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LUCTUATING temperatures due to many different condi-F tions may be encountered in the storage of frozen foods. Temporary breakdown of facilities or equipment, improper response of temperature controlling devices, excessive loads during freezing, lack of a separate compartment for freezing, and frequent opening of the cabinet (particularly a side-opening box) all may lead to a temporary rise in the temperature of the stored food.Statements in the literature (1, 3, 10) stress the point that temperature fluctuations should be minimized, either because excessive desiccation may result or because fluctuations may lead to excessive growth of ice crystals in the food. None of these statements is accompanied by data to prove that undue desiccation or crystal growth necessarily is encountered in such cases, or to prove that the food quality is appreciably impaired.Work a t Purdue ( 9 ) indicated that temperature fluctuation over the range -5" t o -15" F. was not deleterious to frozen pork. Workers at Minnesota (4) stated that for frozen fruits and vegetables, constant storage temperature is not important if the storage temperature is 5" F. or less. In their study, the temperature fluctuated from 0 " $0 -20" F. with no impairment in food quality in a 6-month period. DuBois and Colvin (8) studied ascorbic acid in frozen peaches subjected to smell temperature fluctuation three or four times daily, and reported that, as a result of fluctuating temperatures between 5" and -5" F., 50% of the originally added ascorbic acid was lost in 1 year, whereas like packs stored at a relatively constant temperature of 0" F. lost but 32% of the vitamin C during stomge. Their data, however, dispute the significance of this statement.If undesirable effects from varying temperatures are to be expected, they will be found in the freezing range above 0" F., the usually recommended storage temperature. Furthermore, this is the range most likely to be encountered in freezer cabinets or lockers subject t o temperature fluctuation. No data are at hand, to evaluate the effects on frozen food of temperature variations in the range of 0 " to 20 ' F. PROCEDURES STORAUE TEMPERATURES. Three conditions of storage were maintained. A standard temperature of 0 " * 2 " F. and a control of 10 " * 2 " F. were maintained as representing constant temperature conditions. A third freezer, equipped with two thermostatic control switches, was carried through a temperature cycle between 0" and 20' F. For 36 hours out of every &day period, the control was set at 20" F.; for the remainder of the period (108 hours), the other control, a t 0" F., was in operation. This cycle was such that the food temperature rose from 0 " to 20 " F. and remained there for several hours before again being lowered to 0 " F. The 6-day cycle was' automatically repeated during the entire course of the 1-year storage period. The cycle represents a magnitude and frequency of fluctuations that may be encountered during frozen food storage without actual exposure t o thawing. on Quality of Frozen ...

The purpose of this study was to determine the retention of ascorbic acid, thiamin, riboflavin, and niacin in cabbage during commercial dehydration of two varieties and during quantity preparation of the dehydrated cabbage (1) cooked by three methods ; (2) prepared as coldslaw ; (3) held after cooking; and (4) held as coldslaw a t room temperature. The cabbage was also scored f o r palatability. EXPERIMENTAL PROCEDUREBoth varieties of cabbage were from lots commercially dehydrated by the Dry-Pack Corporation a t Lyons, New k'ork. The cabbage was grown on upland soil within a 75-mile radius of the dehydration plant.The first lot was of a domestic variety; the heads were firm, averaged from five to seven pounds in weight, and had a pale green color. The second lot was of the Danish Ballhead variety ; the heads were more loosely packed, had coarser leaves, and a white color.Both varieties were stored in outside bins a t 17.8 to 18.9"C.(64 to 66'F.) until they were used, within 12 hours. The cabbage was trimmed, cored, and machine-cut into %-inch shreds. The domestic cabbage was steamblanched for five minutes at 82.2"C.(18OoF.) and the Danish Ballhead cabbage was blanched for three minutes at 10O0C.(212'F.). The cabbage was spread on stainless-steel trays and dehydrated for about five and onehalf hours in a cabinet drier.Both the domestic cabbage, which was packed in tightly covered, onegallon tin containers, and the Danish Ballhead cabbage, which was packed in soldered, five-gallon, tin containers in an atmosphere of carbon dioxide, were stored a t 0°C.(32"F.) until analyzed and cooked. All of the studies were completed within six weeks except Study 5 which was made 17 months later.Cooking Methods: I n each study except the fifth, the dehydrated cabbage was cooked in amounts to serve 50 (about two-thirds cup of cooked cabbage per person). Cooking lots of 790 grams were used. I n the fifth study the cabbage was cooked in amounts to serve 50, 100, and 200 men.Htudy 1-Boiled cabbage : Dehydrated cabbage of a domestic variety was cooked according to the manufacturer's directions. The cabbage was

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No reports were found in the literature on the retention of vitamins in large-scale food service of dehydrated carrots. The purpose of this study was to determine the losses of carotene, thiamin, riboflavin, and niacin from commercially dehydrated carrots during quantity cooking by the following methods in amounts to serve 50: (1) simmering on top of the stove, in enough boiling water to cover, for 30 minutes (directions on the can label) ; (2) in an institution-type steamer for 15 minutes;(3) boiling for 25 minutes on top of the stove, in enough boiling water to cover, in a U. S. Army field range; (4) simmering on top of the stove for 20 minutes, after refreshing for 20 minutes and after heating for 45 minutes to bring to a boil (directions in Swift's Army Cook Book) ; (5) same as (4) except using carrot bricks and refreshing for 90 minutes before cooking. Because it is often necessary in Army mess halls to keep cooked vegetables a t serving temperature for varying periods of time, the carrots cooked by directions in the Swift's Army Cook Book were held for one and one-half and for three hours, after which vitamin losses were determined. 13ISTORY OF VEQETABLEThe carrots, dehydrated by the Beechnut Packing Company, were of the Chantenay variety. They &ere cut in one-fourth-inch cubes, and were steam-blanched previous to dehydration. Raw carrots of the same variety, which had been dehydrated in the same plant two days previous to the dehydration of those used in this study, were analyzed for carotene and ascorbic acid.= The raw carrots contained 95 mg. of carotene per 100 gm. on the dry-weight basis. There was no change in value during dehydration procedures. The following changes occurred in the ascorbic acid content of the carrots during dehydration. 7.5 1 68 1 5.7 I 50 I 3.8 1 28 1 21 1 22 1