"‘-"Jc~. ‘.~-u- . I III III I I 146 110 __THS THE INSTITUTION USE OF QUICK FROZEN FRUITS AND VEGETABLES THESIS FOR THE DEGREE 0F II. S. Eunice C. Winans I932 ‘_9€‘e f. " K v-...ll‘ :MIIIJIIJv r . . VIII-'u‘. I b (£103.04? ,..\. Til.\ov v _ ..I o . .. . Huff. . .2“. .....,n H...h...o.... . .1... A..,£I{mr.,nwmfiwfifiI . .1 .. . ,... ,. 1. . : : 2.1.2,... : 4. . I I m . I r’.’ If! .. 11.0.“-.. 4. . .5 4 . . , . 1......‘392 a, .. . . . u . "'H“ -.'~',-,ir, ,., “I ' " - :p‘ ' I ‘olvgittt .‘e‘ .. I .I’.“g'l ‘. Q ‘ '. (0' VV m". , ~ H “:11.“ . '£ ' 'z '3 J. '. .‘pl.’ “'JJIfi-C.‘ 1MB " 94.- ;‘l‘- ’.f_‘. ~ '3‘" fl. ‘._‘:'“.“. ‘3” ,r.' . - .iyfiwI 1 "k‘ ’ql‘“ 4| ‘J v «a: . ‘ ‘ we“ ; J i , . rd A w v ‘3 I f?! ,4 & V ' I ‘ ‘6'; _ . ' . fad-J? ‘ . "j‘ “$333: w it.‘ -ty‘li‘u‘)‘ {'33 «a» . ,. ‘ ‘ "' u‘l .- , v ' ~ . ‘h - N; u . d «r» In ‘I I a his _., .- : .. ' . fit a I In "’ ”KS (0", .‘ Q I .fiju 4‘ F‘) vi! ‘. .' ‘a‘I‘I ' ' u E‘ Riv] '! I I]. n l ‘1 . u n . I l A . V O n I I ' I» u .-‘. -.;_ v . .1 “ ‘ o " . I.) ' - . I I 1’ I.'I‘ IJ.‘ ._. . . n, - . _‘ ‘ . ‘1 .l i v-, ‘ ' I I)- :_ | \ g "I Q . , Y . ‘ 1 -' ‘. I v . . l I ‘n ' ‘ ,1! J l ‘ . . . . I. u I " I ‘ ".0 '1. -_~ . _ I. r , I . ‘ - . "I“, o ., ‘ ) .u ' ' "w L 4 ,‘ . ‘.‘ a ' ' I .‘ . .' .- ‘ 59‘ 'fi.‘ ‘2'; ‘.' 0‘ N. O A" ,I' d , ‘ . l n . .'._ *4 .‘U"‘. . . J. ‘ ; :7 :1 I '41. . 't . .‘ L‘ f In .1; 3 3’" I 7. 5.5- Ta 0 5 5’ L 1.3%”. d 1-: - 1 a éfiy‘£& ‘Eyfifigfim - I '. ' ‘.-\; ,'. "-1.. I '. «a «M . am: a? I w w I» w 1-3 - -. '4 ' ' ‘91:} .1, y.‘ 'o'. . ‘ ‘ ‘us .'¥§ K; “v . . ., "I '5‘ «If 03* a? . - ‘ R l. : I" ‘ ; I C -..’.‘1 I; 4 ,~; ‘7' ‘vv. E . ‘ ’ . ' " . a . 4. f 2 0- , -- - .'.1~',,( 91“. A k ’ I“ I (3"!"‘~ ‘ . I .- J \— 0’ *'9‘ax " “ ' ‘-.. u'l _ - "‘f> , _—. _ ..", _'.%,§\m“-. .i._ L “Wrb'vn I, , a‘ ‘7'?” II ~ _.> . FT,» -‘.'_._ ' - o . . 3);. \- . j.’ 3.4; 1;"; "'2‘- ‘ f; ‘kiz'flr' V) a; . "' — fly"- .‘ .. ‘ t» ;~ ‘30 . . “gt“; 9351:? l' \‘ L‘ JIJ‘.*‘: . . I ‘ {'V”_Q'neb‘l . ' ‘4'; L In LI ., ._ . cf.” ,, .54.. :aT ' v \ THE INSTITUTION USE OF QUICK FROZEN FRUITS AND VEGETABLES BY Eunice C. Winens M Submitted in partial fulfillment of the requirements for the degree of Master of Science Department of Institution Economics Division of Home Economics Michigan State College 1932 THESIS Acknowledgements The writer is grateful to Mrs. Nabelle Ehlers and Dr. Marie Dye for advice and suggestions given throughout this study, and for their criticisms and corrections of this manuscript. To Dr. D- E. Devereux the writer is indebted for-directing the bacteriological work and for aid in preparing the report of the experiments. Acknowledgement is made to Mrs. Nbbelle Ehlers, Miss Katherine Hart, and Miss Vera Howard for acting as judges in the palatability study. 10%11‘3 The Institution Use of Quick-Frozen Fruits and Vegetables. Table of Contents Page I. Introduction............................ ..... ................ 1 A. Purpose of Study............ ..... ..................... l B. General Aspects of the iuick-Frozen Products.......... 4 0. Review of Literature.................................. 20 II. Data and Discussion.......................................... 23 A. Nature of the Foods Studied................ ....... .... 23 B. Palatability.......................................... 29 c. Cost in Central Michigan............... ..... .......... 56 D. Bacterioloaical Growth After Thawing.................. 45 E. Availability in Central Richigan........ ......... ..... 51 III. Conclusion and Summary........ ....... . ..... ......... ...... .. 53 Iv. BibliogruphyoooooooouoooooooooooooooooooooooooooooooaOoooooo 55 Tables No. Page ¢ I. Fruits Adaptable to Freezing.............................. 18 ,. II. Vegetables Adaptable to Freezing.......................... 19 III. variety, Source, Style, and Grade of the Experimental PrOductSOOOOOOOI0.000000000000000.00.000.000.000... 25 IV. Palatability Score Sheet.................................. 31 v. Average Scores for Palatability........................... 32 VI. The average, Minimum, and Faximum Palatability Scores..... 55 VII. Rating of the Foods by qualities and Total Scores......... 34 VIII. Rating of Foods in Group A for Palatability............... 54 IX. Rating of Foods in Group B for Palatability............... 35 X. Cookimg~ Time Required. .. ............ . ........ ........ . . 38 XI. Essential Factors Used in Computing the Cost of the PrOdUCtS am the Final COSt-ooo-onoooococoooooooooo 39 XII. Average Cost of Each Class of Product..................... 41 XIII. Average Prices for Fruits................................. 42 XIV. Average Prices for Vegetables............................. 43 XV. Cost Levels of the Products in Group.A by Classes......... 44 XVI. Cost Levels of the Products in Group B by Classes......... 45 ./ XVII. Growth of Bacteria in auick-Frozen Fruits and Vegetables After Tha‘v1n2000000 oooooooo 0000.0000000000000000000 48 THE INSTITUTION USE OF QUICK-FROZEN FRUITS AND VEGETABLES I. Introduction Considerable interest has been manifested in quick-frozen food products during the past few years. It is apparent that these foods are beginning to find their sphere of usefulness, and it is time to distinguish between the mere novelty of the new development and its practical appeal. The novelty of these frozen foods has brought about a certain amount of spectacular publicity. However, the ultimate test is always the question of how much better the new method serves our needs than those in use at the present time. The use of quick-frozen foods in institutions is increasing, but results have not been unfailingly successful. Out of the limited selection of quick-frozen meats, fish, fruits, and vegetables offered the institution buyer by manufacturers and distributors, quick-frozen meats and fish seem to have stood the test of time with a certain de- gree of success. But the newer members of the quick-frozen family, fruits and vegetables, are still on probation. The lack of adequate information concerning the nature and use of these fruits and vegeta- bles suggested the present study. The field was too large to study in total so this investiga- tion was confined to certain definite properties common to quick- frozen fruits and to quick-frozen vegetables. Five different aspects of the products were chosen for study: A. The nature of the quick-frozen products per se. B. The relative palatability of the quick-frozen products as compared with corresponding canned and fresh products. C. The cost relationship of quick-frozen, canned, and fresh fruits and vegetables in central Michigan. D. The extent of bacteriological growth in quick-frozen pro- ducts after they have thawed. E. The availability of quick-frozen fruits and vegetables in central Michigan. Because of the recent advent of these quick-frozen foods on the market, it was deemed advisable to include considerable introduc- tory material in the thesis. The definition of certain terms commonly used in the quick-frozen industry, the historical background of the industry, and the principles of freezing the fruits and vegetables are briefly treated in an effort to gain clarity. An attempt was made to keep the conditions under which the study was carried on as nearly like those in the average institution as possible. All of the foods used were of the nature commonly en- countered in such places. The quick-frozen fruits and vegetables, with one exception, were obtained from a firm in Chicago who special- ize in the needs of institutions. The canned goods came from the store room.of the Women's Commons on the campus of Michigan State College. In the kitchen of this institution many of the examinations were made. The canned goods were of no special brand but varied con- siderably in brand as is the usual situation in store rooms. The examinations were made at a time when fresh fruits and vegetables were out of season. However, it was possible to get a few fresh products, so whenever they were available, the fresh flrods were examined also. Upon first examining the products the color, size, shape, and flavor were noted and recorded. The procedure then followed, and the information obtained is indicated by the steps below. 1. Weight E. P. (Later found not to be essential to the pro- blem) I 2. Measure E. P. 3. Time required for certain preparation processes. 4. Namber of servings. 5. Samples taken for bacteriological examination (for frozen fruits only). The foods were all prepared for table use. The same kind of food from the three classes, frozen, canned, and fresh, were prepared by the same method allowing for individual differences. A variety of methods was used in the study. Pies, sauces, shortcakes, and salads were made of the fruits. The vegetables were all cooked in water and then seasoned and buttered. The foods were then submitted to the Judges to be rated according to palatability. The cost study is based on the costs involved in the use of the experimental products. This method limits the importance of the results somewhat, but the relationship of the costs of the frozen, canned, and fresh products should be indicated. Hewever, the prices of canned goods are known to be quite stable, and from all indications the prices of the quick-frozen foods are following suite. Consequent— ly, the prices of the fresh products are the most unstable and probably constitute the weakest factor in this phase of the study. For the bacteriological examinations, samples of the frozen fruits and vegetables were taken to the laboratory of the Bacteriology Department on the campus. The availability study embodies a survey of the distributing agencies operating in central Michigan. B. General Aspects of the Frozen Products. Freezing Terms. The terms used in the frozen foods industry are still somewhat vague due to the youth of the enterprise. Cold pack, frosted, quick frozen, slow frozen, sharp frozen, frozen pack, and instant frozen are terms used in describing the foods and often lead to confusion unless they are clearly defined. Woodroogfgives good definitions of most of the terms now used in commercial practice. .§l2!_££22EEEE.iS the method of freezing which makes use of a temperature ranging from the freezing point of the product to zero degrees Fahrenheit. This is the method used in all of the experimen- tal packs of fruits until a few years ago. Sharp freezing is the term applied to freezing at a tempera- ture ranging fran zero to —lO° F. Freezing at this temperature is much more rapid and produces a better product than slow freezing. Quick freezing_refers to a temperature below -100 F. It arrests spoilage even better than sharp freezing and increases the out- put of a plant within a given time. Instant freezing is a term being introduced by the Crystal Car- bonic Laboratory, Where a temperature ranging from -80° to -100° F. is used. Freezing at such a temperature may produce a product superior to any other system of freezing. Cold pack refers to packing prepared foods for freezing. lgrozen pack_refers to putting frozen food in containers or wrappers. _Frosted foods is a term being introduced by the General Foods Corporation for their quick frozen products. Defrosting refers to the act of removing cold from a product. Complete defrosting is accomplished when all of the ice crystals have been removed. Historical Background. The effects of freezing upon plant and animal tissues were probably observed by man fer centuries before the usefulness of these phenomena in his daily life came to be realized. The practical utili- zation of refrigeration in connection with foodstuffs began in histo- rical times with the use of atmospheric low temperatures, ice, and snow for the cooling of foods and drinks to temperatures that make them more palatable and retard deterioration and the development of organisms causing spoilage. Not only are low temperatures and ice nature's oldest preservatives, but they have also been highly success- ful as shown by the finding of well preserved specimens of prehis- toric animals in the northern ice by scientists after thousands of years. Although the Chinese have for hundreds of years frozen by natural means for the purpose of transportation the very juicy and very perishable Kaki type of persimmon (38) and although the Greeks and Romans were thoroughly acquainted with the preserving action of cold (20), it is a strange fact that the commercial application of -5- this principle did not begin in other countries until comparatively recent times, and the freezing preservation of horticultural products is still an infant industry. Probably the greatest early stimulus to the frozen products industry came from the handlers of fish (42). Two leaders in the frozen fish industry are Clarence Birdseye and H. F. Taylor. Birdseye ,became interested in quick freezing as a result of his experiences in Laborador and other northern regions where he studied the effects of extremely low temperatures on fish. He is credited with noting that under certain conditions frozen fish when thawed out resumed the life processes. Birdseye's information became the basis for developing a system for freezing fish and meats, a system that is now being experi- mentally used in freezing plant tissue. As long ago as 1860 in Australia Morris and Mort are seen to have been the first to freeze successfully and export beef and mutton to England. Piper in Maine was a pioneer in commercial fish freezing in 1861 (20). H. F. Taylor (36) states that between 1861 and 1913 at least eighteen patents were granted on improvements in the art of freezing . fish. During that time also in scientific journals a voluminous liter- ature had accumulated relating to the chemistry, morphology, and micro- biology of freezing foods. However, there was no evidence of a con- sideration of the relation of the rate of freezing and the quality of the finished product. About 1912-13, methods of freezing fish rapidly by direct immersion in cold brine were introduced on a small commercial scale in Norway and Denmark. The period of refined applications of cold began with the end of the Great War and was initiated by and for the fisheries industry. Rapid freezing came about in fisheries to meet an economic situation. Fish are highly irregular in production, exceedingly perishable, and the greatest demand exists during the period of lowest production. The system of freezing saved the industry from a decline that had set in. In 1929 twenty-two million pounds of fish were frozen. The system has been taken up by the meat industry and today we have experimentation or selling going on in many firms. General Foods Company with their ”Birdseye Frosted Foods" in Springfield, Mass., Swift and Company in Chicago with their identifiable cuts, the Indian- apolis Abbatoir with ”Sally Lee” products, and Cudahy Brothers of Wis- consin are some of the outstanding firms. With these and many such firms the industry seems to be gaining and to be on a stable basis. Horticulturalists and plant physiologists have been observing the effects of preservation by freezing as a commercial practice on the quality of fruits and vegetables for more than thirty years, but due to the fact that freezing kills tissue, causes cell leakage, and destroys turgidity, freezing has long been considered a thing to be avoided. Thus it has been somewhat against prejudice that the pro- ject has been developed (44). For many years the preservation of plant tissues by subjecting them to very low temperatures was regarded only with academic interest. A few scattered instances of its use are recorded. It has been re- ported that fruits were frozen for several years prior to 1912 in the first Statler Hotel to supply berries for the winter trade. Subse- quently, berries were frozen to be served on the Northern Pacific Dining -8- Cars (19). Sexton and Company of Chicago report that they have used frozen fruits in their jam kitchens for years. However, the industry really had its inception about twenty- four years ago in the Pacific Northwest. Fulton (21), Baker (1), and Culpepper (10) describe some of the conditions and results of early experiments in freezing berries and peaches. State experiment stations in at least two widely different growing regions early approved freez- ing as a method of preserving fruits. These stations were Michigan in 1917 (32) and California in 1919 (s) and 1920 (9). Berry fruits were packed experimentally in the Pacific Northwest as early as l912,but no commercial packs were made until 1918 (20). Success in these fruits led to investigations in other fruits and also in vegetables. Georgia entered the frozen fruit field experimentally in 1925 and commercially in 1930 (42). Kidd and West (28) in Great Britain (1925-26) satis— factorily preserved peas, asparagus, and cauliflower. Originally freezing was a means of disposing the surplus fruit. As the industry grew, produce was grown especially for freezing and only the choicest fruit was used. The very juicy and very perishable Georgia peach was found in 1929 to withstand freezing successfully (38). The preservation of cherries by quick freezing in Wisconsin, begun in 1925, feund its value in providing an orderly and economical method of marketing the surplus product. Incidently, no other method of preser- vation produces cherries so like the fresh ones as the quick—freezing method (39). It can still be said that the bulk of quick-frozen fruits is packed for the wholesale or remanufacturing trade, confectioners, preservers, pie bakers, syrup manufacturers, and ice cream makers, but in the past three or four years production and marketing in the retail container has been developed considerably (37). The field for the quick—freezing of vegetables is mudalnore limited than that of fruits. The institution trade consisting of restaurants, hotels, caterers, and other institutions, and the retail trade comprise its sphere. The development of this class of frozen foods has been within the last four years and is carried on in a much smaller scale than for fruits. At present the industry is in a stage of flux and experimentation. The magnitude of the frozen fruit and vegetable industry can be shown somewhat by estimates of the packs of some of the most impor- tant products during recent years. Ullspergsr (39) stated that approximately one hundred.million pounds of fruit are packed annually. D. Taylor (37) made the statement that in the past decade and a half cold packing of fruits in the Pacific Northwest has grown from.a1most nothing to an industry with an annual output valued at wholesale at $5,000,000 or more. One plant alone in Georgia packed seven hundred thousand pounds of peaches in 1930 (38). In the same year the frozen pack of cherries by one organization in Wisconsin was eight million pounds (39). Figures on the frozen vegetable pack were not available, but the trend is the same as for fruits only on a much smaller scale. Distributors report increasing activity in the frozen fruit and vegetable line. John Sexton and Company, Chicago, wholesale dis- tributors, assert that their sales per year have reached thirty car loads. In the retail distributing field the General Foods Corporation -10- has taken the lead. One hundred different types of meats, fish, vege— tables, and berries are packed and put on the market under the name of "Birdseye Frosted Foods" (17). They further claim that two hundred retail stores are selling these products and are located in the eastern states, chiefly in New England. The question of the present status of the industry wauld not be completely considered without some estimate of the demand factor. Bird- seye (3), Ullsperger (39), Tucker (38), and H. Taylor (35) show that. the demand is unquestionably increasing. Ullsperger (39) asserts that all the large markets in the United States are using large quantities of Wisconsin cherries each year-~Chicago ten to fifteen thousand bar- rels, Philadelphia twenty-five thousand barrels, New York fifteen to twenty thousand, with smaller cities such as Indianapolis, St. Louis, Columbus, and Cincinnati using from five to ten thousand barrels. The Hotel Monthly Magazine (18) reports that frozen fruits find favor in hotels and restaurants. Food experts (15) (6) in popular women's magazines point out the interest and acclaimation of the public- The very fact that state experiment stations are spending time and effort in the study of quality factors involved in freezing fruits and vegetables points to the importance to the public. At the Frozen Pack Laboratory (14) of the Bureau of Plant Industry, United States Department of Agriculture, at Seattle, washington, a wide range of horticultural products totaling nearly thirty thousand small containers have been prepared and examined. At the Georgia Experiment Station (43) twenty-five kinds and seventy-one varieties of fruits and vegetables -11- have been studied. Several manufacturing concerns maintain research laboratories also. More of such work seems particularly essential at present when many technical problems are yet imperfectly understood. Principles of Freezing Plant Foods. At present there is some difficulty explaining how freezing is so destructive under some conditions and has such marked preserva- tive properties under others. Authorities are not entirely agreed upon the factors essential to the satisfactory development of quick- frozen fruits and vegetables. Hewever, they do admit that there is a much different problem with frozen plant tissue than with animal tissue. Three leaders in the experimental field, Diehl (12), (13), (14), Birdseye (3) (4), and Woodroof (42) (44), emphasize the close relation- ship between the horticultural character, varietal peculiarity, matur- ity of the raw materials, and the quality of the finished product. Not all varieties of the same fruit or vegetable are equally good for quick freezing, nor are the same varieties grown in different parts of the country of like value. It seems that truck garden varieties usual- ly are more desirable than those found suitable for the canning indus- try. The maturity of raw material is also a matter of primary impor- tance. Experimentation on each class and variety of fruit and vege— table is required to detenmine the specific degree of maturity which produces the most successful product. As a rule their maturity should be comparable to that required if they were to be eaten fresh from the .garden. The ultimate choice of raw material should be based upon a composite of several factors of production, adaptability, quality, and cost. -12.. The preparation of the products for freezing requires much care. All of the products are cleaned and graded, and much care is exercised in handling them. Special treatment is given many products as well. It has been found that blanching is desirable for almost all vegetables although some of them apparently do not require it for the preservation of color and flavor. Other advantages of blanching are that it tends markedly to reduce the population of microorganisms which are naturally present on all vegetables, and that with leafy vegetables the wilting produced aids in packing since it reduces the volume. The addition of extraneous materials has been found to lessen the damage of quick freezing fer many fruits. Diehl reports that almost all the fruits that he has tested give the best results when they are prepared with sirup of a concentration depending upon the nature of the fruit, particularly as to acidity. Joslyn and Cruess (27), Joslyn (25) (26), Diehl (14), and hoodroof (42) (44) have found that a more satisfactory product is obtained when syrup rather than dry sugar is used. Birdseye has obtained successful results without the addition of sugar through his freezing method which requires a very low temperature. The addition of citric acid to a few of the fruits such as peaches and white cherries helps to solve the problem of oxi- dation. Diehl is in favor of adding brine to many vegetables prior to packing since it helps protect the product from direct exposure to the atmosphere. Many factors affect the choice of container. The two most popular types are the paper board box and the tin can. Each one has -15- its particular advantages and disadvantages. Obviously, the freezing plant should be located at or very near the production point if the processing is to be done when condi- tions are most advantageous. Portable quick-freezing units are now being transported from one point of production to another to accom- plish this objective. There are four general classes of machines and devices for doing the quick-freezing operation. These general types of refriger- ants are as follows: 1. Direct contact or emersion in a brine, usually calcium chloride. 2. Indirect contact with a brine. 3. Cold air blast. 4. Direct or indirect contact with solid carbon dioxide. It is too early in the life of the process to say much about the rela- tive value of these refrigerants. As general commercial practice for fruits and vegetables at the present time, cooling and freezing at a temperature centering about zero degrees Fahrenheit seem to be commonly accepted and based on the best information available. However, the range may go down as far as fifty degrees below zero Fahrenheit. Low temperatures are more success- ful as a preservative than any other single agent tried. Birdseye (4), Woodroof (43), and Diehl (12) all adhere to that theory, and there is a growing tendency to freeze at a lower tenperature than formerly. Wood- roof believes that a drop of ten degrees in the temperature in a range of moderate temperatures above zero degrees F. is more effective than -14- is a similar drop in a range of very low temperatures or below -50° F. The fact that living tissue frozen at a temperature just below the freezing point is more broken down after defrosting than a similar tissue frozen at -50° F. is known to scientists. Just how this destruc- tion is produced is not agreed upon. Birdseye (3) (4) claims that it is the relative size of crystals that produces different effects upon the tissue--the slower the freezing the larger the crystals and conse- quently the more the destruction on thawing. 0n the other hand, the cell walls of vegetable matter are composed of inelastic cellulose and are therefore sure to be broken by the mere expansion of moisture whether the freezing is slow or fast. Taylor (34) (35), Fellers (20), Diehl (12), (13), (14), Joslyn (25) (26), and Woodroof (42) (44) adhere to the following theory. Ice crystallization in plant tissues ordinarily begins not within the ~ cells themselves but in the intercellular spaces, where the ice cry- stals may grow further in size through crystallization of water without drawing frcm.the living protoplasm of the cells. This process may con-F tinue until cell shapes are pressed and distorted by ice masses, and in rapid freezing at very low temperatures there may eventually occur a rupturing of the cell walls. Inherently, however, the freezing of plant tissues is really a drying phenomenon, due to the more or less rapid withdrawal of water from the cell contents to the crystallization foci in the intercellular spaces. The physiological character of these cell contents may be irretrisvably altered so that the living material of which they are composed takes on a changed permeability to tissue juices, and leaking -15- of the latter occurs. The cell contents consist of a colloidal gel con- taining proteins, salts, and water. When the bound water of the colloi- dal complex is withdrawn on freezing, the gel structure is broken down. This reaction in plants is irreversable, so that after thawing the water is not reabsorbed and the fruits and vegetables lose their turgi- dity and original firm structure. Some of the tissues or portions of them may eventually die as a result of the changes brought about by freezing and undergo chemical decomposition. In all this the piercing of cell walls and mass crushing of protoplasmic materials by growing ice crystals probably plays a less important role than is popularly supposed. There are varying degrees of injury caused by freezing based upon the capacity of the material to be restored after thawing. In most cases death to the cells is produced. Freezing to death may be defined as injury by freezing, involving the disorganization of the substances essential for carrying on the life processes in the organ— ism. ( Chemical activities brought about through the influence of enzymes is inhibited by freezing but not destroyed. On the thawing of the foods the deterioration proceeds rapidly, in some cases much more rapidly than before freezing, and manifests itself both in the color and flavor of the product. Oxidation of the products, due to the activity of the enzyme oxidase, is one of the most diffieilt pro- blems of the industry. The use of very low temperatures, sirups, brines, blanching, etc. seem to offer some hepe of meeting this pro- blem successfully. In addition, respiration processes that result -16- in the loss of fresh flavor, aroma, and color may not be prevented by freezing. For a full discussion of the effect of freezing plant tissue, see Taylor (34), Birdseye (3), Woodroof (42), (43), (44), Magoon (30), Joslyn (26), and Diehl (12). At no time during the whole process of freezing, storing, or transporting is one out of the danger of damage resulting from the temperatures going up. A failure to keep the proper temperature renders useless all of the operations that have gone before; and no amount of subsequent care will counteract the damage done. It has not yet been detennined definitely at just what temperature or under what conditions fruit is rendered worthless by accidental or temporary defrosting. The following temperatures are recommended fer the stor- age of fruits and vegetables: Woodroof (42) recommends 8° to 14° F. Theiss* (John Sexton & Co.) recommends 0° to 10° F. Ullsperger (39) (for cherries) " 5° to 10° F. Birdseye (3) (4) " --200 to 5° F. At any rate it is agreed that a fluctuation of storage temperatures seriously affects the quality of the foods. J. ‘ As for the nutritive value of frozen fruits and vegetables, there seems to be little definite data. Fellers (20) believes that freezing per so has very little effect on the nutritive properties. Collateral facts and studies lead strongly to this conclusion. Wood- roof (44), Taylor (34), and Diehl (12) report no significant changes in chemical constituents. As for the vitamin content, the freezing *Interview with Mr. M. H. lheiss of John Sexton Co., Chicago. )0] th -17- process does not seen to harm it, but the effect of long storage is somewhat questioned (ll), (40), (15), (5), (23). Practically no studies of the care of the frozen products by the consumer have been made. Hewever, the effect of handling the pro- ducts have been observed and the following advice is given. Ireland (22) believes that the best results with bulk fruits were obtained when they were defrosted in the original containers without exposing to the air; Eddy (15) recommends thawing the foods in the refrigerator; Woodroof (43) found that defrosting at room temperature an hour or so left the products in an excellent condition. Diehl (14) said that for vegetables which have to be cooked, rapid thawing with the con- tainer immersed in water about room temperature involved no signifi- cant deterioration of the product. Emphasis was made that the frozen food be treated like perishables and used promptly upon thawing, since any slightest thawing or even approach to it is fatal to the quality of the food. The extent of the adaptability of fruit and vegetable products to the freezing method of preservation indicates the future possibili- ties of the industry. Tables I and II list the fruits and vegetables that are said to be adapted to the process and indicate the authority. ~18- Table I- Fruits Adaptable to Freezing. No.( Fruit Diehl (12).Woodroof (44).Joslyn (26))Birdseye (3) U.S.D.A. Ga. Cal. 1 apples + + 4 2 apricots & 4 3 avocados + + 4 bananas 4 5 blackberries + + + + 6 blueberries + 4 7 cantaloupe i 4 ' 4 > 8 cherries + 4 4 9 cranberries + 10 currants ll dewberries + 12 figs 4 + 13 grapes + 4. 14 grapefruit 15 gooseberries + + 16 huckleberries + 4 17 loganberries + + + 18 peaches + + + 19 pears 4 4 20 persimmons + 4 21 pineapple + 4 22 plums + 4 4 4 (It 0 Prune) 23 raspberries + r + 4 24 rhubarb + + 25 strawberries + + + + 26 watermelon + + -19- Table II. vegetables Adaptable to Freezing. No.‘ vegetables Diehl (12)‘Woodroof (44)(Joslyn (26)(Birdssye (4) U.S.D.A. Ga. Cal. 1 artichokes + e 2 asparagus 1 4 + 3 brussel sprouts + 4 carrots + L 5 cauliflower + 6 corn ‘ + 4 + 7 ‘ Italian Broccoli + ‘ 8 kale + 9 lima beans + ‘ + 10 parsnips + 11 peas + + + 12 spinach + + + 13 string beans 4 + 14 wax beans + Vegetables that are said not to be well adapted to preserva- tion by freezing are tomatoes, celery, lettuce, cucumbers, radishes, and egg plant. -20- C. Review of Literature. There is very little information available on the use of quick frozen fruits and vegetables by the consumer. Woodroof (42) and Diehl (14) recommend using them as the corresponding fresh ones are used. Collateral material concerning factors which influence the use of the products has been found reported in scientific, trade, and business Journals, as well as official publications. In the first place, the feasibility of freezing a wide range of fruits and vegetables has been proved by the investigations of Diehl (12) (14); H. F. Taylor (35) (36);_Woodroof (42), (43), (44); Joslyn (26); Joslyn and Cruess (27); Birdseye (3) (4); The British Food Industrial Board (7); the Council of Scientific and Industrial Research in Australia (31); The Low Temperature Experiment Station (29), Cambridge, England; Magoon (30); Fellers (20); and Wiegand (41). Diehl (l3) (l4), Joslyn and Cruess (27), Birdseye (3) (4), Wood- roof (42), H. F. Taylor (36), Tucker (38), and Rhodes* clahmed that certain frozen products are successfully preserved both in color and flavor. Megoon (30) considered that with a few exceptions the flavor and aroma was unnatural in the products. Woodroof (43) reported only slight traces of this condition. Eddy (15), Diehl (l4), and Birdseye (4) claimed that, due to the fact that nest of the products are frozen at the point of pro— duction within a few hours of harvest, the frozen horticultural pro- ducts reach the consumer considerably fresher than much of the fruits *In a recent communication from T. Cecil Rhodes, director of medical Arts Laboratory, Jenkintown, Pa., he states that frozen peaches were found to have all the original properties of the fresh fruit. -31- and vegetables offered on city markets. Leaders in the commercial field give us some indication of the net cost of the frozen plant foods. Birdseye (3) claimed that the cost of the frozen products is lower than that of the corresponding fresh food, particularly if out-of-season demands are to be met. He further stated that, due to added convenience in the cleanliness and completely edible form of the products, prices above those of the fresh products have been proved economically justifiable. Tucker (38) re- ported that the price of frozen Georgia peaches was the same as the fresh peaches on the New York market. Ullsperger (39) said that the cost of frozen cherries is greater than canned but less than fresh cherries in crates. Birdseye (4) and Woodroof (44) believed that the actual cost of the frozen products was reduced by the fact that freezing had the same effect on the tissues as far as tenderness is concerned, and therefore the cooking time required is reduced. Also the elimination of practically all waste from the frozen foods at the point of pro- duction lowered the actual cost. What work has been done on the microbial growth in frozen foods has been done very recently. Fellers (20) gave the best review of the subject. Birdseye (3), Diehl (14), and Magoon (30) believed that the original bacteria content of fresh foods is reduced by freez- ing. Prescott et a1 (33) and Diehl (14) found that the reduction of bacteria content increases with the length of the storage time. The work of James (25) indicated that the spores of clostridium botulinum (type B) are inactivated by freezing but not killed. Berry claimed -22.. that he has never with certainty recovered clostridium botulinum from frozen vegetables upon long storage after thawing or even when the vegetables have been previously inoculated with the spores. Fellers (20) reported that the examination of seventeen sam- ples of frozen fruits and vegetables reveal that the microbial growth is slower in fruits than in vegetables and that the varieties of bac- teria are relatively few, and that vegetables, particularly, are made less resistant to bacteria by freezing. Publications from the Frozen Pack Laboratory of the United States Department of Agriculture (12) and from the State Ekperiment Stations of California (26) and Georgia (44) list the fruits and vege- tables which are adapted to the freezing process of preservation. -23- A. The Nature of the Foods Studied. Altogether, twenty-four different quick-frozen plant foods were examined; fourteen kinds of fruits and five kinds of vegetables. Two of the vegetables, asparagus and spinach, were not reported since they are not on the market due to imperfect quality and the danger of the development of the poisonous botulinus toxin. The regular insti- tution packs of eight and one half, ten, and sixteen pounds, expressed from Chicago, arrived in good condition, being solidly frozen even after approximately twenty-four hours out of refrigerated storage. They were packed in corrugated fiber-board shipping cases supplied with additional insulation by pads or liners. Upon delivery the cases were placed in refrigerated rooms. The temperature of the particular room.in Which they were placed de- pended upon whether the use was to be immediate or delayed. Immediate use meant within twenty—four to thirty—six hours, and delayed use meant at a time more than thirty-six hours after delivery. For immedi- ate use the products were placed in a room in which a temperature be- tween forty to fifty degrees F. was maintained. This temperature allowed the products to thaw gradually. At the end of thirty-six hours few ice crystals remained in the foods. The refrigerator in which the foods for delayed consumption were placed maintained a tem- perature of approximately -100 Fahrenheit and did not permit the pro— ducts to thaw. These products, due to the low storage temperature, required a longer time for thawing. The fancy grade of canned fruits and vegetables were selected as being the ones which would most nearly approximate the grade of the -24- quick-frozen products. A corresponding canned sample was tested for each quick-frozen food except for blackberries and red currents, which were not on hand. The brands of the canned food varied, as they do in the average institution store room. The size of the can was number ten, except for the grape fruit which was number five. In every case when the fresh products were available, they were purchased from.wholesale distributors and examined also. Green peas, strawberries, rhubarb, grape fruit, and apples were so used. much information concerning the foods used is shown in Table III. The information concerning the variety of the product and the region in which it was produced was obtained from the distributors of the foods. In some instances such information was not available. The style and grade of the products are also indicated for the commodities which exhibit those factors. -25- Table III. variety, Source, Style, and Grade of the Emperimental Products. Name . variety . Region of Style Grade Production s--with sugar? Apples frozen Winesap wash. 3, sliced Fancy solid pack canned Baldwin New York sliced Fancy ' solid pack fresh Wagner .Mich. Orchard ..-- Run Apricots frozen Moorpark Calif. halves with Fancy skins on canned Moorpark Calif. halves with Fancy skins off Blackberries Evergreen frozen or wash. 3 Fancy Lawton canned oEvergreen 30:00am .8wa Iv»-.-...9|.LT.|---.. wiiuLalzll. noom 3080nfifl .Hoom 93> noom 0.30302 0000 0006 93> ”50.3085 .830 smug H0309. swabs fiofionflfl @509. fig nwsoa . .3333 . 330.300: . H0309 j902—09 knob a 003.3209 00.300 00.300 05h 008000 30> 00.260 3090.800: .3233 03m 055 be» haoaonvufl 0.5339 05900.5: noom 3080.3“ .Hoom snob . noom . 0.30302 coon . 05909394 . 30> . 023.3394 a m n a. m c m. 3,309.3 033. 090a nonvonm poosm onoom suaaflpapuaum .bH 0.309 Table V0 Average Scores for Palate bility a - High Score - 55 b - High Score - 28 i------------------j--_--------._3535551 ‘‘‘‘‘ _-.1----_ _-,....Qanned ,, , Fresh . Totals ! L W 1 “ Frozen Canned Fresh 3 Product 5 App. Tex. Ten. C. p F. App. 192:-j.?EQL-.C E‘_; App. Tex. Ten. C. F. a. b. a. b. a. b. 55555555:::::::11-35:5:6 5.27.55. 5 55.555.545.45. ..-..5;5_. 5.55. 5.55. 5.55 5.55 5. 5 2555 5 55.5. 5 555 5 2 apricots ; 6.2 6. 6.75 7. ..1.§:5 *6.75 6.5 T 6.62 6.5 6.5 not available 52.5 52.7 5 Blackberries “j§ 6185 6.5, 6.85 7. 6.75 not available 5 n ‘ 54. 4 Blueberries j_,z.amm~362. 6.5 7 7. 6.75 5. 5 '1 6. 5.5 5.26 55 55 55. 27. 5 Red Cherries 5 7. 6.75 6.125_ 7. 7. 5 5.75] 6.5 5. 4.87 " " 35.9 27-1 ' 6-Red Currants 6.12 5.87 6.5 i 6.25 6.5;“_ - not available n n 51.1 ‘ 7 Grapefruit 7. 7. 0.62 7. 6.5 5.87 5.75 6.5 6.6 6.12 5,75[—6,g l 6.5 L 6.95f 6.5 54.1 50.7 5255 ‘ 8 Gooseberries 6.85 6.75 6.5 6.62 6.9 6.62 5.87 6.5 6.2 5.2 not available 33.7 30.4 9 Loganberries 6.5 6. 5.75 6.75 5.75 5.25 4.75 5.75 4.75 5.62 n n 30.7 26.1 10 Peaches (sliced) 6.6 _fl 5.75 6.5 6.6 6.25 6.25 5.5 6.25 6.75 5. . n . c . . 51:”“T‘ . 50. . 5 ll Peaches (halves) 6.5” 6.l2 6.12 7. 5.12 7. 6.75 6.75 6.75 5.62 n n 30.7 32,3 _ 12 Prune Plums 7. 6.75 5.75 7. 7. 4.75 5.87 7. 5.12 5.8 n n . 55.5 28.7 15 Raspberries 6.2 6.6 ‘ 6.85 6.95 5.25 5.7 5.75 6.02g, " n 26.6 22.7 14 Rhubarb (a) 6. 6.58 6.12 6.62 6. 6.57 5.82 5.62 5.87 55127 6.58 5.85 7. 7. 7. 51.1 27.5 54.2 15 Rhubarb (b)w . 6.5 5 6.5 7. _J _7. .x115557' . . 5 '7 55.57 16 Strawberries 6.58 6.45 6.55 6.7 4.62 5.62 5.75 5.5 6.5 6.7 7. 7. 25.9 19.4 27.2 1? Corn on Cob 4 7. 5'751-.7° 4.85 5.75 6 5 5.75 6.5 not available 24.6 24.4 18 Peas (a) 5.87 5.75 6.5 6.5 4.62 6.75 4.25 5.75 6.52[» 1:5- | 6.62I 6.12 25.1 _2.31'4 24.5 19 Peas (b) 6.62 6.58 6.5 5.5 - not'available ‘ 25. 20 Green Lim§_Beans 6.85 6.58 6.62 6.5 5 6 _6 4.57 4.8 " " w~ 25.5 20.8 Total 150.52 101.57 112.96 169.94 125.22 91.65 74.65 87.66 88.91 88.95 55. 26.5 525.05 54.52 55.62J250.18 150.7 520.5 108.7 100.7 51.5 Average 6.516 6.55 6.27 6.54 6.26 5.72 5.74 6.26 5.55 5-56 6.6 6.62 6.26 6.86 6.72 52.15 25.1 29.1 21.7§53.65 25.75 Tables VI, VII, VIII, and IX present the information in Table V in a somewhat different manner. Table VI shows the average scores given each of the five palatability qualities for each class of food. The maxiium and minimum scores of each quality show the range covered. Table VI. Average, Minimum, and Maximum.Palatability Scores Product Frozen Canned Fresh Scores Extremes Extremes Extremes Used Average. Average. ~ .Average( Min. max. 5 Min. Max. Min. Max. Appearance5 6.51 5.5 6.85 5.72 4.62 7. 6.6 6.58 6.75 Texture 6.33 5.75 6.75 5.74_“;gt75 6.75 6.62 6.2 6.85 Tenderness 6.27 5.62 .J§£¥1_ 6.26 5.12 :ZL. 6.26 5. 7. Color 6.54 5.62 7. 5.55 6.75 6.75 6.86__( 6.62 7. .r‘ ”wrfifll Flavor 6026 4075 70 5056 408 6038 6072 6012 70 Totals*(a) 32.15 27.51 54.1 23:11 26.1 52.7 55.65 62.7 54.2 Totals (b) 25.1 23.5 26.6 21.74 19.4 24.4 25.75 24.3 27.2 *Due to the fact that the highest possible score with some products was 55 and with others 28, all the scores could not be averaged together. Totals (a) include those with the highest possible score of 55, and totals (b) include those with the highest possible score of'28. that the trend is the same. It will be noticed Table VII shows the rating of the three classes of foods by each quality. high score, and the low score is indicated. shown for comparative purposes. shown in the same manner. The class of food receiving the highest score, the second The actual scores are also The relationship of the total scores are Table VII Rating of the Foods by Qualities and Total Scores No. Quality . Highest Score‘M’ Second High 4 Low Score 1 Appearance Fresh 1 6.6 Frozen i 6.51 Canned 4 5.72 2 Texture Fresh 6.62 Frozen 6.53 Canned 5.75 3 Tenderness . Frozenl 6.27 Fresh 6.262 Canned 6.261 4 Color Fresh 6.86 Frozen 6.54 Canned 5.55 5 Flavor Fresh 6.72 Frozen fi__§;§§ L‘_(_J_a‘_1:‘1_r1_ed 5.56 6 Total Scores 4LGroup_a) Fresh 35.63 Frozen 52.15 Canned 29.11 Tables VIII and IX show the relationship of the three classes of foods, frozen, canned, and fresh, according to the scores they re- ceived. The class that was given the highest score, the second high score, and the low score is shown respectively. Two tables were neces- sary to distinguish between the foods that were available in the frozen, canned, and fresh state and were therefore compared in groups of three (Group A), and those that were available in the frozen and canned state only and were therefore compared in groups of two (Group B). Table VIII. Rating of Foods in Group A for Palatability. No. Kind of Food 1 Highest Score 4 Second High Score Low SZenET 1 Apples Fresh Canned Frozen‘ 2 Grapefruit Frozen Fresh Canned 3 Peas ‘ Frozen ‘ Fresh ‘___mmfi_”9anned__~ 4 Rhubarb Fresh Frozen _ --53?EE§L..I 5 Strawberries Fresh Frozen Canned ' *The low score for apples can probably be explained largely by the fact that a variety was used which does not freeze well- -35- Table IX. Rating of Foods in Group B No. i Kind of Food 1 High Score i Low Score 1 Apricots Canned Frozen 2 Blueberries Frozen_fi Canned 3 Red Cherries Frozen Canned 4 Gooseberries.‘”fl Frozen Canned 5 Logan berries Frozen Canned 6 Peaches (sliced) Canned Frozen 7 Peaches (halves) Frozen Canned 8 Prune Plums Frozen Canned 9 Raspberries Frozen Canned_ 10 Corn on the Cob___._;Erg§en Canned ll Lima Beans Frozen __ “Canned In general, there seems sufficient indication from our examin- ations to conclude that quick-frozen fruits and vegetables rank high in palatability. As ccnpared with the fresh products, the quick- frozen products stand out very favorably in appearance and color. For tenderness the frozen foods are preferred to the fresh, since the effect of freezing foods in respect to tenderness is similar to that of cooking them. In flavor and texture the frozen products are rated second to the fresh products but decidedly superior to the canned pro- ducts. There can be little doubt that, as far as palatability is con— cerned, the frozen products are preferable to the canned. Since the production of quick-frozen plant foods is still in the experimental stage, it is fair to expect nuch variation in the pro- ducts. Diehl (15), Woodroof (44), and Joslyn, who are doing extensive scientific work in the field at present, are of the opinion that as the technique of freezing improves more of the natural attributes of -35- quality will be retained in the products. It is possible that in cases Where frozen foods compete with out-of-season fresh products they will even be preferred to the fresh products. Co The Cost in Central Michigan. In computing the actual cost of food in an institution it is necessary to include the cost of several different factors. But since the object of this price study is to find only the relative level of the cost of the quick-frozen fruits and vegetables as compared with the level of the prices of the corresponding fresh and canned products, only the major factors contributing to the cost were considered. The principal factor is, of course, the market price of the foods. In addition, the utilization of the food, or the relation between the edible portion and the waste, and the relative cost of preparation are included. Other cost factors such as the efficiency of the workers or of the equipment, are ignored in this study. The basis for the cost comparison is the cost of the individ- ual portions of the foods. By using this basis, which includes of course only the net available yield, the question of waste is automa- tically taken care of because the market price is allocated to the edible portions only. The cost of preparation involves two elements, which are: first, the labor cost, and second, the fuel cost if the food is cooked. Since only the relative aspect of the question is desired, such costs were determined only if the cost was not a common one to all the foods being compared. In the matter of waste or inedible material, the problem is handled in the frozen food field in much the same manner as it is in -37- the canning industry. Practically all waste material is eliminated. Fruit stones, inedible fruit and vegetable skins, and tough membranes are all removed from the product before they are quick frozen. There- fore, in the case of the fresh products alone do we have any appreci— able amount of waste. The quick-frozen products are also prepared for cooking or table use. Cleaning processes, peeling, cutting, pitting, sorting, and such operations are all carefully done prior to freezing. In this respect the quick-frozen products are similar to the canned. With the fresh products there is a different problem. .All the labor cost neces- sary in preparing the products for use must be added to the market price to obtain the actual price. Although the amount of fuel required to cook a food is a factor in the actual cost of the food, this factor was not computed in this study. Not all of the fruits were cooked since they were suit- able for table use as purchased. The time required to cook the foods that were so treated is somewhat indicative of what the relative fuel cost would be. All of the fruits, except rhubarb, wlich were cooked were made into pies, and did not show any noticeable variation in the baking time. The three vegetables and the rhubarb were stewed and showed the variations in the time reguired as indicated in Table X. -58- Table X. Cooking Time Required --,.l--_--c_- c--n-___w_-_._--l.-,__--_._ we. . Name IlFrozen . Canned*. Fresh 1 Green Peas 3) 20 ”11171;...39. min. )“5 min. 2 Green Lima Beans ' 26 min. 10 min. _ ------__-__ ”...--___?n-_-,-, ‘ ... 3 0.0m 9.11.91.10.91).-- visa-21.2.1... ,19.n1i_.s:.,._._- ..-- 4 Rhubarb 7] a min.____* ..-- (L 1.01.1793; ] *This was merely heated through. As would be expected, the fresh products require the longest cooking time. Since freezing tends to have the same effect on some products as cooking does, scum of the frozen foods require less cook- ing time than the fresh. Canned foods, of course, have been sub- Jected to cooking in the preservation process. This material is by no means conclusive. It merely indicates the possibility that the fuel cost may be less for frozen foods than for fresh. The data in Table XI show the factors used in computing the cost of the products, and the final cost per individual portion. -59" Table XI. r Essential Factors Used in Computing the Costof the Iroducts and the Final Cost. .... W _ _ __7_ v __ ... ..-- _ _ ,_ _.,. ,;,_-,.._ ,_ - -..- ...- ...... ... .-...- ..- 77.. .»—. .. .- . ~— —- ... —. .1 - — — - -- ~- ~-—0 ~-<‘ » *‘ “H‘Tw '"““-‘ ‘ .....- ‘ ’ _M se.—...“... _ _- — .- _ _. ..._. _- . -’—~- n‘.~. .. - ~.,- ... ..-—.... -—~.~.HV...-... .. .... .- M .4 —- .- - a... _- . _. ‘...._..,.-.. *«a..._.._. ...H ..r...._..... ... .. ... .‘ ... ,. _ .. .. weight Leasure Size of Unit So. of Local Larket Labor Cost Total Cost of heme harket Unit.per Unit.per Unit. Row Used . or yortion Portions. Price (Rate per hr.. C at . Individual {ffigipggf per Unit 0.55 per Unit hortion “3‘2: ‘SIT‘I‘L‘: 3.2.3:; 1.2;": T: ...: 2-1:? 1 .I Z l: I: I: T???::::““'IITSSTZL: ””‘Z Z'T‘I '1’: ’ :"Z'Z_:.::;::.T‘::._ZZTLJ '“r—g: ‘: _ ‘ ’ _ 3: :‘Z'ITT‘I‘ZZ'Z T t j .‘ 'i _Z T _‘ -. I " “T 7’“) ”I“: Z": :2:2-J’:4:.:‘T I. I T " ‘ .' ‘ i 3" S3227“ ) i l apples frozen ‘ l5 5 7 th- 4 pies 1;" tins 40 .55 p.55 a .015 2 canned Io. 10 can 0 4 5 qts 5 pies 12v tifla 50 .47 .47 .015 - fresh 1 peck 5 [4 qts- (”fl pies 12” tins , 40 .85 .55 .50 .015 ...—-. —. ... - .--... _.__._.. .-....- _._ - ,_ _, ... w-_._-,..... .. ...... _.._. ..- . -..... ;. ...... - ~w- --.“ -»»-.. -... «...- — .- -m- 3 v -, -— _._._._~...._.-__H ~-——- """- ~“"'"“ “~‘Ww' ,____ 1 _ . . . - .. P‘ .--... ...... .— -. n _— -. - - A .. . .. . . . . . ...._._ -...-. .... _ 2 apricots frozen id 190 sauce 5 halves 4‘ 65 ‘ 2.72 ‘ 2.72 J .045 halves canned‘ No. 10 can” 6 J 4 '07 * sauce ' 2 halves 55 .85 .85 .025 ‘ . halV35n--m--n---l-q-e.m. _ _- , .h- -_ - . _ . .,-rn--,q--l--- Ml-.-..-------- . . l .l. 5 ‘Blackberries frozen l 15 ) 7% qts. sauce 30. 12 sc00p 75 2.52 2.52 ‘ .051 , canned ho. 10 can e 1 e 5 qts. sauce jg. 12 scoop 30 1.00 1.00 .033 4 Blueberries frozen 8 i 4 th- 3 pies l2" tins 50 1.56 1.56 .052 canned no. 10 can e g d 5 qts. 5 pies 12" tins 30 .90 .90 _05 --....._..J -..-.. _- ,W W - , , -.--.- __ _ - - .. .. , - .- I . , .... - -..... -.-“ ....- .- ... ~ .. —- —» - -- -- ~ -. —~«~»— —--—- -..- =- ‘ ~w ~-—- ~—-4- _«l...p.-_-.._-.-- ----.-n-.. .. - .. .. .. a... . - .-- -.-- .. ..."..- WWW“. ‘ '1 r7 ° . .... 5 Red Cherries frozen \ 8 l 4? th- 0 pies i 12" tins 50 1.25 l.20 .041 - - 1 r r“ 1 r' ' . canned Ho. 10 can) 0 : a Of qts. é ples 4 5O .92 .92 .05 6 Red Currants frozen i 16 8 qts. ' 80 5.52 5.52 .044 «‘- -... _ .___,.n W, _ ,,_. 4...... -___ . '._ ...... -.»w ____ .v .-.... _. ,_,_, - w... 7-..... ... ., . -. ;.. ._ .. ... >- ”...-.- m-u-—_—-—-—~»-o v ~ — - w ...... ~ «— - -"“ *'~ -..". b “_H_.._...__ rvw .-. ...-........ ...... _N‘ i , . ’1 . 7 Grapefruit frozen 83 4_qts. Sflladfi 40 1.52 1.52 .058 Canned No. 5 can 5 8 ‘13 qts. salads 15 .58 .58 .059 fresh 95's ‘12 salads ;4 sections 5 .05 .042 .072 .024 .- ' x ‘ ... o H . .. -....-“ W _ __ - p ,, WWW 1329 £31- 12.11;».-- -..... ......esrzi12n: L... - - - ---- -.- - -..... ...... - - .--- - - .. - -.. -...-. ”...... -- - ____ m - 1 .. . . . 8 Looseberries frozen 10 : qts. 9 ples l2" tins 90 1.75 1.75 .019 T \ [a '1 r j ' a . canned no. 10 can 0 o 55 qts. 5 pies l2" tins 50 .67 .67 .022 9 Loganberries frozen 8 5% qts. sauce No. 12 3300p 55 1.52 1.52 ..045 canned ho. 10 can 8 ‘5 qts. sauce No. 12 5:00p 5O .95 f .95 .052 1 .. .1 l.......,_.,,. ”W _ -- _ -.- _ _ - . ..... - V- - .1... - -- .-..-. --..-. W -..-..“ ....-J. .. ._ - _, W..- I ‘\I .2 [1:0, ..., Table 51 (Con tinned) 1 Essential Factors Used in Computing the Cost of the froducts and the Final ”ost. . . . . . .... .....- -..w.- —.-.-.._-_1 m..»~--- . .-. ‘ Jei'nt heasure Size of Unit No. of Local market Labor Cost Total Cost of frat." ' " ‘ ; —- .1 g - ‘ » _ _- .... 3 ' - ' ‘ v~~e garnet Unit)per Unit.ger Unit “V” LSBd or POIIIOL .Portions. rrice »Rate Per hf- Cost . Indiv1duai flbs.)0z. per Unit 5-35 per Unit Portion : : 3;)“: ““:‘_‘_‘ : ..-- " .....: ‘ .' __ ,_‘ _‘ j "‘j " “ ‘ ‘ __ ..f. ...- - I 1.- - - -. .. ... . .. _ - L ,__,;_;._1; —~——«- 1.-...- ----~ ~ ~ ~ ~“'"“""“—"‘""‘ “"N“‘*“'“~~ ~----~-~ ---—~---~~~--— - .- —-- -..- -..----..----.- ~4 -..»--- ...-..“ .....«_-'_ .. --- ..- .32.: -:_,- WW, _ ,_ _: T:::j:~;:: . '7 (’7 l ._ (f! P . 2 H ' " r2 311' Cir-I 3 3 ‘0- 10 Eeaohes retzen sliced 3; 0. ate. 0 P133 ; 12 tins 50 w l~v5 w loco . n ~04o - . . "-7 -. ' .:\ n ' W ’ ,-.. -" I.‘ n ‘ canned sliced No. 10 can 11 3 qts. 0 L19» , 12 tlno 50 .04 .04 f .021 O . frozen halves 85 56 sauce ; 1 half 56 1.40 1.40 , .025 canned halves L0. 10 can 6 11 55 dance 1 half as ‘ .64 ' ‘ .64 ’ .018 - ..--..“ ..L..--.—~4...~..._ ~..-.-..—.... _ . ..-. ~.. .. ‘~ V‘ _...._ ... .- -‘ _‘ ‘."‘.""-“"‘ "-"‘""’ ‘v .-,_. ...... - .-._—- ... .¢.- ..4... -..-“ .“ -..... ‘.--._..--l.- .....—_....- .. H—_ ...... ”—4 —_ .. ... .—.“~~.Q—- ua—uw ...- --...--_. .. V n l u I I i - .- ...... ~ ... . _ —~ ...—-..a— C... ...—H - - om... "...-.-- .— . ... ~. -.. . . 11 Iruno Ilums frozen . 8 ‘ 220 ’ sauce 4 halves 55 1.12 1.12 .02 1 halves canned N0. 10 can 0 10 52 sauce 2 wholes 25 .64 .54 . .024 wholes , .. t‘ .--... --....fl.-.‘ ...... -., .. .._.._..._. ' ““*"“ ‘- M...— l - -—.- 'd ' ‘ “- "'“'~4>¢ - - ———-—~.—_._.—-..- .—-.4 .- ~. a a v ... -..—.....- ._ no... .- m— .8.-.. _. --4-—- -...- _. --... ... . I U 7 qts. sauce ¥ No. 12 8000p 70 5.04 5.04 9 .045 10 d qts. 88000 NO. 12 SCOOP 50 1.40 1.40 ~046 J O L\‘ {1} HI ...) .L-J C- C. 1 lLiHaspberries -1 ) cuiried. i3 . 11) car: I 1 >- — “.--—.... ...-.... -- .- -—...<—.e»u.x.>.-.»J ._ ,. .. -_ .. ~— -. ... re 0'— ... “ H ' ‘ “n-.. . _ .. ... .D—o—QA—o p-—-o4—-v- ...—- m-a- . ~— _ ... ~ - _- -.. H I ‘ e. -.. -.4 .4 .- -— n < - "' "" " “" “W ¢‘--v~o—-O‘V~¢-~¢1... - - ‘ _-~~m>~o—o—_—o--- MI.~--.‘*I-_~ I _. " - I, ' ”"""‘~-‘--‘- —-«.-.O—<---..—.‘ .... ”nab 14 Strawberries frozen 8 4 th- sauce “0' 12 SCOOP 40 1.54 1.64 canned 30. 10 can 5 la 5 qts. sauce No. 12 scoop 30 1.45 1.46 fresh 2 5 01mg sauce NO. 12 Scoop 4 .16 .06 .041 .048 .22 .055 loan .— .. . ...-...... .N-‘n—‘ ‘ .‘ v .— .- ... ‘ ...... ...-:-—¢--~.- ;_o.— —. . ,._ ”a -. ....---...- .. - ... -. - -- ~4>-—...-~....,..,._— ... .....- - on... 7.. .h ...... .. e—wph~—.. ......— I .-...- ., . ....A‘. - ~ ' I ...-.... amp—- .... .. ... ..‘..-...--.. ... _ . .._. »- —-—-0 . ... “. I. ~ . . ¢ - 4.80 .05 ‘ m - + , . "H‘ I 15 Corn on the Ooh frozen carton 8 doz. buttered one o ear 95 4.80 D (ear lb '82 .82 .055 canned To. 10 can 0 15 ears ' buttered one V ...—-..."M—w ...e. M ___.. ! --. . .- “.-.—.... _. § —~- . b-HN . ... ”-‘n -... -- o .9- - -——-._‘...- —-\.-- *n—Jb-—-—..--- a... “in... m.-.-...- 1.. -.., - “...—....~_—- - -__,- ur..- .. “---~. ...~.. ..--.-filn.-. __ - _. - --... - — -. -.....- -..-“- 15 Peas frozen (a buttered NO' 12 SCOOP 65 2-80 frozen (b) 5 , buttered No. 12 scoop 55 canned he. 10 an e 10 5 qts. i buttere? NO- 12 scoop 52 .90 .90 .028 fresh 10 1 qt' buttered NO“ 12 SCOOP 22 1-80 .518 2.118 .096 ...—“v... -—--..-.--n—.- ...—0‘ V ,__u C O]: mp 9 rt- 7 J 0 v‘\‘ V‘- 2.80 .043 O . - » — - 1 -- at - . >— - ~ ~ ‘7 ...—u.“ ' 4“"‘0.—--.-r .. -..-m... a .— —.- -<-_...—-... 'H ...-_u L -— . - - - en‘- _. .- --. no. . . -.l- .. . —-._ ...—.-—-.-.r.—_....—.oo-v ‘- o. “HM—.._....«_..._ .--WH -'---v-o~———nh—-~¢--.— --~--- n...-....~___ - I 17 Lima Beans Frozen I 10 7 qts. buttered No. 12 scOOp 72 3.40 3040 o Canned No. 10 can 6 10 5 qts. buttered .J No. lgzscoop 57 047 Q .86 .86 0026 w..- - —... ... .a p _ _ _ .. v - .. “a. ‘. h.‘ no—- ...-.- ._.-..-. .....- am ~,. j. ‘ ' - __ I -".“""—““ “* N s -<'0 - C-M-.. . ”...—...... ...—....I . “...—u. ...... “mm- ...—... .-.-.-.... . . -..... -._.. ...._.. .. ”......” “-.-... - ~-a-~~—<<”.‘.-¢—o.---¢w.- ---“... - o - - 0-... db . . - bu. - _. . ....4- - —-—.~.—-..--—.—.~- “......_ .J -41- In Tables XII, XIII, XIV, XV, and XVI are shown the price relationships on different bases. The data in Table XII show the average costs of the three classes of foods for both fruits and vege- tables. range in the prices of the different classes of foods. Table XII. Average Cost of Each Class of‘Product. The minimum and maximum cost figures are given to show the Fruits vegetables “ Class 4 Average , Fxtremes.‘ Class . Average.rr"£§323¥3§3f“*‘ minimum hex imum minimum . haxnnum Frozen .055 .016 .052 Frozen .047 .045 .05 Canned .02§-“n;gl§_v .055 Canned .056 .026 '05§———+ green .027 ’ .014 .024 Fresga .096* ‘ *The only fresh vegetable available was green peas. The data in Tables XIII and XIV show by columnar graphs the average price levels of the foods. The products are divided into two groups depending upon the number of classes of each food that was com- pared. The proportion of the total cost that was due .0 labor is shown in the case of the fresh products but not in the others because of the relative unimportance of labor in the cost of the canned and the frozen foods. . _,____‘_ * 7' -V- I “4 ..- 4 - I 0 v —’ I “ "°‘—9'— 0—4.. _.”'+—f—o +.+_lrr_‘1 "-V 1" -.,. | - ‘ * *M_.__. V—pruo - . . + - I . 0" . . - - . . 1» . o . . - . . - .V—Ir—+. *7- .... .7.—-. 1h . . . . . - p ,_ .7 . .. H—o . ”.--..- ...I ”--.”--i. .I. -... .-Eukwl,“ >-H~ ... . . . . . > ~ . - - ~ - . vIr»‘ . . . - - . . o—«HWo .V. 4 - -rr..—. —o—o->—+—o—o—. ...»FoI y -.. 4 a . . . - . - . . - r . - - . . . . ' I... . a . IL . .7. - 4+. , . .74 .—< I }- . I._' . . . . y - . . . . - IL . . ~ Tat‘e y— H-. -.—+—« . . . , H—qE—Fo—‘1 o ....»47. If- -—« - - - . . '1 - - ~ ~ - . . - . ~ - 4ro+~+.-o—o . . . I— . . . - kw» 0—»»< - .4» .7-1 ,. ..4,.- . - . . - . . - . - . - . 4y . . . - . . . r. PM- . . . L. .'. . . -..”.«w .I -..». - 1-4.». . - ~ - I ~ . . - - - - ~ - . II— .7+_Lro—. . . L- . - . . 7.74. . . ~. . ‘o‘ - J». - . - - ’I’ 0-. ° ' . . - - - r - 0 ' ‘ ~ . ,+,_*_,__,_,,, - — I» . . .-. .v~~—<>—o 0—1}. o NJ» I . >4r~ . o » . .4 . . o . - 0 . v1» - o—+~ . . I. ._-.__._...* . ow—I - o . . . . ..L~ovr4y. .4». I I. —-H-o . — . .—- p- . - - o - ~ 0 > ' v - - > 0 over. - - - o» . 'IL' «a. . -. o " *' ~ >~ - ~ . - . I». - - . - - 0 ~ - ‘ - 0-. - r . .— P... - r - 4» - . . . Hp—o —.4 . .4 ¢ .4 >«—o4}. . . . . I. . . . . - . . . - . - - - ._.A. - ’ If . . .4». 9 - . I- l k- ‘ 4} - - . . . >- ..- . . r» . - - . - -—- - . - . . _4 ..I - . >- .4 . ' . . . ' * ' RAGE * RES I ' ‘ | ”a! .. . . . ‘, . _ _ , . . .. . - . . -' p . , _. . ”I . . w P ~ 3 a t ~I > - 4»- ‘ er. 1 lVl ma -4 ? r—--1 ' . . -4 ‘ Fa- . - I ., , - . >——oo .- - - - - . , _ , - - -4 v r.-o»4>- - - . - . . . >0 —. . ”4.. s 4 . . .. I. . - . >~ . - . . r- -I .4 . a - . . . - - e . . . » ~- --.. ICBIF. a; Grow? A. i, . Ptléfis 0?. Show? B . - -I . I , . . . . - . . - .. . o , - .. .. f. . . ..IQmuEas only) --w~-€ ‘ Fvoxfl'vx---__- go‘H‘PM ~~< .. “1 ~ - . r—o - ~ - - - < - ~F¥ou-.---r- «m .M 3~ . ~ ~ 1 . .-i- - - . I _ . , , '71 r- - - . .4, - . 5 C§\W‘L*7-'~‘- .oH .- . .-.-...-..t .. ....-’. AlgaetIA- .4319 LA .. .. .-..Inn--. _. ...-I . , ._‘.I - - , F"”+ . L ‘, ... - . . _. . .I . I .. - . ..‘anshi.---. . ; ‘ ’ ' 'I . i 0 o O ,_ i ..-... ‘... ..-. i.-. 4 T IA-' '>' I. .. I l"; . ..... ’-.-. *.-‘- ;.. L Y ¢ .-. i--- O ’-.- ..-_. C . -. Z, - y-.- l I I .1 ‘ f |. ., A v V ' 9 . -44- The data in Tables XV and III show the cost levels of the different classes of foods rated with each other. The class which had the highest cost, the second high cost, and the low cost for each fruit and vegetable which were available in the three fODES is shown in Table XV. This group of products is called Group a. Table X . Cost Levels of the Products in Group A By Classes No. ‘ Kind of Food Highest Cost Second High Cost Low Cost 1 Apples‘d‘ frozen canned .,- fresh 2 Grapefruit. ..IIEEEQEd frgaen__ fresh 3 Peas ____ fresh frozen .~_ canned 4 fihubarb ‘ frozen _' canned _ fresh 5 Staawberriaa._ a- _-..fir§.sb._-_ - ....___.<3.a1.n.ed - I frw.ea.__I The data in TableXVI is similar to that in Table xv 5385655 that only two classes of foods are compared instead of three since the fresh product was not available. This group of foods is called Group B. -45- Table XVI. Cost Levels of the Products in Group B No. 1 Kind of Food iIEiE her Cost I Lower Cost (...—...... -....- "' "'"' “ "I IJJZIIJ’ZZZLZLIZZZJ 1. Lap_ricots - _”.mfilfl_frgy§1._fi‘Lfiwpanned_ .“‘ 2 Elderberrics ‘__:-‘qanned____J.“frozgn.afl hi5... Blueberries ...i _ I “Inseam..- .1. l -....9.aa_n_6_d._._..__ 4 Fihed Cherries I_.;§EQE§QM.-IIllJ¥¥¥B¥l-- _.ji___j;qgquerr1°° ..-;.l-9§EQQQM_i,{ln_t?Q§§3a_._ 6 I Loganberries 9";§rozen._*_L._‘ngyygi-* 7 lodgliél-...-_r_; frOzen __‘;_.Jgnyn¥2__‘ 8 Prune Plums ___‘ 'r”_c.a_nn<_~3:d_ :_._: -.-.ILZQZL‘EQ- ..."..- Resp berr 123* L canned I mfr‘ozen"- _l_Q_.__l Corn _on the Con _ I‘ Canned - frozerL 11 Green Lima neans£__ frozen any§§i_- In general the correlation between the price levels seen“ s to be closer between the frozen products and the fresh products than be- tween the frozen and the canned ones. In the absence of a fresh pro- duct on the market, the price level of the frozen.product is higher than that of the canned. However, the average difference in cost under such conditions is only p.008 per individual portion. The presence of fresh products on the market changes the re- lative price levels of the classes of foods someu'hat In addition the effect differs for fruits and for vegetables. for fruits the price levels for the frozen and the fresh.products are the sane, and they hold a position below the price of the canned fruits. Green peas were the only fresh vegetable on the market during the course of our study, but the price levels of peas probably indicate the relative positions of the three classes of vegetables. The canned vegetables undoubtedly have the lowest level; the fresh vegetables reach the highest level; and the frozen vegetables find a plane sonefihere between the levels of the canned and the fresh but show a notable correlation with the fresh products. -45- D. The Growth of Bacteria in Frozen Fruits and Vegetables After They Have Themed"I The object in this part of the study was to secure general in- formation on the growth of bacteria in frozen fruits and vegetables after they had thawed. Samples of the foods used in the other experi- ments were taken immediately after the containers were opened and were exposed to conditions which would be similar to the expected institution- kitchen conditi ns. By observation over a period of time it was be- lieved that the changes would be measurable, and by the correlation of these some conclusions could be drawn. This report includes data on nine different items: six fruits- blackberries, currents, peaches, gooseberries, strawberries, and rasp- berries, and three vegetables--peas, corn, and rhubarb. All the foods were selected as representing types of foods often treated by the quick- freezing process. The indirect—brine method of freezing was used for preserving all the experimental products except the green peas, which were frozen by the cold-air-blast method. The frozen foods had been in storage a considerable time when the tests were made. Although it was necessary to allow the foods to thaw to some extent before taking the samples, when the samples were taken each fbod showed the presence of ice crystalls. The samples were stored in a Frigidaire cabinet set at a temperature of approximately 49° F., which temperature allowed com- plete thawing. Examinations were made in general at intervals of two days in the beginning, but these intervals were lengthened to a week as the test progressed. *The writer gives with sincere gratitude full credit for the work in this part of the study to Dr. E. D. Devereux of the Bacteriology Department. -47- The bacteriological examinations were made on successive tests of the same sample. Dilutions and platings were carried out in the usual manner. Bacto nutrient agar was used as the medium. The plates were incubated at 37° C- for 48 hours. Platings were made of each sam- ple until the sample showed that the develOpment of molds, yeasts, fermentation, or products of oxidation had progressed well past the stage which would be acceptable in a food used in an institution-kitchen. Since the products were all commercial it would be expected that they might vary in the number of bacteria and that the numbers might be ex- pected to fluctuate. The order of magnitude is therefore of more sig— nificance than the actual counts. Table XVII presents the results of the examinations. A brief statement of the trend of bacterial numbers for each food is also given. -48- ago non 3.3»on non-52 HHPN band-H. eaoa I. peso» ooo.¢n covenants sopnoanoe eoueeaeo g me --II..-I IIITI: III on oqmqw odes g o . - - - I III- I 3.68 owe connoauou = we .0 IIIIOII QIIII 1- u - o 9- i ssssss I IIII- ooIL .v I h g «a I - Immune 801$. I- -I I41.I-I .. as on on .I g o eaoa ..--I--;uu ..... -rlwa ooo.nm : m a as..- -.-.IeathI I I I .. N. co ooo.mm g e 0H . h = , oom.m oom.m - = e ...... Apsouw uptoew, .. II'IIII1!|-sIv2 apes apes . . Immnosoo bonuses, on on cos a 000 a II. c m one ooo.oom oooww ow cad om om oea one uses 0 h case nuapanm n meow . nnoo Amofinhonnmam.moannonkwnpmimoannonomooo monooom : mvnannso.gmofinuopxowami owunovm meg-Ea. no»: noanmpomokp use 3.25m nonognxofisd 5 3.33am Ho 5.6.5 l. Blackberries The bacteria count was fairly low at the beginning of the examinations but showed a marked increase throughout the experiment. 2. Currants The currents showed an increase up through the fourth day, then a decrease occurred. A fluctuation also was noted. 3. Peaches The growth of the bacteria population in the peaches showed much fluctuation. First a decrease then a decided increase is indi— cated. Evidence of oxidation appeared early in the experiment. 4. Gooseberries The bacteria count in the gooseberries was low throughout, and a slight fluctuation is indicated. Probably gooseberries do not furnish a satisfactory medium for bacterial growth. 5. Strawberries The numbers of bacteria in strawberries were quite low in the beginning. However, the count jumped considerably in a week and stayed quite constant. 6. Raspberries The number of bacteria in the raspberries was very low, and it took a longer time to increase than in the strawberries. This in- dicates resistance to bacteria growth. 7. Corn. The co:n showed a high count from the start which increased very rapidly. a mold growth caused the sample to be discarded early. -50- 8. Green Fees The bacteria count in peas was very high in the beginning. The sample had to be discarded on the fourth day. 9. Rhubarb The count on the rhubarb was low in the beginning and decreased with are. A fluctuation in the count was noticed. Probably rhubarb is another poor medium for bacteria deveIOpment. In general, the results show that the bacteria population develops slowly in fruits after they are thawed. In the vegetables the opposite seans to be true. The bacterial growth, as well as other causes of spoilage, develop very rapidly in vegetables. In the fruits other causes of spoilage seen to be more important in the de- terioration process than do the bacteria. Fluctuations in counts were comnon to both classes of foods. From the limited number of experiments it is impossible to draw conclusions. These results, however, indicate that the foods can be used for a limited time after thawing with an adeeuately low microorganism content. Furthermore, the chemical and physical changes in the foods, such as limited changes in color, flavor, or drip*, probably can not be explained except to a snall extent by the growth of bacteria. *Drip is a term used to indicate the tissue juices which leak from the plant cells after the products have been frozen and thawed. -51.. E. Availability in Central hichigan. The question of the availability of the quick-frozen fruits and vegetables in central hichigan was studied by making a survey of the agencies distributing the products. There were no published data on the subject so the information had to be obtained directly fran the distributing agencies. No doubt the major organizations supplying frozen fruits and vegetables to institutions in centnal hichigan are included. The distribution of the frozen fruits and vegetables to the institution consumers is done either by the producers of the frozen products themselves or by wholesale jobbers. Since Michigan is far from the two leading centers of production, consisting of the Pacific Herthwest (26) and the tri-state district of Delaware, haryland, and Virginia, there are relatively few producers in the state. However, in the production of frozen red sour cherries, Michigan, Wisconsin, and New York lead the other states by a considerable margin. The Fruit Growers Union of Traverse City are responsible for part of the frozen cherry pack in Michigan. There is a tendency for large users of fruits and vegetables to freeze the fresh products for future use. For instance, the Home Dairy Company, which has establishmen s in several of the larger Michigan cities, is now freezing rhubarb for its own use and is planning to freeze berries during the next season. Most important in the distributing field for the institution trade are the nationally known wholesale grocers. The names of im— portant distributors who sell in this locality and the itans they carry are listed below. John Sexton and Company, hicago, Illinois, distribute frozen apples, apricots, blackberries, blueberries, red sour cherries, red currents, grapefruit, gooseberries, loganberries, peaches both sliced and halves, Italian prune plums, raspberries, rhubarb, strawberries, corn on and off the cob, peas, and green lima beans. Durand—hoNeil-Horner Company, Chicago, Illinois, distribute frozen apples, blueberries, blackberries, cherries, grapefruit, sliced peaches, pitted Oregon prunes, red raspberries, strawberries, peas, and spinach. Libby, KcNeill and Libby, Chicago, Illinois, distribute red cherries, loganberries, peaches, plums, raspberries, and strawberries. There are a few distributors of frozen fruits who furnish them primarily to ice-cream manufacturers. Among these are the Stirling- Wilsonehamblin Company, Detroit, Michigan, who distribute frozen straw- berries and frozen raspberr es, -nd the H. C. Shrank Company, hilwaukee, Wisconsin, who distribute frozen strawberries. In general, it is evident that a substantial number of quick- frozeu fruits are available in central Richigan at present. As for the vegetables, quick-frozen peas, green lima beans, spinach, and corn are easily obtained. It is reasonable to expect a longer list of frozen fruits and vegetables on the market in the future since the advent of new itens is largely a matter of improving the freezing technique. The snall number of vegetables on the market at present points to the caution being exercised by the industry in not distributing vegetables until all doubt is removed as to the danger of the poisonous clostri- diam botulinus toxin developing during storage. III. Conclusion and Summary. The novelty of quick-frozen fruits and vegetables may serve to introduce them into an institution, but much more is required of -any food before it can become eligible for frequent use. Good quality and reasonable cost are features which the consumer has a right to demand. These criteria have been kept in the foreground during his study. The conclusions resulting from the study are as follows: 1. Quick~frozen fruits and vegetables can be used successfully in an institution food departnent. 2. r"he frozen foods showed much variation individually as to quality, cost, and resistance to bacterial growth. 5. As a whole, th frozen fruits and vegetables compared favor- ably with the fresh products in uality and excelled the canned pro- ducts. 4. The frozen products showed a striking resemblance to the fresh in color and general appearance. 5. The frozen products had flavors somewhat different from the natural flavors of the foods, but this change was for the nest part slight. d. r“he flavor of the frozen fruits was best when the product was in the frozen state. 7. hhen the fresh products were available, the average cost of the frozen commodities was either the sane or below the average cost of the fresh. It was the sane as the average cost of the fresh for fruits and below the average cost of his fresh for vegetables. With corresponding products the average cost of the canned fruits was above the cost of the frozen, while the average cost of the canned vegetables was below the average cost of the frozen. 8. In the event that there was no fresh product on the market, the average cost of the frozen food was higher than the average cost of the canned food. 9. The multiplication of bacteria in the frozen fruits after they were thawed was slow, even when stored a comparatively long time. The development of mold,_oxidation, and other indications of deterior— ation was more rapid and caused the food to be discarded before the - bacterial growth was large enough to be dangerous. In the case of vegetables the growth of bacteria after the products were thawed was rapid as well as the development of other spoilage factors. iowever, the vidence shows that frozen fruits and vegetables can be used safe- ly if they are utilized promptly upon thawing. 10. a good variety of quick-frozen fruits is available in central hichigan. The number of frozen vegetables available is small but since packers are improving their technique, it may be expected that more of tLese products will be found on the narket in the future. 10. ll. 12. (~11 IV. Bibliography Baker, Go To Refrigeration in connection with Frozen berries. Food Ind. Vol. 2 No. 4 pp. 180-131. 1950. Beruy, Jo no How Freezing Effects Licrob ial Gro. th Food Industries Vol. 4- No. 0. p. 250 1952. Birdseye, Clarence Preparing, Packing. and shipping euick-Frozen Fruits an Jegetaoles. Proceeu dings LeW York Research Council Dec. '51- 1951- —-‘---c. - ..---¢-_. Where guick—Erozen Vegetables Stand iodqy. 3005 Ind. VOl- 3:100. 50 P- 215- 1951- Bracewell, n. F., We t, C ,Zilve, S. S. Antiscorbutic lotency of apples. Biochem- J. 25:155o1951. Bradley, Alice How about These Frozen loocis? Wonen's— Iome Companion 57:125. Oct. '50. 1930, Lritish Food Industrial Board Reports of the Director Department Sci. Ind. Res. Gt. Britain. 1929-50. wuoted by Eellers (20). Conduit, I. J. Cal. egr. Erp. eta. Annual Report. muoted by Woodroof (44). 1919. Cruess, W. V-, Overhelser, E. L., and Bjarnasen, S. A. Storage of Perishable firuits and Ireezing ienreratures. Cdlifo Agro Expo Sta. 131.110 1900 3240 192C- Culpepper, C. W. et al Preservation of Peaches for Use in the manufacture of ice Cream U- 3- D. A- Tech. Bul. Lo. 84. 1928. Delf, E- LI. Influence of storage on Anti—Scurvy value of Fruits and Vege- tables. Biochem. J. 19:141—152. 1935. Diehl, H. C., Magness, J. R., Gross, C. R-, and Eonney, V. b- Th Frozen rack hethod of Preserving Berries in the Pacific Northwest. U 5. D. A- Tech. Bel. 148. 1950. 13- Diehl, H0 Co 14. The Freezing of Fruits and Vegetables Requires more Research. Food Industries Vol. ZzNo. 4. p. 164. 1950. a. But You Will Like Our Frozen Fruits. b. Frozen Pack Fruits. c. Frozen Puck Vegetables. Radio Messages, Frozen Pack Lab. Bur. of Plant Ind. U. a. D. A. Seattle, Wash. 1951. 150 Eddy, W. H. 16. 17. 19. Frozen Perishables. Good Housekeepingjnaeazine XCIV:N0. 2. p. 100. Feb. 1952. Editorial Development of the Frozen Food Indistry. Ice and Refrigeration. 78:545—47. 1950. Frosted Foods Invade New York. Sales kanagement 29:22. Jan. 2, 1952. Frozen Foods Find Favor in Hotels and Restaurants. Hotel honthly nhgazine V01. 59:50. Feb. 1951. Frozen Foods Industry. Hotel Nonthly- Vol. 40:No. 6. p. 21. 1952. 20. Fellers, Co R- Public Health Aspects of Frozen Foods. AL- J. Publ Health. Vol. 22zNo. 6. p. 601-611. June 1952- 21. Fulton, S. H. The Cold Storage of Small Fruit. U. S. D. A. Agr. Bur. Plant Ind. Bul. No. 108. 1907. 22. Ireland, R. Cold Pack Barreled Fruit in 1950. FOOd Indo V010 50 NO. 522140 15.81,? 19310 25. Isham, P. L-, Fellers, G. B- Vitamin C in Cranberries. Paper read at Am. Chem. Soc. heating Buffalo, F. Y. Sept. 1, 1951 (unpublished). quoted by Fellers (20). 24.3ames,1" H. Does Freezing Kill Clostridium Botulinun Spores? An. J. Pub. Health 22:525, 1952. 25. Joslyn, M. A. Why Freeze in Fruit Sirup? FOOd Ind- VOl- 2. NO- 8- p. 350—2. 1930. Preservation of Fruits and Vegetables by Freezing Storage. Calif. fiaro Exp. Sta. Ciro N00 3200 1950- 27. Joslyn, n. A-, Cruess, W. V. Frozen Foods in raper Bottles. Literary Digest 101221. hay 25, 192?. 28. Kidd, F., West, C. Storage Investigations with Fruits and Vegetables. Dept. Sci. and Ind. Res. Food Investigations Gt. Britain. 1925-26. Wuoted by Woodroof (44). 29. Low Temperature bxpt. Sta., Cambridge, Lngland. Summary: Storage and Canning of fees and otrawberries. Ice and Refrigeration aug. 1951. pp. 260-75. auoted by Fellers. 50. hagoon, C. A- Keeping eualities of Frozen Foods and lheir Relation to Dis- tribution Problem. Proceedings New York Research Council. p. 26-32. Dec. 1951. 51. Meat Preservation Committee Recent DevelOpment of quick-Freezing of heat and Fruits. J. Council Sci. Ind. Research Australia. 1950. p. 185. auoted by Fellers (20). " 52. Michigan Agr. Exp. Sta. Ann. Rept. Preservation of Fruits and Vegetables by Freezing. Division of Hort. 191?. 55. Prescott, S. C. et a1 Numbers of Bacteria in Frozen Food Stored at Several Tempera— tures. Am. J. Pub. Health Vol. 2:225-7. p. 262. 1952. 54. Sweetman, Karion D. The Scientific Study of Ialatability. J. H. Ec. 25:161. 1951. 55. Taylor, Hayden F. What Happens During Freezing? Food Industries 5:505. No. 5. 1951. Solving the Problens of guick Freezing. Food Industries Vol. 5. 1951. MoGraw Hill, Inc., N. Y- 58. 40. 41. 42. 44. Taylor, Donald E. Pacific Northwest Fruit Growers Put Refrigerated Food News. Vol. 2, No. 1951 (Detroit) Surplus Crols in Cold Pack. 5. Serial No. 28. Nov. 1, Tucker, 5. R. Freezing and Distributing Georgia IeacLes. Proceedings New York Food Research Council, p. 6—8. Dec. 1951. Ullsperger, H. W. An appraisal of the Frozen Fruit karket especially Relative to Cherries. Proceedings New York Research Council, Dec. 1951. p. 5-3. U. S. D. A. Bur. of Chem. a Soils- Cold Storage Does not Destroy Important Vita-tins in Foods. Siebel technical Review 5(1):9, 1950. Quoted by Joslyn (an). Wiegand, s. H. New Gold Pack Berry Process. Ice and Refrigeration, Aug. 1951. p. 82. WOOdI‘OOf, Jo Go Preserving Fruits by Freezing -- I Peaches. Ga. ASP. 11:1?- Ste. 3111' NO. 103- 19500 Preserving Fruits by Freezing -- II Figs G80 1X53}. Rip. Sta. Bulo NO. 154:- 19300 Preservation Freezing. Sane Effects on euality of Fruits and Vegetables. G110 RCP- Sta. Bill. 1:00 1'58. 193].- I . n ' . '0 .' ‘ \- ‘ _A "I I H '" “ o o . , f- ~u -' .. n —" I ~' \ A . r v .m-z... , ‘ -.' .“ ". . p - ‘ l I- l ' ‘. .hx. . "2" f ’ -" ‘ V _ .4 I ‘ V '3' v. ’J‘ a ‘ x '-. v ,.,. v' J I“ V Y . '- ‘ ,c, " v'! ' . ”#1 ”V.- “ , .I‘ ‘. r} 492.4)! ." ~ r-‘u- . .‘ 712‘ - ‘} ‘»_ .3) I"; 1‘ ' . ' ‘v - . i .' . 1 x1". &‘ '3‘?“ “l I . J. . 'u . fig} ngzé’“'z.r\" 3 ‘ ‘e'fiffiifii ’19. is .~ _ "’\,1' . z- - I ‘ I - *wfim _ “we“ miTiifliliL i1? iii/[iiiiiiigi BR (ml/iii“ 5