balloon bloater formation in 1-7/16 to 1-9/16 in. diameter fruit was significantly less than in 1-9/16 to 1—7/8 in. Dale Earnest Marshall diameter fruit. 16:74 During +946-experiments, the specific gravity of 65 experimental and named varieties were measured. Variety averages varied from .9822 to .9582 (a range of .0240). Any variety whose specific gravity was .0087 different from another variety was significantly different (.01 level). Average specific gravity of the carpel region was .030 to .040 higher than in the wall region. Reducing sugar content was not related to cucumber specific gravity but was significantly different for three harvests from the same plots. The density-sorting method used had a low capacity. The specific gravity of ethanol-water sorting solutions was affected by evaporation and dilution and required alteration with different size grades, truck loads or varieties. Cucumbers have to be size graded prior to density-sorting. Investigations have shown that sorting pickling cucumbers into more dense sinkers and less dense floaters is effective in reducing balloon and total bloater formation in the sinkers. However, at present several actual or potential limitations with the ethanol-water flotation separation method have been experienced or are discussed. APPROVED: [g A m Major Professor Department Chairman DENSITY SORTING OF GREEN STOCK PICKLING CUCUMBERS FOR BRINE STOCK QUALITY AND RELATED STUDIES BY Dale Earnest Marshall A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Agricultural Engineering 1975 ACKNOWLEDGMENTS The author wishes to express sincere thanks to Dr. D. R. Heldman, Professor, Departments of Agricultural Engineering and Food Science and Human Nutrition, for his advice and direction throughout this research. My warmest thanks to J. H. Levin, ARS, USDA Research Leader, for his direction, encouragement, patience, support and his unique method of leadership in conducting practical and useful research. - My thanks to Dr. L. R. Baker, Associate Professor, Department of Horticulture, for his advice, sample evaluation, and for providing the many samples from his variety trial plots without which much of this study would not have been possible. My thanks to Dr. C. L. Bedford, Professor, Department of Food Science and Human Nutrition, for the brining of samples, evaluation of samples, and for providing research facilities. My thanks to R. J. Wolthuis, ARS, USDA Mechanical Engineering Technician, for his assistance in equipment construction, data collection and unfailing help in "getting the job done." ii My sincere thanks goes to the many students who over the years of this study aided in equipment construction, data collection, data analyses and date presentation. My sincerest appreciation to Pickle Packers Inter- national, Mr. W. R. Moore, Jr., Executive Vice President; The Industry Ad Hoc Committee for Pickling Cucumber Research at Michigan State University, Chairman, Mr. William Temple; Vlasic Food Products Co., Mr. Jack Hobson; Aunt Jane's Foods, Mr. Robert Hasso; Dailey Pickle Co., Mr. Roger Anderson; M. A. Gedney Co., formerly with Green Bay Foods Co.; Mr. Carl Landis, H. J. Heinz Co.; Mr. C. Richard Walker, Hirsch Bros. of Michigan; Aunt Jane's Foods, Div. of Borden, Inc.; H. J. Heinz Co.; and Lewis and Bernie Wilde, Wilde Manufacturing, Inc., for their encouragement, cooperation and financial assistance throughout this study. My sincere thanks to Mrs. Judy Powell and to my wife Pat for typing the rough drafts of this manuscript. For typing the final manuscript the author is indebted to Sandy Clark. My thanks to my parents who through their example instilled in me a love for agriculture. Finally, to my family, my loving thanks to my wife Pat, daughter Brenda, and son Todd for their sacrifice, continued faith, support and understanding throughout the duration of this study. iii TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES LIST OF SYMBOLS, ABBREVIATIONS, AND NOMENCLATURE CHAPTER I. INTRODUCTION Michigan and United States Cucumber Production Statistics . . . . . . . United States Losses due to Bloater Formation Evaluation for Internal Voids Preliminary Experiment -- 1971 Objectives CHAPTER II. REVIEW OF LITERATURE Specific Gravity Separation Vegetables Fruits Oil crops Equipment Methods of Measuring Density and Specific Gravity . Archimedes' principle Pycnometer method Hydrometer method CHAPTER III. PROCEDURES Size Grading Density Determination Methods Used Pycnometer Hydrometer iv m-‘inNH ooooxlmm 10 12 13 15 15 17 17 18 Laboratory Scale Experiments . . . . . Relationship of specific gravity to diameter (1972) Relationship of sample location within a fruit to specific gravity (1972) Relationship of multi-pick harvest dates and variety to specific gravity (1972) Relationship of variety to specific gravity (1973, 1974) . . Relationship of carpel strength and harves date to specific gravity (1972, 1973) Relationship of specific gravity, diameter and harvest number to sugar content (1972) Relationship of brine stock firmness to specific gravity (1973) Brining of samples Brine stock evaluation Commercial Prototype Density Sorting Detailed investigations (1972) Detailed investigation (1973) Determination of sorting solution specific gravity Density-sorting equipment Brining Brine stock evaluation CHAPTER IV. RESULTS AND DISCUSSION Laboratory Scale Experiments Relationship of specific gravity to diameter (1972) . . . . Relationship of sample location within a fruit to specific gravity (1972) Relationship of multi-pick harvest dates and variety to specific gravity (1972) Harvest dates Variety Relationship of variety to specific gravity (1973, 1974) V t 22 23 24 24 25 25 25 26 29 30 3O 31 31 31 34 39 39 39 41 Page Relationship of carpel strength and harvest dates to specific gravity (1972, 1973) . . . . . 46 Carpel strength - 1972 . . . . 46 Harvest dates - 1972 . . . . . 47 Carpel strength - 1973 . . . . 48 Relationship of specific gravity, harvest date, and diameter to sugar content (1972) 48 Harvest date . . . . . . . 54 Diameter . . . . . . . . 54 Relationship of brine stock firmness to specific gravity (1973) . . . . . 54 Frequency distribution (1972, 1973) . . 59 Relationship of bloater formation to specific gravity (1972) . . . . . 59 'Heinz 19' . . . . . . . 59 'Earli Pik' . . . . . . . 65 Relationship of bloater formation to specific gravity (1973) . . . . . 66 Precentage-of—sample-that-sink curve and bloater formation curves (1972, 1972) . 66 Commercial Prototype Density-Sorting - - 72 Bloater formation (1972) . . . . 72 'Heinz 19' . . . . . . . 72 'Earli Pik' . . . . . . . 74 Bloater formation (1973) . . . . 75 General discussion . . . . . . 77 Feasibility of density-sorting cucumbers with an ethanol-water solution . . . 81 CHAPTER V. CONCLUSIONS . . . . . . . 84 CHAPTER VI. SUGGESTIONS FOR FUTURE WORK . . . 89 BIBLIOGRAPHY . . . . . . . . . . 90 APPENDICES . . . . . . . . . . 96 Appendix Al. Acreage, yield, production, value and mechanical harvest percentage for cucumbers for pickles in Michigan, 1918-1974 . . . 96 vi Page Appendix A2. Acreage, consumption, yield and production of cucumbers for pickles for the United States, 1918-1974 . . . . . . 98 Appendix A3. Calculations of annual loss due to bloater formation in the United States . . . 99 Appendix A4. Cucumber density-sorting infor- mation sheet describing technique, equipment, sorting procedure, data sheet and hydrometer reading chart . . . . . . . . . 100 BIOGRAPHY . . . . . . . . . . . 102 vii LIST OF TABLES Regression line coefficients of the relation- ship of specific gravity to outside diameter for three varieties (1972) Relationship of multi-pick harvest dates and variety to specific gravity. Second and third harvest samples are from same plots as for first harvest (1.5 to 2.0 in. diameter) (1973) Relationship of cucumber variety to sample mean specific gravity (1.5 to 2.0 in. diameter) (1972) Relationship of cucumber variety to sample mean specific gravity (1.5 to 2.0 in. diameter) (1974) Varietal differences for green stock carpel separation and subsequent balloon bloating of brine stock; based on two replicates, 30-ga1 tanks, yeast inoculated (1.5 to 2.0 in. diameter) Baker et al. (1973) Relationship of harvest dates and carpel phenotype to sample mean specific gravity (1.5 to 2.0 in. diameter) (1972) Mean carpel strength, bloater formation, mean specific gravity, and linear regression coefficients of best-fit lines of carpel strength versus fluid specific gravity group in Figs. 6 through 13 (1.5 in. to 2.0 in. diameter) (1973) . . . . . . Mean reducing sugar content (percentage) of l cucumber variety lots (10 different varieties for three harvest dates from the same vines (1.5 to 2.0 in. diameter cucumbers) (1972) viii 33 4O 42 43 45 47 53 1 ) Table Page 9 Mean reducing sugar content (percentage) of 11 variety lots (10 varieties) presented in Table 8 as related to diameter for three harvest dates (1972) . . . . . . 56 10 Correlation coefficients of the relationship between bloater formation and specific gravity of pickling cucumbers (1972, 1973) . 65 ix Figure 6-13 14 15-16 17-18 19-20 21-22 LIST OF FIGURES Page Method used to measure cucumber diameter . 16 Percentage of green stock cucumbers that sink in a solution of a given specific gravity . . . . . . . . . 28 Side view of experimental tank used to sort green stock pickling cucumbers according to density into floaters and sinkers . . . 30 Relationship of specific gravity to outside diameter of 'Pioneer' variety cucumbers . 32 Average specific gravity of whole and various portions of pickling cucumbers. Numbers within parentheses indicate number of cucumbers in sample. One standard deviation is shown for two varieties (1.5 to 2.0 in. diameter) . . . . . . 35 Carpel strength measurements of green stock cucumbers sorted into fluid specific gravity groups . . . . . . . . . . 49-52 Firmness of brined cucumbers that were density-sorted as green stock into fluid specific gravity groups. Numbers within parentheses indicate number of cucumbers in sample (1.5 to 2.0 in. diameter) . . . 58 Frequency distribution of specific gravity in 'Heinz 19' variety cucumbers . . . 60 Frequency distribution of specific gravity of 'Earli Pik' variety cucumbers . . . 61 Frequency distribution of specific gravity of 'Premier' variety cucumbers . . . . 62 Bloater formation in mechanically harvested 'Heinz 19' variety cucumbers sorted into fluid specific gravity groups . . . . . 63 Figure Page 23—24 Bloater formation in mechanically harvested 'Earli Pik' variety cucumbers sorted into fluid specific gravity groups . . . . 64 25-26 Bloater formation in mechanically harvested 'Premier' variety cucumbers sorted into fluid specific gravity groups . . . . 67 27-28 Percentage-of—sample-that-sink curve and bloater formation curves from density- sorted 'Heinz 19' pickling cucumbers . . 69 29-30 Percentage-of—sample-that-sink curve and bloater formation curves from density-sorted 'Earli—Pik' pickling cucumbers . . . 70 31-32 Percentage-of—sample-that-sink curve and bloater formation curves from density-sorted 'Premier' pickling cucumbers . . . . 71 33 Bloater formation in two sizes of mechanically harvested cucumbers density-sorted into more dense sinkers (S) and less dense floaters (F). Each variety brined in separate quartered 300-bu tank. Four replications per treat- ment . . . . . . . . . . 73 34 Bloater formation in two sizes of mechani- cally harvested cucumbers density-sorted into more dense sinkers (S) and less dense floaters (F) and brined in quartered 300-bu tank. Eight replications per treatment . 76 xi LIST OF SYMBOLS, ABBREVIATIONS, AND NOMENCLATURE Brine = Solution of water and 5 to 15% sodium chloride Brine stock = Cucumbers fermented and stored in brine bu = Bushe1(s) C = Temperature, degrees Centigrade cm = Centimeter(s) cm3 = Cubic centimeter(s) F = Temperature, degrees Fahrenheit ft3 = Cubic feet gal = gallon(s) gm = gram(s) Green stock = Newly harvested cucumbers as received at the processing plant ID = Inside diameter in. = Inch(es) 1b = Pound(s) L/D = Length-to-diameter ratio m1 = Milliliter(s) MSU = Michigan State University OD = Outside diameter r = Coefficient of linear correlation (+1.0 or -l.0 = perfect correlation) SD = o = Standard deviation(s) SE = Standard error (of coefficients) xii SEE SG ><| ~<> Standard error of estimate specific gravity Sample mean = mean of independent variable values in sample Grand mean = mean of all values in test Estimated value of Y for a given value of X (by least-squares method) Field department size grades: 1/2 in. to 3/4 in. diameter 3/4 in. to 1-1/16 in. diameter 1-1/16 in. to 1-5/16 in. diameter 1-5/16 in. to 1-1/2 in. diameter 1-1/2 in. to 1-3/4 in. diameter 1-3/4 in. to 2 in. diameter Processing plant size grades: 8/10 = approximately 800 to 1000 cucumbers per 45-ga1 cask = approximately 1-9/16 to 1-7/8 in. diameter 10/12 = approximately 1000 to 1200 cucumbers per 45-gal cask = approximately 1-7/16 to 1-9/16 in. diameter xiii CHAPTER I INTRODUCTION Michigan and United States Cucumber Production Statistics Cucumbers (Cucumis sativus L.) grown for pickles are a very important crop in Michigan and the United States. Pickling cucumbers make up 54% and 11% of the value of nine principal processing vegetable crops in Michigan and_ the United States (U.S.), respectively. In Michigan, for the 5-year period 1970-1974, average acreage exceeded 25,000 acres and average production exceeded 100,000 tons, valued at over $10 million annually (USDA 1974) (Appendix Al). During this period, production in the U.S. averaged nearly 600,000 tons valued at nearly $60 million (USDA 1974) (Appendix A2). For the past 57 years (1918-1974), Michigan has produced more pickling cucumbers than any other state with the exception of two years. Yet, for the 1970-1974 period, Michigan has only produced an average of 17.4% of the nation's production. Michigan led the nation in the adoption of once-over mechanical harvesting. During 1973 and 1974 over 90% ov Michigan's acreage was harvested mechanically (Appendix A1). Michi- gan's mechanized acreage accounted for over 70% of the nation's mechanization. Many Michigan pickle 1 2 processing plants also receive cucumbers from the South and Southeast. Therefore, the volume of cucumbers brined and processed in Michigan is much greater than just Michigan's production. Fermenting cucumbers form,at times, internal cavities or hollows of varying size. Such cucumbers, known in the trade as bloaters, appreciably decrease the market value of the finished product. United States Losses due to Bloater Formation For the period 1970-1972, the annual loss to the U.S. pickling industry due to bloater formation is estimated to be $5 million (Appendix A3). Approximately 55% of the 1972 U.S. crop was brined (placed in salt solution for storage) until processed (Moore 1973). The remaining 45% was processed as received into fresh-pack products. Evaluation for Internal Voids 'Pioneer' variety cucumbers examined for internal voids during 1970 and 1971 indicated that over 40% of the 1-1/2 to 2 in. diameter fruits had a carpel separation (or void) of 1/32 :hi. inside diameter (ID) or larger (Marshall et a1. 1971, 1972). This observation raised a question as to whether there would be a difference in density between the cucumbers with voids and those 3 without voids. Sneed and Bowers (1970) reported a highly significant correlation (r = .804) between carpel separation and balloon bloating in brined cucumbers. The question of the relationship between cucumber density (specific gravity) and bloater formation appeared worthy of detailed investigation. Preliminary Experiment -- 1971 In 1971, a trial experiment was conducted to determine green stock density distribution and the relationship between green stock density and brine stock bloating (Marshall et al. 1973). Cucumbers were density-sorted into groups with aqueous solutions contain- ing ethanol with specific gravities (SG) of .975 to .955, at .005 increments. Each of the fluid specific gravity groups was placed in a separate cloth bag and brined in the same commercial brine tank along with the original load of cucumbers. The results indicated that balloon bloater formation was inversely related to green stock SG. Lens bloater formation seemed independent of green stock SG. If the total sample had been density-sorted to obtain a sinker/ floater ratio of 20/80, a 75% reduction in balloon bloater formation in the high SG fraction would have been predicted. These favorable results justified detailed investigation which the is the subject of this thesis. 4 Objectives To determine that bloater formation in brine stock is related to specific gravity of green stock pickling cucumbers. To measure individual cucumber specific gravity as related to: a) fruit diameter, b) variety and c) date of harvest for a given planting. To measure physical and quality factors such as: a) reducing sugar content, b) carpel strength, and c) brine stock firmness as related to specific gravity. To test the density-sorting principle utilizing commercial prototype density-sorting equipment. CHAPTER II REVIEW OF LITERATURE Published literature reveals extensive and long-time use of specific gravity (86) as an aid to determining quality of many agricultural products. Specific Gravity Separation Vegetables. It was recognized as early as 1847 that the amount of dry matter in potatoes influenced quality, and that the dry matter content was related to SG. Heinze et al. (1955) cited Smee's 1847 treatise, The Potato 31223) where Smee listed 160 kinds of potatoes ". with the weight of each tuber and the 86, which will roughly indicate the quantity of solid material, and consequently the value of each kind.” Among the first to use brine solutions to determine the 86 of potatoes were the German investigators Schultze (1871) and Fresenius (1881), as cited by Blood and Prince (1940). Specific gravity has also been correlated with culinary and processing qualities of potatoes (Blood and Prince 1940, Kelly and Smith 1944, and Kunkel et al. 1952). Specific gravity separation for quality based upon various attributes of maturity have been correlated in 6 peas, sweet corn, lima beans, snap beans, tomatoes, and carrots (Crawford and Gould 1957, Gould 1957, Kattan et a2. 1968, 1969, 1970, Kelly and Smith 1944, and Strietelmeier 1959). Strietelmeier (1959) found that total soluble solids, average grade, average color (a/b ratio), and average firmness in non-puffy 'Rutgers' tomatoes all showed a correlation with SG (r = .90, .92, .84, and .92, respectively). Average size did not correlate with SG. An 86 of .9750 was the most efficient point for separating less dense culls. Strietelmeier also found that mature cull watermelons (which generally had "hollowhearts”) could be sorted from acceptable melons at an SG of .8700 to .8900 (depending on variety) with an efficiency of 90%. The only references discussing cucumber or pickle density have been Leonard (1958), Mulvaney (1958), and Samish et a1. (1957). Leonard reported an average SG of 0.96 (range of .89 to 1.00) for one pickling variety tested, 'Wisconsin SMR-12.' Mulvaney reported the mean SG of two lots of unidentified slicing cucumbers was .940 t .006 and .936 t .010. Samish et al. reported that the SG of green stock cucumbers increased from .965 SC to 1.000 within 9 days after immersion in fermentation brine where no internal cavities developed. However, where cavities did develop, the 86 decreased in proportion to cavity development and to a low of .802 for very large 7 cavities. None of these researchers reported on any results or effects related to green stock density. Fruits. Wolfe et a1. (1974) found positive correlations (r > .98) between blueberry density and maturity. Density-sorting is being considered as an alternative to aerodynamic separation to remove green fruit from mature fruit. DeBaerdemaeker and Segerlind (1974) presented data for 'Midway' strawberries where mean berry weight and berry color correlated with SG. Small (green) berries had the lowest mean SG and mean weight (.886 and 3.96 gm,‘ respectively). Large (red) berries had the highest mean SG and mean weight (.921 and 7.83 gm, respectively). Their data suggest that pink and pink-white berries could effectively be separated with an 86 of .911. Vis et a2. (1969) successfully separated low-density unpollinated dates from pollinated fruit with water- separation methods. Nichols and Reed (1932) reported a relationship between SG and texture, color, and sugar content of dried prunes. Grierson and Hayward (1959) described how oranges damaged by low temperatures commonly tend to hang on the tree, showing little or no external evidence of freeze damage. In any but the most severe of freezes, injury is limited to certain areas in the grove or to certain fruit on individual trees, and thus the 8 harvested crop generally includes a mixture of sound and damaged fruit. Because of the drying of the frozen tissues, the SG of the injured fruit tends to decrease in the weeks following a freeze, so that after a month or more the SG of the damaged oranges is lowered enough to afford a means of separating them from sound unfrozen fruit. Separation of less dense frost-damaged oranges from the more dense unfrozen fruit can be achieved by using a solution whose SC is between that of the sound and the frozen fruit and hence the sound oranges sink and the damaged fruit float. Stout (1964) reported orange juice yield to be correlated (positive) with fruit SG. Oil crops. Cottonseed density was found to have a highly significant correlation (positive) with germination and growth (Tupper et al. 1970). Pawlowski (1963) found a highly significant correlation (negative) between SG of safflower, flax, rape and dehulled sunflower seeds and oil content. Equipment. Pflug et al. (1955) described the use of a potato separator using brine for continuous operation sinker/floater separation. ‘In the potato chipping industry, it is possible to produce more uniform chips by first separating according to SG (Kunkel et al. 1952). Another method of SC separation is to drop the fruit 9 into a flowing stream ofliquidin.which an adjustable vane separates the damaged oranges which rise more rapidly than the sound ones which rise slowly or even sink (Perry and Perkins 1968). Equipment utilizing this method is manufactured by American Machinery Corporation1 and Brogdex Companyz. A modification of this method is obtained by lowering the fruit below the liquid surface and releasing it into the liquid flow rather than dropping the fruit into the sorting solution. Kattan (1968, 1969) used this technique with salt brine to successfully sort tomatoes for color and maturity. Equipment utilizing this method is manufactured by Food Technology Corporation3 and FMC Corporation“. This latter method uses horizontal dividers or skimming conveyors to remove the various grades of fruit. None of these separation methods are new, all having been used in California after the bad freeze of 1913 and subsequently (Sunkist Growers 1957). In 1917, Chace (1919) found that separation of frost-damaged oranges from sound oranges was not lAmerican Machinery Corporation, Division of Aeroglide Corporation, Box 3228, Orlando, Florida 32802. 2Brogdex Company, 315 W. Grant St., Box 8551, Orlando, Florida 32806. 3Food Technology Corporation, Division of General Kinetics, Inc., 12300 Parklawn Dr., Rockville, Maryland 20852. “FMC Corporation, Riverside Division, Box 219, Lindsay, California 93247. 10 entirely reliable, for some low-density fruits were accepted by the machines tested while some fairly high-density fruits were rejected. The results showed that the correlation of frost damage with 86 was far from perfect. Grierson and Hayward (1959) confirmed Chace's results. Porritt et a1. (1963) described and illustrated flotation separation equipment for sorting apples with water core (a physiological disorder) from those without water core. The sorting method was similar to that described above for citrus. The fruit were dumped into an alcohol solution at the deep end of the tank where the more dense fruit sank and the less dense fruit floated. Tests showed that satisfactory separation in 'Delicious' apples could be obtained with a solution SG adjusted to about .877. Methods of Measuring Density and Specific Gravity The density of a body in the number of units of mass divided by a unite of volume. The specific gravity (SG) of a body is the ratio of its density to the density of water. Archimedes' principle. The mass of a solid body may always be obtained by weighing, but the volume of an irregular solid cannot be obtained from a measurement of its dimensions. The principle of Archimedes provides 11 a simple method of finding the volume of a solid heavier than water. The approach can be used for irregular bodies; for the volume of an immersed solid is numerically equal to its reduction in mass in water. Hence mass of body density = specific gravity = loss of mass in water If the body floats, its volume may still be obtained by attaching a mass heavy enough to force it beneath the water surface. If we let Ba denote the weight in grams of a body in air, Mw denote the weight of the attached mass alone in water, and BMw denote the weight of the body and attached mass both submerged in water, then: B a body specific gravity = _ Ba + Mw BMw Example: 125.0 SG 125.0 + 26.1 - 23.6 = '980 An application of Archimedes' principle was described by Hulsey et al. (1971) as a rapid and precise technique which measured the buoyancy force texerted by a fluid on a submerged body which is directly 1“e1ated to the volume of the body. The technique used 12 an Instron Universal Testing Machine with a submersion device made with metal prongs which diverged downwards and trapped or held the buoyant body below the liquid level. High-density liquids, such as saturated salt brines (S6 = 1.204) or organic fluids such as carbon tetrachloride (SG = 1.594), gave the best results. Pycnometer method. The pycnometer is often used to determine the SG of liquids. It is also useful for determining the 56 of bodies less dense than water, such as cucumbers. The pycnometer consists of a glass bottle larger than the object being tested with a ground stopper which has a capillary tube which serves as an overflow for the excess water to be exhausted (Casimir et al. 1967). If we let Ba denote the weight in grams of the body in air, PW denote the weight of the pycnometer full of water, and PBW denote the weight of the pycnometer, the body within it and the remaining volume filled with water, then: body specific gravity = Ba + PW - pBw Example: _ 125.0 = SG ‘ 125.0 + 1048.3 - 1045.8 '980 13 Hydrometer method. This method is based on the principle that objects will float or sink in a given solution depending on the density of the solution. A series of solutions are made up to known densities using a standard 86 hydrometer. Commonly, brine solutions are used for objects that sink in water and alcohol or other low-density fluids mixed with water for objects that float in water. In actual practice, an object is placed in the highest SG solution and then in progressively lower 86 solutions until the object just barely sinks or freely sinks. With this technique, the SG of the object will be equal to or higher than the 86 of the particular solution in use. The above criteria is used as a practical separation method. However, the actual SG of an object would more accurately be determined if the solution SG was adjusted until the object neither sank nor floated but was suspended at mid-depth in the solution. The density distribution of a sample of a number of objects would be established by determining the specific gravity group designation for each individual object. Specific gravity, determined by this method, would be relative (to the nearest .005) rather than a precise SG value for each object as compared to either of the two methods discussed above. Therefore, any discussion of cucumber SG categorized by this technique 14 must be in terms of specific gravity group rather than of actual SG. Another application of the technique which has been used extensively in the potato chipping industry since 1950 was developed by Smith (1950). The potato hydrometer consists of a special basket and calibrated float-scale as also described by Murphy and Goven (1959). Exactly 8 1b of potatoes are put into the basket and into a container of water. The average SG of the potatoes is read directly at the water level on the scale within the instrument. This is a very convenient method for determining average SC for a given lot of objects that sink in water. It does not permit measuring the 86 of individual objects, however, nor of objects that float in water. CHAPTER III PROCEDURES Size Grading Cucumber diameter was measured, in certain tests, to the nearest 0.1 in. Diameter was defined as the distance between two rectangular blocks touching each side of a fruit resting on a horizontal surface (Fig. 1). In other tests, cucumbers were size graded according to one of the size grade designations discussed below before being density-sorted. The pickle industry commonly designates field department size grades for pickling cucumbers as follows: 1A = 1/2 in. to 3/4 in. diameter 1B = 3/4 in. to 1-1/16 in. diameter 2A = 1-1/16 in. to 1-5/16 in. diameter 2B = 1-5/16 in. to 1-1/2 in. diameter 3A = 1-1/2 in. to 1-3/4 in. diameter 3B = 1-3/4 in. to 2 in. diameter Processing plants generally require narrower diameter ranges, especially in the 3A and 3B sizes which are mainly used for slices and/or spears. There- fore, plant grading equipment have a narrower range and do not coincide with the field grade sizes. Diameter ranges will be specified for each test in the results 15 16 sections. Processing plant size designations refer to the average number of cucumbers contained in a 45-gallon cask (PPI). Some of the designations are 8, 10, and 12. Number per De51gnation 45-gal. cask" Approx. diameter 8/10 800/1000 1-9/16 to 1-7/8 in. 10/12 1000/1200 1-7/16 to 1-9/16 in. DIAMETER WOOD BLOCK 'l'UTI'TTII'IIIT' 0 I 2 3 INCHES Fig. 1. Method used to measure cucumber diameter. 1These are general figures since the L/D ratio (length to diameter) may vary from lot to lot and from variety to variety, and hence will affect the volume of cucumbers of a given diameter. 17 Generally, 2.0 in. diameter cucumbers are the largest size grade commercially utilized. Depending upon variety and seed development, slightly larger sizes may be utilized. Bloater formation generally increases as diameter increases because of maturation. Bloater formation therefore is monitored in the largest commercial field department size grade (No. 3 - 1.5 to 2.0 in. diameter). Therefore, much of the data presented (such as the laboratory scale studies) is on size grade No. 3. The data on the commercial prototype density-sorting, however, is presented on the slightly smaller processing plant size grades 10/12 and 8/10 (1-7/16 to 1-7/8 in. diameter). Density Determination Methods Used Pycnometer. The pycnometer used was specially constructed and followed the typical design described by Casimir et a1. (1967). It was constructed with an extra- wide mouth (from a standard Pyrex 71/60 ground-glass tapered joint). Its internal volume was approximately 500 ml and accepted cucumbers up to 5.5 in. in length. Flowing tap water was used which maintained a relatively constant temperature for each run and ranged from an estimated 60 to 65°F. Each individual cucumber was weighed dry, then put into the pycnometer which in turn was overfilled with water. The stopper was gently but firmly inserted into the tapered pycnometer mouth. The 18 surplus water overflowed out the joint with the last few drops being exhausted through the capillary tube located in the stopper. Care was exercised to avoid retention of any air bubbles within the pycnometer. The pycnometer was carefully wiped dry before weighing on a 0-2000 gm capacity single-pan direct reading electric balance. Hydrometer. A11 SG determinations with the hydro- meter method were made using a series of l90-proof (95%) U.S.P. (United States Pharmacopoeia) ethanol solutions prepared at intervals of .005 SG ranging from .990 to .940. Standard glass SG hydrometers are calibrated at 60°F and require a correction at other temperatures. Prior to the 1973 season, test calibration solutions of ethanol and water were prepared at 60°F. The temperature of the solutions was elevated to over 80°F, reduced to 45°F and then raised back to the initial 60°F, taking hydrometer readings throughout the calibration test. A chart was prepared incorporating the correction factors obtained. A complete description of the density-sorting techniques including the temperature correction chart was prepared (Appendix A4). The SG hydrometer used was calibrated at .0005 SG scale increments. Cucumbers were density-sorted by putting each cucumber into successively lower .005 86 interval solutions until it sank. The highest SG solution in which a cucumber would sink was defined as its fluid 19 specific gravity group. After the cucumbers were sorted into specific gravity groups, each group was placed in a separate cloth bag and brined in the same commercial brine tank along with the original load of cucumbers. Laboratory Scale Experiments Relationship of specific gravityyto diameter (1972). Cucumbers for this experiment were obtained from various locations in Michigan. The SC determinations were made by the pycnometer method. Measurements were taken on .4 to 2.6 in. diameter cucumbers. The data points for small-diameter fruit are an average of all those of a given size, or all that would fit into the pycnometer, rather than of a single cucumber's. For example, all 0.5 in. diameter fruit were measured as a composite -- as many as 10 or 20 fruit at a time. Only two or three 1.0 in. diameter fruit would fit in the pycnometer at one time. All cucumbers 1.4 in. diameter and larger were measured one-at-a-time. Relationship of sample location within a fruit to specific gravity (1972). The pycnometer method was used to determine the SG of the various parts or sample locations of individual cucumbers obtained from various locations in Michigan. The seven sample classifications were as follows: 20 = whole cucumber = stem end half = stem end carpel stem end wall = blossom end half = blossom end carpel VOMbMNI—I' II = blossom end wall The seven parts were evaluated in the order of their classification number. Fruit diameter ranged from 1.5 to 2.4 in. For classifications 3, 4, 6 and 7, approx- imately l in. of the stem end or blossom end was cut off of the respective halves to expose the developed carpel. A narrow knife was used to carefully core and separate the carpel sample from the wall sample. Relationship of multi-pick harvest dates and variety to gpecific gravity (1972). Harvest date is defined as the date of multi-pick harvest for successive hand pickings from the same plots. Cucumber SG measurements were taken on 15 varieties from the MSU Department of Horticulture plots in the vicinity of East Lansing, Mich- igan. The plots were planted in a randomized block design with three replicates. Cucumbers 1.5 to 2.0 in. diameter were harvested by hand on three successive harvest dates from the same plots. This, therefore, did not simulate once-over harvesting but rather multiple harvesting. Specific gravity was determined by the pycnometer method, generally on 12 fruit per replicate 21 per variety. Sometimes no fruit were available, or fewer than 12 were available. A mean SG was calculated for each variety lot and was used in an analysis of variance (Cress 1973). One missing value was calculated for each block when required (Cochran and Cox 1957, p. 302). Seven of the 15 variety plots produced sufficient fruit that could be used in the test. Relationship of variety to specific gravity (1973, 1974). Cucumber SG measurements were recorded on 1.5 to 2.0 in. diameter fruit of many varieties from the MSU Horticulture plots. Generally, the samples evaluated were mechanically harvested and contained 80 or more fruit in 1973 and 25 or more in 1974. The SC determinations were made by the hydrometer method obtaining a specific gravity group distribution. The mean SG and standard deviation were calculated from the recorded specific gravity group data. Relationship of carpel strength and harvest date to specific gravity (1972, 1973). Cucumber SG and carpel strength measurements were recorded on many varieties from the MSU Horticulture plots. Generally, 25 fruit were evaluated per variety for three different harvest dates from the same plots. Cucumbers were 1.5 to 2.0 in. diameter. The carpel strength measurements were performed with 22 a 6 mm slice thickness, 3/16 in. diameter probe and a 1-3/8 in. inside diameter (ID) annular support (Hooper et al. 1972a). The carpel strength was measured with the load cell and chart recorder of the Instron Universal Testing Machine located in the MSU Department of Food Science and Human Nutrition. Relationship of specific gravity, diameter and harvest number to sugar content (1972). The cucumbers used in this experiment were the same as those described above under "Relationship of harvest number and variety to specific gravity (1972)." Twelve lots (11 varieties) were analyzed for sugar content. Reducing sugar deter- minations were made with the Lane-Eynon method (AOAC 1970). The tests were conducted by the MSU Department of Food Science and Human Nutrition. After necessary measurements were recorded on each individual fruit to determine its SG by the pycnometer method, the fruit was prepared for a subsequent sugar determination. Each fruit (1.5 to 2.0 in. diameter) was cut cross-sectionally, retaining the center 2 in. section. The center section was numbered with a black felt pen. The sections were placed in a plastic zip-lock bag numbered with the variety code number. The sections were frozen and analyzed 5 to 6 months later. The SG of each fruit was calculated and the values for each variety lot arranged in numerical order. Generally, 23 the three sections with the highest and the three lowest SG values per variety lot of 12 were analyzed. Relationship of brine stock firmness to specific gravity (1973). Up to now, all discussions about quality have been with regard to measurements on green stock cucumbers. Firmness in brined cucumbers or salt-stock is another measure of quality, indicating how much undesirable softening may have occurred while in the fermentation brine. Firmness is measured as the force (lb) required to puncture the wall of a brined cucumber with a 5/16 in. diameter tip of the USDA Fruit Pressure Testerl (Magness and Taylor 1925, Bell et al. 1955). The PPI-USDA "Firmness ratings" for size grade No. 3 cured salt-stock are as follows (Etchells and Hontz 1973): PRESSURE TEST FIRMNESS RATING 19.5 lb and above Very firm 15.5 through 19.5 lb Firm 10.5 through 15.5 lb Inferior 4.5 through 10.5 lb Soft 4.5 lb and below Mushy The green stock cucumbers used in this experiment were a portion of those described above under "Relation- ship of variety to specific gravity (1973, 1974)." 1Available from: D. Ballauf Mfg. Co., 619 H St. N.W., Washington, D. C. 24 After the size No. 3 cucumbers were sorted into specific gravity groups by the hydrometer method, each cucumber was marked with its respective specific gravity group number with a black felt pen. Immediately prior to brine stock evaluation a firmness reading was recorded for each fruit. Brining of samples. After density-sorting into .005 specific gravity groups, each group was placed in a separate cloth bag and brined in the same commercial brine tank with the original load of cucumbers. Brine stock evaluation. About 100 days later, the brine stock cucumbers were evaluated for internal defects by members of the National Pickle Growers Association's (NPGA)l Industry Advisory Committee. Each brine stock cucumber was cut longitudinally. Defects were classified as balloon bloaters (a single large longitudinal cavity) and lens bloaters (many small lens-shaped gas pockets) as illustrated and specified by Etchells et al. (1968) and Monroe et al. (1969). If a bloater contained both balloon and lens defects, it was classified as a balloon bloater. Honeycomb bloaters (small cavities that form extensively around individual immature seeds) were not 1The NPGA has since been dissolved and has been replaced with the Ad Hoc Committee for Pickling Cucumber Research at Michigan State University. 25 prevalent and have been included with the lens bloater category. Commercial Prototype Density Sorting Detailed investigations (1972). The density-sorting principle was tested on a commercial scale with two varieties: 'Heinz 19' at H. J. Heinz, USA, Zeeland, Michigan (one 300-bu tank), and 'Earli Pik' at Aunt Jane's Foods Division, Comstock Foods, Croswell, Michigan (one 300-bu tank). One of two criteria were used to density- sort the two size grades of a given variety: 1) constant SG solution for different sinker/floater ratios for the 'Heinz 19' variety and 2) constant sinker/floater ratio (20/80) using different 86 solutions for each size grade for the 'Earli Pik' variety. Floaters were classified as those cucumbers that floated in a sorting solution with a given 86 and sinkers were classified as those that sank in the same solution. The 'Heinz 19' cucumbers were brined August 15, 1972, about 35 hours after being mechanically harvested. The 'Earli Pik' cucumbers were brined August 21, 1972, about 40 hours after being mechanically harvested. Detailed investigation (1973). The density-sorting principle was tested commercially for the second year With two 300-bu tanks (replicates) of 'Premier' variety cucumbers at Aunt Jane's Foods Division, Comstock Foods, 26 Croswell, Michigan. The sorting criterion was: constant sinker/floater ratio (20/80) using different SG solutions for each size grade. The cucumbers were brined August 30, 1973, about 30 hours after being mechanically harvested. The rest of the procedures were the same as in 1972. Dgtermination of sorting solution specific gravity. Following is the procedure used to determine the S6 of the sorting solution necessary to cause the desired percentage of cucumbers to sink. For each test, 225 cucumbers were randomly selected and sorted by the hydrometer method into specific gravity groups at .005 SC increments. Each cucumber was put into successively lower SG solutions until it sank. The highest SG solution in which a cucumber would sink was defined as its specific gravity group. The data were then plotted as percentage-of-samp1e—that-sinks (PTS) curves. After the PTS curve had been plotted for a lot, a decision had to be made as to the desired percentage of sinkers. A small percentage of sinkers (i.e., 5 or 10%) would reduce bloater frequency, but would result in an excessive amount of product to produce any appreciable amount of stock to brine and therefore would be rather inefficient. On the other hand, with a large percentage of sinkers (i.e., 30 or 40%), less total product would have to be handled but the bloater reduction benefit 27 would be greatly reduced. Therefore, there exists a trade-off or a break-even point. In all but one case, a 20/80 sinker/floater ratio was arbitrarily selected as discussed below. To actually determine the required solution SG, the desired sinker percentage, such as 20%, point (A) in Fig. 2 was selected. The 20% PTS was projected to the right until it intersected the desired PTS curve. Next a line was projected straight down from the intersection until it hit the fluid SG border, either point (B) or (C). The tank of sorting solution would then be adjusted to the appropriate SG (B) or (C) for the size grade being sorted. To show how critical the selection of the solution 86 is, assume a single 86 (.973) had been chosen (point (D) Fig. 2), such as with criterion 1) above to density- sort both size grades in the same SG solution. The sinker/floater ratio for size grade 8/10 would have been 9% (point (E)) and 43% (point (F)) for the lO/lZs. There- fore, it is very important that accurate size grading be done before density-sorting and that care is taken when plotting and reading the PTS curve. The 20/80 sinker/floater ratio used in the discussion above could be used commercially whereby 100% of already graded, size grade No. 3 cucumbers could be density-sorted. The floaters (80%) would be processed immediately into fresh-pack products. The sinkers (20%) Fig. 28 100 - , I972 90- E3() '°/'2"“‘I\ 70- 8/10 60- SOD/W) 40* 30- (A) 20/ 1 PERCENTAGE OF SAMPLE THAT SINKS 10- (B) I (C) 01% - r .985 .975 .965 .955 FLUID SPECIFIC GRAVITY GROUP Percentage of green stock cucumbers that sink in a solution of a given specific gravity. Size grade 10/12 = l-7/16 to 1-9/16 in. diameter; 8/10 = 1-9/16 to 1-7/8 in. diameter. 29 would be brined. Early or late in the season, when green stock receipts are lower, generally all cucumbers are fresh-packed and none would be density-sorted. How- ever, at the peak of the season, some must be brined because of the inadequate capacity of the processing plant for fresh packing. Density-sorting could provide a means of separation so that only the least likely to bloat cucumbers would be brined. Density-sorting equipment. The experimental density-sorting tank used had approximately 1000-gal capacity (3 ft wide and 4 ft deep) and was equipped with a conveyor at each end (Fig. 3). The conveyor that removed the sinkers extended to the bottom of the tank. The floater conveyor extended about 1 ft below the solution level. Sorting was a batch-type process with about 8 or 9 bu being dumped into the density-sorting solution at a time. The floating layer of cucumbers was gently probed with a broom to permit any sinkers held within the floating layer to sink to the conveyor below. The sinker conveyor was then operated and most of the sinkers removed. The next step was to remove the floaters. The two conveyors were not operated simultaneously in order to minimize subsurface solution agitation. During the density-sorting operation, the tank contained 850 to 900 gal of sorting solution. 30 Fig. 3. Side view of experimental tank used to sort green stock pickling cucumbers according to density into floaters and sinkers. Brining. Density-sorted 10/12 floaters, 8/10 floaters, mixed 10/12 and 8/10 sinkers, and non-density- sorted mixed 10/125 and 8/105 as control were placed in each quadrant (individual compartment) of a 300-bu commercial brine tank. Included also were the bags of sorted .005 specific gravity groups. Brine stock evaluation. After approximately 100 days the brine stock pickles were evaluated at the same time and in the same manner as described earlier for the laboratory scale experiments. CHAPTER IV RESULTS AND DISCUSSION Laboratory Scale Experiments Relationship of specific gravity to diameter (1972). Figure 4 presents the relationship between green stock specific gravity (SG) and diameter for a sample of 'Pioneer' variety cucumbers. It clearly indicates a highly significant negative correlation; as cucumber diameter increased, SG decreased. Linear regression coefficients and other related information for three varieties are shown in Table 1. One explanation for the decrease in specific gravity as diameter increased is the effect of maturity on gaseous volume in cucumber tissues. Fellers (1964) estimated a 17 to 27% increase (depending on sample location) in gaseous volume in size grade No. 3 'SMR-l8' variety cucumbers compared to No. 2 size fruit. ”The coefficient of linear correlation (r) is a measure of the degree to which variables vary together or a measure of the intensity of association" (Steel and Torrie 1960, p. 183). Therefore, the coefficient is the extent of correlation between two variables or a measure of how dependent the Y variable is on the 31 32 .mhonesoso kuowhm> .poocoflm. mo pouoEmfiw owfimuso ou xufi>mhw owmwoomm mo aficmcofiumaom m.~ o.~ . m.— A.c_v mmkmz<_o Q.— _ m. as C ps 0 II 1— x m_o.o n moo._ NNm_ u > (. .v 0mm. omm. 0mm. 0mm. 0mm. coo.— .wam ALIAVBS JIdIDHdS 33 .opmeflumo mo House ohwocmum .macwom mumo mo .02 .ucoflowwwooo mo house wumocmum mmm ”mafia u : mfio>oa Hoo. mo omon u u «e: Hoocmofimficwwm H< numoohoucfl > u < mm “pcofiofimmooo coaumaophoo u p O .wocuos mohmscm-ummoa xn .mhouosm mmpsoo x mo oSHm> co>wm m How Axufi>mhm UMMHoommo > mo osHm> woumsflumm u > ”x < u w" o.~ on ca. He wmoo. ow.- NNOO. emo.- mmoo. oo.H xuam «ea N :muhmmm o.N on me. He vvoo. «««mo.- NHoo. mNo.- oNoo. moo.H pofisohm m.~ ow om: we «moo. «exmm.- NHoo. mHo.- mHoo. moo.H Hooaofim o mmm A mm H< mm < m.:wv omCMH : xumwhm> HouoEmfio "mucowofiwwoou :ofimmopmom smocwq .nmumHo mowuoflpm> oopnp How souoEmHo mowmuno ow xufl>mpw ofimfioomm mo magmnoflumflou ecu mo mucofiowmwooo mafia :oflmmouwom .H oHQMH 34 independent X variable. A value of the coefficient (r) will always be between +1 and -1. Plus or minus 1 represents perfect correlation, while zero indicates no correlation at all. Thus, in the three varieties discussed above, a high degree of negative correlation existed between SG and diameter. The standard error of estimate (SEE) is a measure of the variation from the least-squares regression line. Relationship of sample location within a fruit to specific gravity (1972). The mean 86 for whole cucumbers and their various parts are shown in Fig. 5. Each data point is the mean SG of the number of cucumbers shown within the parentheses following the variety name. The data points are not continuous in nature, but for clarity of presentation and for ease in following the trend of a given variety, the data points have been connected. One standard deviation is shown for two varieties. There is a marked increase (.030 to .040 SC) for the two carpel or core samples as compared to the wall samples. Since the stem-end half and the blossom-end half in Fig. 5 are parts of the same whole fruit, one would expect the SG of the whole fruit to be the average of the two respective half-fruit data points. Inspection of the figure indicates this is not the case. One possible explanation of this is sampling error. Another SPECIFIC GRAVITY AVERAGE I Fig. .03 .02 .Ol .00 .99 .98 .97 .96 .95 3S I972 ‘ q .1 4 d “EII‘ (NARI: A6) I I l I I l 1 J WHOLE STEM END BLOSSOM STEM END BLOSSOM STEM END BLOSSOM FRUIT HALF HALF WALL END WALL CARPEL END CARPEI. SAMPLE DESCRIPTION Average specific gravity of whole and various portions of pickling cucumbers. Numbers parentheses indicate number of cucumbers sample. One standard deviation is shown two varieties (1.5 to 2.0 in. diameter). within in for 36 explanation is the possible presence of internal voids in the fruit. During SG measurements of the whole fruit, the voids could have been filled with gas which gave a low SG reading. During SG measurements of the fruit halves, any voids would be filled with water resulting in higher 56 readings. During the tests no voids were observed. However, there may have been small or undetected voids. Using a similar analogy to the above discussion, the SG of the wall halves should be lower than the SG of the intact halves. This was exactly the case for the Heinz dwarf (6) variety and the 'Pioneer' (11) variety. In addition, there were similar observations for the blossom end of the 394C x 4108H (Parth) (4) sample. Since the carpel region is consistently more dense than the wall region it would be of interest to know what percentage the carpel area is of the total cross- sectional area to see what effect the carpel volume may have on the decrease of SC as OD increases. In addition, the influence of SG on diameter should be evaluated. In 1973, 23 slices of 'Mariner' variety and 20 slices of 'Premier' variety ranging from 1.0 to 2.2 in. diameter were photographed. Carpel area and total area were measured from enlargements with a planimeter. Carpel area as a percentage of the total area was plotted against OD. The least-squares regression line for the 'Premier' variety showed a positive relationship 37 indicating carpel percentage increased as OD increased (35.9% for 1.0 in. OD to 38.5% for 2.0 in. OD, a 2.6% increase). On the other hand, the 'Mariner' variety had a definite negative trend with carpel percentage decreasing as OD increased (34.3% for 1.0 in. OD to 29.1% for 2.0 in. OD, a 5.2% decrease). First of all, this means that the carpel is less than one-third of the total volume when you consider that the percentages above are from center cross-sections and that there is no carpel at the ends of the cucumber. Secondly, the 2.6% increase in area for the 'Premier' variety would increase the SG as diameter increases assuming no change in the SG of either the carpel or wall regions but merely a change in areas. Instead SG decreased with diameter. The 5.2% decrease in area for the 'Mariner' variety is not sufficient to account for approximately a .020 86 drop from 1.0 to 2.0 in. diameter, especially since the seeds are increasing in density and dry matter as they mature. Water is used by cucumber breeders to separate sound developed seeds which sink from light undeveloped seeds which float. The density of a given cucumber is really a composite of densities for many different sections within the fruit. Primarily, the cucumber is made up of two distinct volumes; the carpel and the wall. As described above, the carpel is more dense than the wall. Therefore, the SG of a given cucumber, or more 38 accurately, the average specific gravity (SGavg), is equal to the product of the wall percentage (PW) and the wall SG (SGW) plus the product of the carpel percentage (PC) and the carpel SG (SGc)' In equation form: SGavg = (Pw X SGw) + (PC X SGC) The carpel could even be divided further into components such as seed embryos, gelatinous material, immature and mature seeds, voids, etc. The point is that there are a number of factors contributing to cucumber density. The thickness or volume of cucumber walls is much larger in some varieties than in those described above (Scott 1975). Where wall thickness is greater, the effect of a dense carpel would be minimized and the average density would be lower. Fellers (1964) estimated the gaseous volume of size grade No. 3 cucumber carpel tissue to be 7.0% and the wall tissue to be 13.7%. The nearly double gaseous volume in the wall tissue as compared to carpel tissue is another explanation for the difference between the specific gravity of the two types of tissue. 39 Relationship of multi-pick harvest dates and variety to specific gravity (1972). The relationship of harvest dates and variety to SC is shown in Table 2. (Harvest dates). Based on an analysis of variance, a highly significant SG difference at the .001 level existed between the first, second and third harvest dates. The SC decreased by .010 with each successive harvest. This trend may be caused by changes in soil moisture and/or environmental conditions which influence growth of the plants and fruit. Shaw (1974) found S6 of apples decreased with three successive harvests (approx. 2-week intervals). It was shown earlier in this investigation that SG decreased as cucumbers matured (increased in diameter) for a single harvest. The above data indicate that mean SG (of a given diameter) decreased as the vine matured (successive harvests). (Variety). Based on the analysis of variance, sample means of SC for different varieties did not differ significantly. The highest mean SG ('Pioneer' variety) and the lowest mean SG ('Bounty' variety) had an SG difference of .0052 for the first harvest (which would simulate once-over harvesting). For the second and third harvests, neither variety above remained the highest or lowest 86 but their SG 40 Table 2. Relationship of multi-pick harvest dates and variety to specific gravity. Second and third harvest samples are from same plots as for first harvest (1.5 to 2.0 in. diameter) (1972). Harvest Date*** variety Variety gzgvgsgc mean lst 2nd 3rd g so Pioneer .9845 Hi .9730. .9667 .0178 ..9747 Hi Ranger .9832 .9675 Lo .9635 .0197 .9714 Frontier .9818 .9758 Hi .9651 .0167 .9742 Spartan Jack .9801 .9730 .9529 Lo .0272 .9687 Lo Premier .9799 .9743 .9688 Hi .0111 .9743 Mariner .9799 .9716 .9632 .0167 .9716 Bounty .9793 Lo .9679 .9619 .0174 .9697 Harvest mean SG .9813 .9719 .9632 variety range SC .0052 .0083 .0159 .0060 *** All significantly different at .001 level. 41 difference remained nearly constant, .0051 and .0048, respectively. Meanwhile, there was an unexplained increase in the differential between the highest and lowest SG means for all varieties (.0052, .0083 and .0159) for the first, second and third harvests, respectively. Relationship of variety to specific gravity (1973, 1914). The results of experiments involving the measurement of SG on 10 variety lots (nine different varieties) during 1973 are shown in Table 3. The sample SG means and standard deviations are listed. Tukey's w-procedure was used to evaluate the difference between SG means (Sokal and Rohlf 1969, p. 238). The maximum difference between mean 86 values was .0246; however, if the lowest mean SC for the 'Mariner 2' variety is disregarded, the difference is reduced to less than half (.0102). In spite of this small difference, the mean SG values for different varieties were significantly different. Tukey's LSR.05 value was .0034 and LSR.01 was .0040. The results for 65 variety lots (55 different varieties) in 1974 are presented in Table 4. The varieties are ranked in descending order according to their mean SG. The difference between the maximum and minimum mean 86 (.0240) was virtually identical to the 1973 difference (.0246). Tukey's w-procedure was used 42 Table 3. Relationship of cucumber variety to sample mean specific gravity (1.5 to 2.0 in. diameter) (1973). Variety Standard saggie Rank Name dev1at10n SG 1 1 Carolina .0063 .9841 a 2 Pickmore .0066 .9813 ab 3 Premier .0070 .9793 be 4 Perfecto Verde .0074 .9786 bcd 5 Pioneer .0082 .9783 bcd 6 Spartan Jack .0059 .9757 cde 7 Bounty .0063 .9755 cde 8 Earli Pik .0052 .9748 de 9 Mariner (1) .0048 .9739 e 10 Mariner (2) .0084 .9595 f Grand Mean .9761 f .0066 1Sample means followed by the same letter are not significantly different at the 1% level (Tukey LSR.01 = .0040). 43 Table 4. Relationship of cucumber variety to sample mean spec1fic gravity (1.5 to 2.0 in. diameter) (1974). VarIety Date Sample Sample standard mean Rank Name harvested deviation 55 ]/ I Perfecto Verde 8-12 .0046 .9822 a 2 Carollna 9-11 .0049 .9796 ab 3 Sumter 8-17 .0037 .9795 ab 4 Fx 3904 8-17 .0064 .9787 abc S 38ND 8-11 .0047 .9784 abc 6 4585 9-11 .0045 .9780 abc 7 (920 X “10811)X MSU 9429 8-17 .0058 .9779 ab: 8 Premier 9-11 .0056 .9772 abcd 9 H50 319R 8-27 .0073 .9770 abcd 10 (9210 x 4108H)x H50 9429 8-17 .0058 .9764 abcde 11 XP 1040 8-17 .0050 .9756 abcdef 12 38MB 8-17 .0081 .9755 abcdef l3 Unknown-Hm C. 8-13 .0052 .9753 abcdef 14 CSND 8-17 .0065 .9753 abcdef IS Bounty 8- 6 .0056 .9753 abcdef 16 Premier 8-12 .0063 .9748 abcdefg 17 38c2 8-17 .0072 .9741 abcdefgh 18 1159 9-11 .0052 .9740 abcdefgh I9 Pickmore, Scab-Res. 8-12 .0079 .9740 abcdefgn 20 Premier 8-12 .0062 .9736 abcdefghi 21 3488 X 8519 8-17 .0055 .9735 abcdefghij 22 Score 9-11 .0071 .9734 bcdefghij 23 Premier 8-12 .0047 .9734 bcdefghij 24 Hariner 8-17 .0060 .9728 bcdefghijk 25 FIHYBR. 130 8-17 .0057 .9724 bcdefghijk 26 (920 x 4|08H)X 5802 A 8-17 .0091 .9723 bcdefghijkl 27 Pickmore, Scab-Res. 8-12 .0066 .9722 bcdefghijkl 28 SHR 18 8-17 .0058 .9719 bcdefghijklm 29 Goddess Hyb. 8-17 .0063 .9714 bedefghiiklm 30 Spartan Salad 8-27 .0058 .9714 bcdefghiiklm 3| Imp. Pioneer 8-17 .0065 .9706 cdefghijklmn 32 3885 9-11 .0064 .9704 cdefghijklmno 33 HSU 32490 8-27 .0057 .9702 cdefghljklmno 34 HSU 2246 8-27 .0044 .9702 cdefghijklmno 35 3859 8-17 .0051 .9690 defghijklmnop 36 3534 0 8-17 .0059 1.9688 defghijklmnop 37 Perfecto Verde 8-20 .0075 .9685 defghijklmnop 38 Spartan Advance 8-17 .0060 :9677 efghijklmnopq 39 Spartan Jack 8-27 .0052 .9674 fghljklmnopq 40 850 1830 8-27 .0104 .9674 fghijklmnopq 4| Spartan Advance 8-21 .0069 .9673 fghijklmnopq 42 MSU 9402 8-27 .0079 .9672 fghljklmnopq 43 National Pickling 8-27 .0064 .9672 fghljklmnopq 44 Spartan Advance 8-27 .0073 .9664 ghljklmnopqr 45 921 x 319 + 20$ 9-10 .0055 .9662 ghljklmnopqr 46 Spartan Progress 8-27 .0066 .9660 hljklmnopqr '47 H50 8821 8-27 .0067 .9657 hijklmnopqr 48 $0 25 8-21 .0077 .9650 ljkImnopqr “9 Pioneer 8-27 .0073 .9648 jklmnopqr 50 0Y1“ X 319" 3-17 .0063 .9648 jklmnopqr 51 SR-SSIF 8-27 .0060 .9644 klmnopqr 52 (3946 X 4108)! 5802A 8-17 .0081 .9643 kImnopqr 53 HSU 33936 X SCéOlH 8-27 .0076 .9642 klmnopqr 54 H50 356 8-27 .0086 .9636 Innopqr 55 Plxle 8-27 .0053 .9636 Imnopqr 56 vs sun 18 8-27 .0075 .9636 Imnopqr 57 Score 8-27 .9085 .9634 mnopqr 58 H50 3946 8-27 .0073 .9632 mnopqr 59 Green Spear 8-27 .0078 .9626 nopqr 60 921 X 319 + 10% 9-10 .0063 .9626 nopqr 6| SC 23 8-27 .0061 .9620 nopqr 62 394 x 319 + 202 9-10 .0063 .9618 opqr 63 sc 60|H 8-27 .0075 .9614 pqr 64 CY 14 8-27 .0885 .9594 qr 6S H50 3940 8-27 .0073 .9582 r Grand mean .9699 + .0057 I/' Sample means followed by the same letter are not slgnlflcantly " different at the .01 level (Tukey LSR 0' - .0087) 44 to evaluate the difference between SG means. Tukey's LSR value was .0075 and LSR was .0087. .05 01 In spite of the fact that the 1972 analysis of variance indicated that variety was not significant, the 1973 and 1974 data show variety differences to be highly signficant (.01 level). As indicated in Fig. 2, a small change in SC, whether between varieties or between size grades of a given variety, will result in a substantial and undesirable change in the sinker/floater ratio. These SG differences may occur due to differences in soil, variety, fertilization, cultural practices, and environmental conditions during the growing season. Many of the variety lots were brined. They were brined in 5-ga1 tanks as described by Baker et a1. (1973). When the brine stock was evaluated in late 1974, very limited bloating had occurred. As a result correlation between bloater formation and SG has not been established for a wide selection of varieties. It should be noted that in general, though not documented here, a trend exists. Varieties such as 'Carolina' which are considered most resistant to bloating are generally the most dense and varieties which are least resistant to bloating such as 'Pixie' are the least dense. The 'SC 601H' variety generally has a thick wall (Scott 1975), a low bloating frequency (see Table 5), and is at least one exception to the above trend. 45 o m H AN8 0 c m mHm wconpm mHoo om . opmHooa o m e mom m w «H m AHm -nQfiH 900:0Hm m x mm NAN H m mm mNN H002 szm om: H3 H3 HS 23 H8 E E Ewo umon pmon pmon newconum umon umon uonm Aumconum 0500x000: $84 :03 Hem H 0 an m u 8:00.800: 23 cooHHmm H0980 oguocofi .H o. 0 H .H m > Homnmu . NAmH Han .HmuoHo .Ho 00 noxmm HnouoEwHo .cH o.~ ou m.Ho woumHsoocH ummox .mxcmp Hmm-om .moumoHHaon 030 no woman ”Mucum ocHnn m0 mcHumoHn :00HHmn ucoscomnsm one :oHumnmaom Homhmo Hooum coohw how mooconomme kuoHnm> .m «Home 46 Relationship of carpel strength and harvest dates to specific gravity (1972, 1973). Research discussed by Hooper et al. (1972a and 1972b) and presented by Baker et al. (1973) indicates that cucumber carpel strength and balloon bloater formation are inversely proportional (Table 5). The results of the present investigation indicate that green stock SG and balloon bloater formation are inversely proportional. These results would suggest a direct relationship between carpel strength and green stock SG. Thus, when the cucumber carpel strength is high, green stock SC is also high and lens bloaters result instead of balloon bloaters; the carpel is strong enough to resist balloon bloater formation. (Carpel strength - 1972). Two varieties ('SC 601H' and 'MSU 381M') have been shown to exhibit a widely separated resistance to carpel separation or weakness (Baker et al. 1973, Wilson 1974). It seemed logical that there might be some relationship where the known weak carpel strength phenotype ('MSU 381M' variety) might have a low SG, the intermediate carpel strength phenotype ('Pioneer' variety) would have an intermediate SG and the strong carpel strength phenotype ('SC 601H' variety) would have a high SG. Table 6 presents the mean SC for the same three varieties as Table 5. The mean SG for the weak and intermediate phenotypes followed 47 Table 6. Relationship of harvest dates and carpel phenotype to sample mean specific gravity (1.5 to 2.0 in. diameter) (1972). Harvest Variety Harvest MSU 381M - Pioneer . SC 601H mean No. Date Carpel Phenotype SG weak mESISEE Strong lst 8-22 - .972 .966 .9690 2nd 8-25 .959 .967 .961 .9623 3rd 8-30 .968 .971 .969 .9693 4t11 9-7 .972 .972 .971 .9716 variety .9663 .9705 .9668 mean SG the presumed relationship, but the strong phenotype's SG was almost as low as the SC for the weak variety. A possible reason for the strong phenotype's low SC is that it has a wall thickness which is more than average (Scott 1975). (Harvest dates - 1972). Specific gravity means are presented in Table 6 for each harvest date and carpel phenotype. The SC for the first harvest was mid- range in magnitude for the intermediate and strong pheno- type. The SG was lowest for all three varieties on harvest date 2. For all three varieties the 56 increased 48 for the third and fourth harvest dates. The inconsistency in SC for a given variety may have been related to changes in soil moisture and/or other environmental conditions. (Carpel strength - 1973). The results of this investigation (eight varieties) are shown in Figs. 6-13 and summarized in Table 7. The individual varieties are listed in descending order based on the slope of the best-fit least-squares regression line. The dependence of carpel strength on SG ranged from a positive correlation for the 'Earli Pik' variety (r = .50*) to virtually no correlation for the 'Perfecto Verde' variety (r = .02 NS). The SEE indicates that the variance from the regression line or scatter of the data generally decreased as the dependence of carpel strength on SG decreased with variety. The causes for these diverse relationships between carpel strength and SG are not clear at this time. Specific gravity means (from Table 3) and total bloater formation in 5-gal tanks are also shown in Table 7. Bloater formation was small and was generally independent of mean carpel strength and mean SG for different varieties. Relationship of specific gravity, harvest date, and diameter to sugar content (1972). Reducing sugar contents were measured on 12 variety lots (11 varieties) with CARPEL STRENGTH (GRAMS) Figs. 600 500 400 300 200 100 600 500 400 300 200 49 Fig. 6 a O “ 'Earli Pik' 0 P 1973 ' O O ”// 8 [,3/’ T I _//IJ// ' *- ,/-1 g; , T ////JL////I§’ . - I// r = 50 I I I I I I I .955 .960 .965 .970 .975 .980 .985 .990 Fig.7 _, 'Carolina' : P 1973 ° 100 I u 1 l l I r .955 .960 .965 .970 .975 .980 .985 .990 FLUID SPECIFIC GRAVITY GROUP 6 and 7. Carpel strength measurements of green stock cucumbers sorted into fluid specific gravity groups. 600 500 400 300 200 100 600 CARPEL STRENGTH (GRAMS) 500 400 300 200 100 50 Fig.8 'Spartan Jack' 3 1' I973 FHL 9 'Pioneer' 3 b 1973 2 . E . . A ' I . 3 r = . 1457': IT" I I l I I I .995 .960 .965 .970 .975 .980 .990 FLUID SPECIFIC GRAVITY GROUP Figs. 8 and 9. Carpel strength measurements of green stock cucumbers sorted into fluid specific gravity groups. 51 600 Fig. 10 500 . 'Bounty' _ 1973 a 8 400 ; 300 i 200 '4 u r =.L|»S* E '00 1 I l 1 I l I ‘5 T’ .955 .960 .965 .970 .975 .980 .985 .990 E £2 a CI 5 600 :1 Fig. 11 CL g 500 q 'Mariner' b L) 1973 400 300 200 'Ii .- r =.21 '00 I 1 l 1 .1 1 1 .955 .960 .965 .970 .975 .980 .985 .990 FLUID SPECIFIC GRAVITY GROUP Figs. 10 and 11. Carpel strength measurements of green stock cucumbers sorted into fluid specific gravity groups. CARPEL STRENGTH (GRAMS) Figs. 400 300 200 100 500 400 300 200 100 12 52 Fig.12 H 'Premier' _ 1973 J a I- a O : ~ g 3 L1 .1 . , . Y 9 a ‘ t r =.27 1 T I 1 1 1 1 .940 .945 .950 .955 .960 .965 .970 .975 .980 Fig.13 1 'Perfecto Verde' _ I973 * 1 4 ‘e‘ 51 i 1 . 8 a o . O W I- r =.02 I 1 l I J I I .940 .945 .950 .955 .960 .965 .970 .975 .980 FLUID SPECIFIC GRAVITY GROUP and 13. Carpel strength measurements of green stock cucumbers sorted into fluid specific gravity groups. .uc0HuHmm0oo coHpmH0nnou u n muconwHemHm uo: u m2 ”mo. 0 « "00:00HwHame Honcho qu>mnw onHo0Qmo 00Hm> x 00>Hm 0 now Hmsnnw-4umc0num Homhmoo > m0 03Hm>_w0umsmwmm u m < < 000530 m0 5.20 Emwcmum a mum ”05H .0 003m 0 < 30000035 > u 0.4. ”x u of .mn0pmoHn 0m>p 0:0H + :ooHHmmN .HuHsnw p00 mouHHm N .000050000 mNo m0sHm> om mo 0m0n0>0 mH :00:a 53 . . . . 0 . 0090> comm m mm mz No uh NQH + A w H H AHN ouo0mnom mono. m.~m mz 5N. ¢HOH oon - o.NH N.oNN 00HE0nm 04 ammo. 0.0m mz HN. ommH mNOH- H.m o.m- n0aHHmz mmnm. o.wm «me. momm mem- N.H u.mm~ zucsom mono. H.Hw «me. mmom mwov- o.v H.omN H0000Hm $3. 5.: «3.. $3 28- o 5mm: 803. 50.8% H: Hewm. m.mHm mmm n < < NHmHOH meamm 035000 2307:; :09: 0H 9:0 m m 30083300 03000500 .80ch cmwwmfimm gowc0pum Homnmu .HmamHo Hn0u0EmH0 .cH o.m 0» .:H m.Ho mH smsoncu o .mem :H ozonm >0H>mnw UHMHo0mm 0H0Hm momn0> zumc0num H0mnmo m0 m0cHH pHm-um0n mo mucoHonm0oo :chmonm0n 0000HH 0:0 .>HH>0nm onHo0om 000E .coHqupow h0umoHn .cumc0num H0mnmo :00: .n 0Hnmh 54 three replications for each. Each increase of 1% in sugar solids results in an increase of 86 by .004 (Handbook of Chemistry and Physics 1956, p. 1925). The range in reducing sugar content for individual fruit sections was 1.90% (3.10% high, 1.20% low). The correlation between reducing sugar content and cucumber 86 was not significant. Differences in 86 within a given variety was not due to sugar content. (Harvest date). Table 8 presents the relationship of harvest date to reducing sugar content. The harvest dates were about 5 days apart. The sugar content was found to be highest for harvest No. 2, and lowest for No. 3. All harvest dates were significantly different at the .01 level. This inconsistency may be related to soil moisture or other environmental factors and/or sampling techniques. (Diameter). The relationship of reducing sugar content to diameter for all varieties is presented in Table 9. There was a slight tendency for the sugar contents to decrease as diameter increased. Lower (1975) found both positive and negative relationships between sugar content and diameter. No definite conclusions can be drawn based on these limited scale experiments. Relationship of brine stock firmness to specific gravity (1973). The relationship of brine stock firmness 55 Table 8. Mean reducing sugar content (percentage) of 11 cucumber variety lots (10 different varieties) for three harvest dates from the same vines (1.5 to 2.0 in. diameter cucumbers) (1972). Harvest date ** Variet lst 2nd 3rd Variety 7 Mean SD Mean SD Mean SD mean 352£t%3) 2.21 Hi .15 - - 1.88 .27 2.05 Crusader 2.20 .21 2.35 Lo .31 1.55 Lo .25 2.03 Bounty 2.16 .10 2.88 .23 1.91 .23 2.32 Hi SMR 58 2.16 .29 2.69 .10 1.92 .46 2.26 Premier 2.16 .26 2.69 .13 1.62 .17 2.16 gggit??) 2.11 .24 2.51 .28 1.76 .21 2.13 Pioneer 2.06 .14 3.10 Hi .31 1.76 .29 2.31 Mariner 1.99 .17 2.56 .18 1.91 .45 2.15 Pixie - - 2.50 .23 1.79 .25 2.15 Frontier 1.97 .23 2.87 .19 1.57 .20 2.14 Pickmore 1.94 .17 2.35 .24 1.66 .13 1.98 Ranger 1.79 Lo .11 - - 1.96 Hi .51 1.88 Lo 2238“ 2.07 .21 2.65 .31 1.77 .31 ** All significantly different at .01 level. SD = Standard deviation S6 :oH00H>00 0000:00m u am . . . . . . :00: 05 H co N mm H mm H cm H mm H 0000E0HQ wN. oo.H - - 0N. 00.H mm. mm.H 0N. mm.H Hm. 00.H «e. mn.H - - No. HN.~ - - m0. nm.~ mm. HN.N 0000 mm. wu.H ow. oo.~ mm. mu.H mm. mm.H um. mm.H mm. N5.H 0m0>00m am :00: am :00: mm :00: am :00: mm :00: mm :00: oo.~ mm.H om.H mw.H ow.H mn.H mm.H OH.N -.~ mo.~ 0H.~ :00: 0000E0HQ NN. mm.H mm. mn.H He. wH.N hm. 0m.H 0H. vu.H um. H~.N um. Nu.~ mm. mv.m - - Nm. mn.~ 0000 on. em.H on. em.H um. mo.~ no. NH.N mm. Ho.N 0m0>00m mm :00: am :00: mm :00: am :00: am :00: on.H mo.H oo.H mm.H om.H H.:HV 0000E0Hm .mmanV 00000 0m0>00a 000:0 0cm 0000E0H0 00 0000H00 00 w 0Hn0e :H 000:0000: Hm0H00H00> oHV m0oH >00H00> HH mo H0w00:0000mv 0:00:00 000:0 w:Ho:000 :00: .m 0HD0H S7 to SC for six varieties is presented in Fig. 14. The 'Mariner' and 'Bounty' varieties generally exhibited a negative correlation with firmness increasing as 56 decreased. The 'Carolina' variety exhibited a less consistent trend with a generally negative correlation. 'Earli Pik' and 'Perfecto Verde' varieties had the lowest firmness of the six varieties. The 'Earli Pik' variety had no consistent trend. The 'Perfecto Verde' variety had a generally positive correlation. It should be noted that those varieties with moderate to strong negative correlation had "Firm" or "Very Firm" ratings. The 'Earli Pik' and 'Perfecto Verde' varieties had an "Inferior" firmness rating. One would expect that as density decreased, firmness would decrease. One explanation would be the decrease in density due to internal voids. This would result in brined cucumbers which are softer and have a lower firmness reading. This trend is generally illustrated by the 'Perfecto Verde' variety. An examination of the 'Mariner' variety curve, which is in the desirable firmness range ("Firm" and "Very Firm"), shows a complete reversal of the above trend. For some reason, when the samples are removed from the brine, and the average firmness is above the "threshold" of about 16 lb, the firmness decreases as density increases. S8 .fl00005000 .a: o.~ 60 0.00 0H:E00 :H 000055030 00 0005:: 000oH0:H 0000:0:000: :H00H3 0000552 .0::o0w :0H>00m onHo0Q0 0H3Hw 00:H x0000 :000w 00 000000-:0H0:00 0003 00:0 0000:5030 00:00: mo 000:E0Hm know mo_mmmz_ zm_u SNIlVH SSENNUId zm_m >mw> gnome >h_> < 30- _ 204 L 10.. U _ § . O 14 as "‘ “I .980 .975 .970 .965 1960 .955 .950 FLUID SPECIFIC GRAVITY GROUP Figs. 25 and 26. Bloater formation in mechanically harvested 'Premier' variety cucumbers sorted into fluid specific gravity groups. 68 through 30. The curves illustrate the use of the PTS curve in determining the solution 86 necessary to obtain a given sinker/floater ratio. When the 'Heinz 19' variety (Figs. 27 and 28) was density-sorted with a constant 86 solution for both size grades (.971 SC) 25% of the 10/12s and 11% of the 8/105 sank. The 'Earli Pik' variety (Figs. 29 and 30) was density-sorted with a constant sinker/floater ratio (20/80) using solutions at .976 SC and .971 SC for 10/12s and 8/10s, respectively. Based on previous discussions, it is clear that in order to maintain a constant sinker/floater ratio that solutions of different SG are necessary for density- sorting different size grades and varieties. The bloater formation curves are useful in predicting the extent of bloating that would have occurred if the sample had been density-sorted in a particular sinker/ floater ratio. For example, in Fig. 31, a 20/80 sinker/ floater ratio (point A) would have resulted in a predicted balloon bloater formation of 1.6% (point B). The actual percentage of balloon bloating in the 20% sample would have been 8% (1.6%/20%). If none of the sample had been density—sorted, the balloon bloater formation would have been 26.6% (point C). Therefore, a 70% reduction [(26.6% - 8%)/26.6%] would have been accomplished in the entire sample by density-sorting at a 20/80 ratio. 69 10 Fig. 27 I-7/I6 t0 *- 3“ 1-9/16 in. 5‘9“ GOOD diameter éflg’ .. Ifiifit. LENS BLOATERS BALLOON .2 BLOATERS Z A —- F- (I) Z LIJ I— u < m I LLI '- 3, LL] ..l 2 O- O I l: g g 100 u. a: Fig. 28 ... q l-9/l6 to 0 s I. E E 8° l-7/8 in. (31:0 6000 5 3 diameter 60‘}? TOTAL 5 5' 60‘ 1972 «35'3“, _ SAMPLE a. Q .33 ?~ <5 LENS 40~ . BLOATERS 2°"‘"‘ l I BALLOON BLOATERS O 1” IA” H .975 .970 .965 .960 .955 .950 .945 .940 FLUID SPECIFIC GRAVITY GROUP Figs. 27 and 28. Percentage-of-sample-that-sink curve and bloater formation curves from density-sorted 'Heinz 19' pickling cucumbers. PERCENTAGE OF SAMPLE THAT SINK BLOATER FORMATION (PERCENT) Figs. 70 100 Fig.29 30. I-7/I6 to Q $5 1-9/16 in. Po? 0000 diameter g/x’ & 60-1 I972 TOTAL 40‘ SAMPLE 20-_——-—-—— LENS BLOATERS BALLOON 0‘ L; “‘{*:__——TTT’TTf———_—4 BLOATERS .985 .980 .975 .970 .965 .960 .955 100 Fig.30 l-9/I6 to d k. :- 8° l-7/8 in. $53 0000 diameter ’ 3’ I 2 TOTAL 60* 97 I SAMPLE 40- - ..____.._..._ I. LENS 20 BLOATERS BALLOON 0 1 ‘ I BLOATERS .980 .975 .970 .965 .960 .955 .950 FLUID SPECIFIC GRAVITY GROUP 29 and 30. Percentage-of—sample-that-sink curve and bloater formation curves from density-sorted 'Earli Pik' pickling cucumbers. PERCENTAGE OF SAMPLE THAT SINK Figs. BLOATER FORMATION (PERCENT) 71 100 Fig. 3| I-7/I6 to 804 - I'9/I6 In. 4k g: diameter “5°07 GOOD I TOTAL I (D 60* 973 " SAMPLE 40‘ r - LENS /(A) ; BLOATERS 20* ----- (c)z;ir BALLOON BLOATERS 0_ (a) .985 .980 .975 .970 .965 .960 .955 100 Fig. 32 l-9/i6 to 30‘ 1-7/8 in. I diameter 3‘ 5:5 GOOD I \ L TOTAL SAMPLE 404 ‘ I A, I LENS ; T_I" BLOATERS I BALLOON } BLOATERS .980 .975 .970 .965 .960 .955 .950 FLUID SPECIFIC GRAVITY GROUP 31 and 32. Percentage-of-sample-that-sink curve and bloater formation curves from density-sorted 'Premier' cucumbers. pickling 72 Commercial Prototype Density-Sorting Bloater formation (1972). The results of density- sorting for 'Heinz 19' and 'Earli Pik' varieties are presented in Fig. 33. The graphs illustrate that balloon bloater formation was less in sinkers than in floaters. Total bloater formation was least in the sinkers in both varieties. ('Heinz 19'). For the 'Heinz 19' variety, balloon bloater formation in the sinkers was significantly lower (.05 level) than for the floaters. Balloon bloater formation in the smaller size grade was significantly I lower (.05 level) than in the larger size. Balloon bloater formation in the smaller size grade was signifi- cantly reduced (.05 level) from 36.3% in the floaters to 2.0% in the sinkers (a 94% reduction). This reduction was the largest for all tests conducted. In the larger size grade, balloon bloater formation was significantly reduced (.05 level) from 70.0% in the floaters to 38.8% in the sinkers (a 45% reduction). Lens bloater formation occurred to a larger extent in the sinkers for both size grades but was not signi- ficantly different at the .05 level. The extent of total bloater formation (balloon + lens) in the sinkers was less than in the floaters for both size grades but was not significantly different at Fig. 33. DEFECTS - PERCENT OF SORTED SAMPLE 73 I LENS BLOATER 90 - g BALLOON BLOATER I972 d) 80 'HEINZ 19' 00' 'EARLI PlK" +1 0. 70 ~ ~— _ '- 60 - .. F r .. msmz 50 ~ .. .. F m am — .. ~' .. 40 . ‘2 .._ 0 "3°- __ "‘7 3 co 3 .. r 00' o .. +- 505 505 253- +' w 30 1 E .. o‘ I- : ... °‘ m °° +' 20 ~ N .A S ° '"“ +' 35:5 "' 35355 33533 ‘0 55525 o 05 .. 5§§*':£ '“ £5: 5' ... °° sees? ... N 0' ‘38 ii??? -' 10 ~ M — +1 ... S 25552 a. ... I: 55 iii? :5 O .253: 2212: 11:12 - """ ° ::::: 53533 55555 O """ C) I £3N=fis =fi= sfi= _ gm ‘ :3 ‘55: S F S F S F S F i-7/l6 I-9/16 I-7/l6 I-9/l6 T0 T0 T0 T0 1-9/16 i-7/8 I-9/I6 l-7/8 SIZE GRADE (in.) Bloater formation in two sizes of mechanically harvested cucumbers density-sorted into more dense sinkers (S) and less dense floaters (F). Each variety brined in separate quartered 300- bu tank. Four replications per treatment. 74 the .05 level. Total bloater formation in the smaller size grade was reduced from 54.8% in the floaters to 26.0% in the sinkers (a 53% reduction). In the larger size grade, total bloater formation was reduced from 85.0% in the floaters to 69.9% in the sinkers (an 18% reduction). ('Earli Pik'). Balloon bloater formation in the 'Earli Pik' variety was significantly lower (.05 level in sinkers than in floaters but not significantly different between size grades. Balloon bloater formation in the smaller size grade was reduced from 14.5% in the floaters to 5.3% in the sinkers (a 63% reduction). In the larger size grade, balloon bloater formation was reduced from 21.5% in the floaters to 10.5% in the sinkers (a 51% reduction). Lens bloater formation was slightly less in the sinkers for the smaller size grade but was slightly larger in the sinkers for the larger size grade. Total bloater formation in the sinkers was less than in the floaters for both size grades but was not significantly different at the .05 level. The total bloater formation in the smaller size grade was reduced from 52.3% in the floaters to 41.3% in the sinkers (a 21% reduction). In the larger size grade, the total bloater formation was reduced from 67.3% in the floaters to 61.3% in the sinkers (a 9% reduction). 75 Bloater formation (1973). The results of density- sorting 'Premier' variety cucumbers are shown in Fig. 34. In contrast to the generally sizable reduction in bloater formation in the sinkers for the 1972 tests, the 1973 tests were not nearly as dramatic. Balloon bloater formation was less in the sinkers than in the floaters for both size grades, but was not significantly different at the .05 level. Balloon bloater formation in the smaller size grade was significantly less than in the larger size grade at the .05 level. Balloon bloater formation in the smaller size grade was reduced from 52.1% in the floaters to 39.8% in the sinkers (a 24% reduction). In the larger size grade the balloon bloater formation was reduced from 68.4% in the floaters to 58.4% in the sinkers (a 15% reduction). It should be noted that the 70% reduction in balloon bloater formation predicted from Fig. 31, and the dis- cussion on page 68, for 'Premier' size grade 10/12 cucumbers did not occur; instead, a 24% reduction occurred. The extent of lens bloater formation was higher in the sinkers for both size grades but was not significantly different at the .05 level. Total bloater formation in the smaller size grade was less in the sinkers but was significantly greater in the floaters. 76 | LENs BLOATER 9°” a BALLOON BLOATER 'PREMIER' 1973 Fill-- 80“ n—m m +| M m 70" xxut’au ..............[ +I .:::: ppppp uuuuu ----- ..... ..... ..... ..... ..... ..... ..... ..... 50" ..... ..... ..... ..... ..... ..... ..... ..... uuuuu ..... 40-- —.-. l861388 .............. '--~' .... ‘::': a u .......... .......... .............. ........ -------------- .............. 68J++€l3 ........... - ... .... .... ":' ...... _,,_ 3' ..... ...: ..... .... ..... " ...... ..., . ..... +| .::: q ...... .... .::.: ‘- . ------ ..u- ' ' ' .......... ’_ ..... --o- -.-. .o o ............. .............. uuuuuu ..... .............. £2C)- Ema+'$§‘“ am ............... ............. ......... ............... ...... nnnnnn ........... .... ...... .... ....- ...... ._.. DI-t‘ - uuuuu .... """ oooooo .... ""' ..... .... ""'1 . D ..... IIIIIII """"""""""""" .............. --------------- .............. .............. .............. ......... ............... .............. ............ DEFECTS - PERCENT OF SORTED SAMPLE .............. .............. oooooooooooooo nnnnn SIZE GRADE (in.) Bloater formation in two sizes of mechanically harvested cucumbers density-sorted into more dense sinkers (S) and less dense floaters (F) and brined in quartered 300-bu tank. Eight replications per treatment. 77 General discussion. In three density-sorting tests (three varieties, two size grades per variety) balloon bloater formation was significantly less (.05 level) in the sinkers than in the floaters when sorted into sinker/ floater ratios of approximately 20/80. Balloon bloater formation was found to vary considerably (from 2 to 70%). Balloon bloater formation was less in size grade 10/12 compared to the larger size grade (8/10) in each test. When the data are pooled for the three density-sort- ing tests, balloon bloater formation in size grade 10/12 was reduced from 34.3% in the floaters to 15.7% in the sinkers (a 54% reduction). In the larger size grade (8/10) balloon bloater formation was reduced from 53.3% in the floaters to 35.9% in the sinkers (a 33% reduction). When the data from both size grades are pooled, balloon bloater formation was reduced from 43.8% in the floaters to 25.8% in the sinkers (a 41% reduction). Lens bloater formation was greater in the sinkers than in the floaters in each of the tests except one but was not significantly different in any at the .05 level. The best explanation of this observation is that the brined cucumbers which would have been lens bloaters were weak enough internally to permit balloon bloaters to form. Lens bloater formation was not significantly different between size grades in any of the tests (.05 level). When the data are pooled for the three density-sorting tests, lens bloater formation in size grade 10/12 increased 78 from 21.9% in the floaters to 25.5% in the sinkers (a 14% increase). In the larger size grade (8/10) lens bloater formation increased from 23.4% in the floaters to 34% in the sinkers (a 31% increase). When the data from both size grades are pooled, lens bloater formation increased from 22.7% in the floaters to 29.8% (a 24% increase). Total bloater formation was less in the sinkers than in the floaters in each of the tests except one but was not significantly different in any at the .05 level. Total bloater formation was less in size grade 10/12 compared to the larger size grade (8/10) in each test. When the data are pooled for the three density- sorting tests, total bloater formation in size grade 10/12 was reduced from 56.2% in the floaters to 41.2% in the sinkers (a 27% reduction). In the larger size grade (8/10) total bloater formation was reduced from 76.7% in the floaters to 69.9% in the sinkers (a 9% reduction). When the data from both size grades are pooled, total bloater formation was reduced from 66.4% in the floaters to 55.6% in the sinkers (a 16% reduction). The mean 86 for the three density-sorting tests varied from a minimum of .9637 to a maximum of .9704 (a range of .0067) for size grade 10/12. For size grade 8/10, the mean 86 varied from a minimum of .9595 to a maximum of .9667 (a range of .0072). Differences were almost as large between the size grades within a given 79 variety, ranging from .0037 to .0054. Ranges of this magnitude confirm that the solution SG would have to be altered between size grades and varieties with a static flotation separation technique. Density-sorting selectively separates cucumbers according to a physical characteristic (SGavg) that is related to an internal characteristic that may vary between and within varieties such as carpel or suture strength, carpel SG, wall SG, wall thickness, gaseous volume of the various tissues, internal voids, diameter and maturity. This characteristic (SGavg) has been shown to be related to a fruit's resistance to bloat in the fermentation brine. That is, a dense cucumber separated from less dense cucumbers by density-sorting does not prevent bloating per se, by preventing the cause of bloating; but it merely selectively sorts out those fruits more able to resist the cause(s) that result in bloater formation. During one of the commercial density-sorting tests, a container of the sorting solution (86 = .971) was set aside in order to monitor the solution's increase in 56 due to evaporation. The 86 of the solution increased .0020 per hour during sunny daylight hours and .0003 per hour during the night due to evaporation alone. Dilution of the sorting solution was another problem encountered. Dilution can occur in at least two ways. Most cucumbers are either unloaded into water, handled 80 in water, flumed by water and/or spray—cleaned with water during size grading. Any water or fluids retained on the cucumbers will cause sorting solution dilution. Since cucumbers are about 95% water, any cut, broken, or smashed fruit may exude internal fluids and dilute the sorting solution. A static flotation mechanical separator is a low- capacity system but by the nature of its principle it is very accurate. The accuracy is due to the fact that the cucumbers have sufficient time in the sorting solution to sink or float according to their 86 before they are removed from the sorting tank. Other types of mechanical sorters such as those utilizing the rate-of-rise principle (Kattan et a2. 1968, 1969) may not sort cucumbers according to their SG nearly as accurately as the static flotation separator. One major problem anticipated in sorting with the rate-or-rise principle is the effect the shape factor, or length-to-diameter ratio (L/D) of the object being sorted may have on sorting accuracy. This shape factor might be referred to as a hydro—dynamic property which would be analogous to the aerodynamic property of an object moving through air. Whereas the use of the rate-of-rise principle has been used success- fully by Kattan et al. on tomatoes (L/D : 1.0) in a moving stream of water, it is doubtful that the sorting accuracy in cucumbers (L/D = 2.6 to 3.0) would be as high as with the static flotation principle. 81 An adequate random sampling system would have to be developed and routinely followed for each load of cucumbers in order to establish a PTS curve to determine the correct SC for the sorting solution. To maintain‘ a given sorting ratio, each processing plant pallet box of graded cucumbers from a given truck load would have to be kept separate or marked with its proper sorting SG. Density-sorting can be used as a valuable tool in brining research. Depending on the test, it can eliminate another variable and improve the accuracy of the treatment results. It has already been used in cucumber handling research (Heldman et a2. 1974). It can also assist plant. breeders in evaluating new varieties when there may only be a small quantity of fruit available to evaluate. Specific gravity can be measured and still have the fruit brined. Feasibility of density-sorting cucumbers with an ethanol-water solution. The static flotation mechanical separator provided a very convenient approach to density- sorting the cucumbers used in this research. However, before this method is seriously considered for use in a commercial processing plant, a number of observations and/or anticipated problems discussed below should be considered. Cucumbers would have to be accurately size graded before being density-sorted. The 86 of the density-sorting 82 solution would have to be altered for different size grades within a given truck load and probably for differ- ent truck loads and different varieties. This is because of the inverse relationship between cucumber SG and diameter and because cucumber SG varies with differ- ent varieties. The 86 of ethanol—water density-sorting solutions will be adversely affected by evaporation of the ethanol. Dilution may occur from internal fluids released by cut or broken cucumbers or from water retained on cucumber surfaces from handling or grading systems. Residue and/or other studies may have to be conducted to satisfy regulatory agencies that ethanol does not have to be included as an ingredient on the product label. Imbibing of U.S.P. ethanol would be possible and therefore appropriate security precautions would be required. Disposal of old or contaminated ethanol-water solutions may adversely affect the operation of lagoon- type disposal systems and/or may not conform to present or future effluent regulations. The principle of sorting pickling cucumbers into two density groups has been shown to be an advantage in reducing balloon bloater formation. Average balloon bloater formation in three varieties tested was 41% to 54% less (depending on size grade) in the sinkers compared to the floaters. Average total bloater 83 formation was 9 to 16% less in the sinkers compared to the floaters. Average lens bloater formation was adversely affected with a 24 to 31% increase in the sinkers compared to the floaters. The density-sorting principle is worthy. However, at present several actual and potential limitations with the ethanol-water flotation separation method have been experienced or discussed. Other sorting solutions and/or sorting methods may permit the density-sorting technique to be a useful and practical method of bloater reduction. CHAPTER V CONCLUSIONS The specific gravity of 'Pioneer' variety green stock pickling cucumbers was found to have a highly significant negative correlation (r = -.92) with outside diameter. Cucumber specific gravity decreased about .019 for each 1.0 in. increase in diameter. Average specific gravity of the carpel region was found to be consistently higher (.030 to .040) than in the wall region. The average specific gravity of seven varieties evaluated decreased about .010 for each of three successive hand harvests from the same plots. The specific gravity averages of 65 variety lots (55 different varieties) varied from .9822 to .9582 (a range of .0240). Any two varieties whose average specific gravities differed by .0087 or more were significantly different at the .01 level. 84 85 Some varieties such as 'Carolina,‘ 'Earli Pik,‘ 'Spartan Jack,‘ 'Pioneer' and 'Bounty' had a positive correlation between carpel strength and green stock specific gravity. Other varieties such as 'Premier' and 'Perfecto Verde' had no correlation. No relationship was found between carpel strength and bloater formation or specific gravity in limited tests. Reducing sugar content was not related to cucumber specific gravity. Reducing sugar con- tent was significantly different (.01 level) for. three harvest dates from the same plots. The second harvest date was the highest (2.65%), the third harvest date was the lowest (1.77%), and the first was 2.07%. Firmness of brined cucumbers was generally negatively correlated with green stock specific gravity for varieties with "Firm" or "Very Firm" firmness ratings. In varieties with "Inferior" or "Soft" firmness ratings, firmness was generally positively correlated with green stock specific gravity. Balloon bloater formation was inversely related to the specific gravity of the green stock cucumbers. There was no consistent trend 10. 11. 12. 86 between lens bloater formation and green stock specific gravity. In general, total bloater formation was inversely related to specific gravity. A flotation-type mechanical separator was successfully used for two year's tests to density-sort pickling cucumbers. Ethanol-water solutions (with specific gravity of .969 to .977) were used as a sorting medium to cause a selected proportion of a sample of cucumbers to sink (about 20%) and the balance to float (about 80%). Cucumbers have to be size-graded according to diameter before density—sorting. In general, the specific gravity of the density- sorting solution would have to be altered for different size grades, truck loads, or varieties, to maintain a constant sinker/floater ratio. Use of ethanol-water solutions for density- sorting may pose the following problems: a) evaporation of the ethanol, b) dilution of the sorting solution by water retained from cucumber unloading, handling and/or grading systems, c) residue or other studies to satisfy regulatory 13. 87 agencies that ethanol is not an ingredient and d) disposal of used sorting solutions. Green stock cucumbers were density-sorted into two groups -- more dense sinkers and less dense floaters. The results of density-sorting cucumbers (to approximately a 20/80 sinker/ floater ratio) revealed the following for three different varieties, two size grades per variety: a) Balloon bloater formation was less in the sinkers than in the floaters in all tests and significantly less (.05 level) in two of the three tests conducted. b) Balloon bloater formation was less in the smaller size grade cucumbers (1-7/16 to 1-9/16 in. diameter) compared to the larger size (1-9/16 to 1-7/8 in. diameter) and signifi- cantly less (.05 level) in two of the three tests conducted. c) Lens bloater formation was generally greater in the sinkers than in the floaters but was not significantly different at the .05 level. d) Total bloater formation was less in the sinkers than in the floaters in five of the six tests but was not significantly different in any at the .05 level. 14. 15. 88 Density-sorting techniques can be used as a valuable tool in brining research. Depending on the test, it can eliminate another variable and improve the accuracy of the response of the treatment results. Investigations have shown that sorting pickling cucumbers into more dense sinkers and less dense floaters is effective in reducing balloon and total bloater formation in the sinkers. However, at present several actual or potential limitations with the ethanol-water flotation separation method have been experienced or are discussed. CHAPTER VI SUGGESTIONS FOR FUTURE WORK Examine the complex interrelationships in a single experiment of variables such as: cucumber specific gravity (intact and portions), carpel strength, carpel separation, placental hollow brine stock firmness, bloater formation with variety, harvest date, different growing locations and various soil and environmental conditions. Evaluate ultra-sonics for non-destructive internal cucumber quality measurement. 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APPENDICES 96 Appendix Al Acreage, yield, production, value and mechanical harvest pgrientage for cucumbers for pickles in Michigan, 1918- ACREAGE YIELD PRODUCTION VALUE YEAR PLANTED HARV'D TONS/AC BU/AC 000 TONS 9 OF us. 000 5 5/90 1918 31,670 1.22 51 38.76 95 1,227 .76 1919 25,180 1.37 57 39.99 99 1,139,, .79 1920 .0 26,000 .82 39 21.21 96 822 .93 1921 {,3 29.970 I.68 70 99.51 96 2.196 1.09 1922 f 25,050 .96 90 29.05 38 872 .87 1923 3 :3} 26,890 1.03 93 27.70 35 1,280 1.11 1929 j; 3? 35,990 .58 29 20.91 39 _962 1.13 1925 “5 a; 36,810 1.32 55 98.59 29 2,298 1.11 1926 2 E1 25,030 1.01 92 25.23 28 1,030 .98 1927 § 17.350 .72 30 12.99 20 968 .90 1928 ‘2 22,890 1.32 55 30.15 28 1,105 .88 1929 2: 21,000 .70 29 19.61 16 598 .90 1930 33,000 30,000 1.22 51 36.72 21 1,377 .90 1931 23,600 22,000 1.20 50 26:90 20 737 .67 1932 11,000 9,300 .96 90 8.93 22 153 .91 1933 22,000 20,000 1.39 56 26.80 32 982 .93 1939 25,500 22,500 1.10 96 29.89 25 997 .98 1935 31,000 26,000 .96 90 29.96 22 520 .50 1936 29,100 29,990 1.61 67 39.30 27 982 .60 1937 32,700 29,000 1.68 70 98.72 26 1,279 .63 1938 25,200 22,700 1.73 79 90.31 28 1,025 .61 1939, 15,800 13,700 1.99 62 20.38 23 967 .55 1990 32,300 26,500 1.13 97 29 89 20 897 .72 I991 35.500 31.500 1.73 72 59.93 28 1,860 .82 I992 37.900 33,000 1.80 75 59.90 30 2,030 .82 1993 28,100 23,200 1.25 52 28.95 19 1,158 .96 1999 29,300 25,100 1.58 66 9.16, 22 1,323 1 10 1995 39,100 27,900 1.30 59 35.51 19 1,791 1.21 1996 97,800 92,900 1.37 57 58.68 23 9,039 1.65 1997 90,700 35,600 1.96 61 52.11 21 3,091 1.90 1998 95,000 90,000 1.99 60 57.60 29 3,960 1.65 1999 99,100 96,300 1.66 69 76.67 27 3,939 1.20 S97 Appendix Al (Continued) ll Prior to I959 the production reporting unit was bushels (“6 Lb.). ACREAGE Y1ELO PRODUCTION VALUE :fific:é’ YEAR PLANTEO HARV'D TONS/AC Bu/AC 000 TONS 2 OF us 000 s S/Bu ACEEgEEfl, 1950 39,600 33,600 .72 30 29.19 19 2,218 2.20 I951 97,600 99,800 I.S9 69 68.8l 25 9,730 I.6S 1952 98,800 95,800 1.85 77 89.65 26 5.290 1.50 1953 91,700 39,700 2.09 85 80.98 25 5.230 1.55 1959 _38,000 36,200 2.06 6 79.71 25 9,293 1.35 1955 37.500 35.500 2.95 I02 86.90 28 9,395 1.20 1956 38,000 35,800 2.59 106 91.03 28 9,799 1.25 1957 90,000 38,000 3.05 127 115.82 31 5.791 1.20 1958 31,000 28,200 3.53 I97 99.98 28 9,979 I.20 1959 25,000 22,700 9.61 189 109.65 32 5,013 1.20 1960 23,500 20,600 9.82 193 99.29 30 5.173 |.30 1961 26,500 29,900 5.23 209 127.61 31 6,916 1.36 1962 23,800 22,100 5.30 212 117.13 29 5,997 1.28 1963 26,000 29,900 5.60 229 139.99 30 7,335 1.32 1969 25,500 23,700 5.05 202 119.68 28 ,,7,971 1.67 0 1965 17,800 16,500 5.759 2309 99.839 22* 7,589 2.33 2.5 1966 20,900 19,600 6.23 299 122.11 23 11,161 2.29 13 1967 29,600 26,600 9.95 178 118.37 20 13,139 2.77 20 1968 22,900 21,200 9.37 175 92.69 16 9,208 2.98 20 1969 23,100 22,200 9.08 163 ,90.60 18 9,332 2.58 35 1970 29,700 23,200 9.98 179 103.95 18 10.353 2.99 65 1971 25,000 29.500 3.38 135 82.80 15 7,618 2.30 85 1972 28,700 26,000 3.76 150 97.80 17 8,391 2.19 90 1973 27,200 26,900 9.07 163 107.95 18 9,977 2.20 >90 5991979 29,900 27,900 9.23 169_ 115.90 19 19,988 3.13 >90 I975 I976 '977 I978 I979 SOURCE: USDA Statistical Reporting Service From I959 on, the production reporting unit has been tons (SO Lb./Bu. used for calculations). Includes l3,630 Tons harvested but not marketed. Industry Advisory Committee Estimate *** Preliminary DEM l-7S 98 Appendix A2 Acreage, consumption, yield and production of cucumbers for pickles for the United States, 1918-1974. YEAR' O 00 U) 3? ma F‘ 1 <1 ( T i? 1 3 0 Cf) rx 2? a: \ D m t \ 9 .— P‘ > z *7 7 \ S e o 2: 1x \\ :3 Kg. ER :3 l i \ 9 ... 0 0 ¢ I ? o. 1 g e, w ... z 6 5 ... 2: '; 3L 31 ._. 9.1 « — 9 (f) m ‘9 a) 5 5 8» U uJ < .3 n o x . J c: 9? .2 2 CL 1 c: CD c: M u. S? on ;:E 5‘ > uJ O “a Si Z .— 23 J A“ L) C) a) \o q- 01 c3 :3 _ L) VlldVD/Sfll - NOIldwnSNOD 383V/SN01 - 013lA £5 6. E. ETC .5 .5 1: £9 .5 O O '— N .— (000‘1 x) (000‘001 x) SNOl SHUJV NOIlDDOOUd DEM 1-75 99 Appendix A3 Calculations of annual 1055 due to bloater formation in the United States. ASSUMPTIONS: 1. $1,000,000 annual loss because of bloater formation (Etchells and Jones 1951). Since the article reports on a June 1950 talk, the data would have been for the 1949 season or earlier. 2. Average U.S. production of cucumbers for processing: 1947-49 264,000,000 tons 1970-72 574,300,000 tons 3. Average U.S. value of cucumbers: 1947-49 $1.45/bu 1970-72 $2.34/bu 4. Percentage of U.S. production brined: 1947-49 = 90% 1970-72 = 55% (Moore 1973) 5. Increase in bloater formation from 1947-49 to 1970-72 = 235% (Moore 1975) CALCULATIONS: _ . . . bu $ 1970 72. 547.3 million tons X 401§fif X 2.34 BE-X..55 = $29,565,000 value of crop brined 1947-49: 264 X 40 X 1.45 X .90 = $13,781,000 value of crop brined 29,565,000 13,781,000 = 2.15 increased value of crop brined in 1970-72 compared to 1947-49 1970-72 Bloater formation loss: $1,000,000 X 2.15 increase in value X 2.35 increase in bloater percentage = $5,000,000 annual loss in 1970-72 100 Appendix A4 Cucumber density-sorting information sheet describing technique, equ1pment, sorting procedure, data sheet and hydrometer reading chart. CUCUHDER DENSITY SORTING INFORMATION OBJECTIVE: I) Determine average green stock density or specific gravity (5.0.) of different varieties. 2) Determine distribution of density within a gisen sample. 3) Determine effect of geographic location (soil, moisture, temperature. etc.) on density of a given variety. 9) Determine relationship of green stock density to bloater fonnation. SORTING PRINCIPLE USED: Solutions of water and ethanol in 0.005 5.0. decreasing steps. SORTING TECHNIQUE USED: I) Put a few cucumbers at a time in the highest 5.0. pail. if they don't sink, keep trans- ferring each to the next IOwest 5.0. solution until each finally sinks. The highest 5.0. solution a cucumber sinks in is its 5.0. category. EQUIPMENT AND SUPPLIES: hydrometer (.990 - i 0I0), thermometer, 8 to ID plastic Sorting pails (2 to 5 Gal. -- like used in institutional packs -- with lids -- to prevent evaporation when not in use), I Qt. plastic graduated measuring cup, water, ethanol, Instruction Data sheets. INSTRUCTIONS FOR PREPARING SORTING SOLUTIONS: i) Hark pa1ls In .005 5.0. increments from .990 to .995 2) Fill the pails with water to about 65% full for the .990 5.0., decreasing to about 90% full for .990 5.0. (after addition of ethanol pails will be about 70% full). 00 not mix the .955. .950, and .995 solutions until positive they'll be needed. 3) Addition of ethanol to water raises the resulting solution temperature. Therefore. mix approximate solutions ahead of first actual use to permit temperature to equalize. 9) The approximate percentage by volume of ethanol reguired to achieve a given 5.0. initially are shown on the bottom of the data sheet. ACTUAL SORTING PROCEDURE: l) Since the hydrometer is calibrated for a solution temperature of bO'F, corrections must be made to obtain the ”true“ 5 0. category. The correzted h,drometer reauing required is shown on the lewer half of the data sheet. 2) Exam les: Solution Temperature is 70°F: a) For the .985 S.0. category the corrected hydrometer reading is .9839 to obtain a "true" 5.0. of .935. 0) Similarly, to obtain a "true" 5.0. of .990 the hydrometer must read .9362- 3) After solutiOn 5.0. has been adjusted to required hydrometer reading, as outlined above, select sample of ICC or 200 cukes that have been graded to size 3 A (I-i/Z to l-3/9 in.) or 3 B (i-3/9 to 2 in. dia.). They must be free of any mud or dirt for accurate density sorting. Record sample information on top of data sheet. 9) Put ab0ut l/2 dozen cukes into the highest 5.0. solution. Take all that float and shake solution from cucOmbers and hands and transfer to next lower 5.0. solution until each Cuke sinks. If the Cuke sinks in the highest 5.0. solution mixed. make up a new solution .005 5.0. higher. The correct 5.0. category Is the highest 5.0. solution in which each cuke sink: 5) Put sorted cukes into correct 5.0. category trays, buckets or bags until entire sample is density sorted. When done with an entire sample, cOunt cukes in each 5.0. category and record on data sheet. 6) Check solution 5.0. every is minutes. Hake appropriate corrections as required by carry- over, evaporation, dilution, etc. 7) If sorted samples are to be brined, identify bags for brine stock evaluation and indicate on data sheet. 8) Please send copy of data sheet to address shown below. For more Information or Information/Data sheets contact: Dale Marshall, Agr. Engr. USOA-ARS-NCR 207 Agricultural Engineering Dept. Hichigan State University East Lansing. hichigan 9882} DEH 3-79 Phone: 5l7/355-9720 101 Appendix A4 (Continued) DENSITY SORTING DATA SHEET COMPANY DATE HAPVESTED GROHER AND FIELD ADDRESS SAMPLE NO. __ TIME HARVESTED SAMPLE HAS HAND HARVESTED ( :1 DATE EVALUATED TIME EVALUATED SAMPLE VAs HCHE HARVESTED___ g: SOLUTION TEMP °F SAMPLE IS; 3A's _____ 38's _____ MIXED ”’ DENSITY SORTED 6Y UERE SAMPLES BRINEO? COMMENTS VARIETY OROUER ANO‘FIELD COMPANY ADDRESS SAMPLE NO. c, DATE MARVESTED TIME MARVESTEO SAMPLE wAs HAND MARVESTED____ :1 DATE EVALUATED TIME EVALUATED SAMPLE HAS MCHE HARVESTED _ 3' SOLUTION TEMP °P SAMPLE IS: 3A's 38's _____ MIXED “’ DENSITY SORTED 6Y VERE SAMPLES 6RINED7 COMMENTS VAR'ETY NUMBER OF CUCUMBERS IN EACH 50 CATE DRY 0R P .990 .985 .980 .975 .970 .965 .960 .955 .950 .995 .5“0 SfHPLE A SAMPLE 6 ‘IEMP TRUE SPECIFIC GRAVITY CATEGORY GROUPS .F 9910 0985 0980 0975 .970 0965 e960 .955 10.50 1995 .39“ Hydrometer Readinq ReaUIred to Obtain Corrected 5.0. Catecory 96 .9909 .9663 .9617 .9770 .9729 .9676 .9631 .9565 .9539 .9992 .9996 50 .9906 .9661 .9619 .9767 .9720 .9673 .9626 .9579 .9532 .9965 .9936 52_, .9906 .9659 .9611 .9763 .Q716449666 .9621 -9523 .9526 -9976 .9931 59 .9905 .9656 .9606 .9760 .9712 .9669 .9616 .9567 .9519 .9971 .9923 56 .9903 .9659 .9606 .9757 .9706 .9659 .9610 .9562 .9513 .9969 .5915 56 .9902 .9652 .9003 .9753 .9709 .9655 .9605 .9556 .9536 .9957 .9906 60 .9300 .9950 .9600 .9750 .9700 .9650 .9600 .9550449500_.99505.3900 62 .9696 .9696 .9797 .9797 .9696 .9695 .9595 .3599 .9999 .9993 .3392 69 .9997 .9696 .9799 .9793 .9692 .9691 .9590 .9536 .9967 .9936 .9365 66 .9995 .9699 .9792 .9790 .9666 .9636 .9509 .9533 .9961_.9929 .2377 66 .9699 .9691 .9769 .9737 .9669 .9632 .9579 .9527 .9979 .9922 .3369 70 .9692 .9639 .9766 .9733 .9660 .9627 .9579 .9521 .9966 .9915 .9362 72 .9691 .9637 .9763 .9730 .9676 .9622 .9569 .3515 .9961 .9906 -9359 79 .9669 .9635 .9761 .9726 .9672 .9616 .9563 .9509 .9955 .9901 .9396 75 .9663 .9633 .9776 .9723 .9666 .9613 .9556 .9503 .9996 .9399 .9339 76 .9666 .9631 .9775 .9720 .9669 .9609 .9553 .9996 .9992 .9367 .9331 60 .9395 .9629 .9772 .9716 .9660 .9609 .9596 .9992 .9936 .9379 .9323 02 .9663 .9626 .9770 .9713 .9656 .9599 .9593 .9966 .9929 .9372 .9316 69 .9662 .9629 .9767 .9710 .9652 .9595 .9537 .9960 .9923 .9365 .9306 Approximate percent or ethanol required (by volume) 6 ll I6 21 26 30 39 38 91 99 #7 BIOGRAPHY The author was born in Pinckney, Michigan, August 13, 1934. He was raised on his father's farm at Gregory, Michigan, and learned about agriculture at an early age. His father was an "early adopter" of new farm equipment and practices. As an example, he purchased the first live power-take-off tractor, power hay rake, and roll hay baler in the area. The same local equipment dealer sold us a silo unloader which was the first of that brand to be installed in the state of Michigan. This type of early machinery experience brought about the author's ultimate desire for future training as an Agricultural Engineer. The author graduated from Stockbridge High School in June, 1952, and farmed with his father on the family 420- acre livestock and grain farm. He attended an 8-week Agricultural Engineering Short Course at Michigan State College during winter term 1953. He returned to the farm and stayed until September 1956, when he entered Michigan State University. Upon graduation in December 1960 with a B.S. degree in Agricultural Engineering, he moved to the Minneapolis, Minnesota, area to work for Farmhand, Inc. at HOpkins. During his 2-1/2 years with Farmhand 102 103 he worked on the design of forage boxes, manure spreaders and portable grinder-mixers. In July 1963 he moved to Milford, Indiana, to work for Chore-time Equipment, Inc., manufacturers of auto- matic poultry feeding equipment. He designed an auto- matic controlled hog feeder system utilizing the company's centerless auger. He was granted a U.S., British, German and French patent on the design. In August, 1966, the author joined his present employer, the Fruit and Vegetable harvesting group of the Agricultural Research Service, United States Department of Agriculture at Lake Alfred, Florida. During his 3 years' work in Florida, he designed a citrus pick-up machine to pick up fruit removed with a tree shaker. In July, 1969, he was transferred to his present research location at the Agricultural Engineering Depart- ment, Michigan State University, East Lansing, Michigan. His responsibilities have been the mechanization of the harvesting and handling of cucumbers and grapes. He is married to the former Patricia Jean Cochran, and they have two children: Brenda Joy and Todd Edson. ”'Cfit'l‘mflm flit M: I] @1111, W Mimi“