Home Freezers and Freezing Equipment

Operating characteristics of seven makes of home freezers were studied. More work needs to be done to establish the relationship between the results of engineering tests and the performance-in-use values that indicate a satisfactory piece of equipment. On the basis of the work done to date, however, it appears that in available chest-type cabinets, under normal operating conditions, temperatures in the upper fifth or tenth of the compartments are higher than that recommended for satisfactory storage of frozen food. A separate freezing compartment is desirable to reduce temperature variation in the stored frozen food while a new load is being frozen. Freezing compartments, however, should not be as large as those in many available freezers.

To find out how well home freezers could maintain low temperatures in the frozen food when the cooling system is not working (as when a storm cuts off electric current), five representative freezers were studied. With the current off, the time it took packages to reach the melting point of ice (32 F.) varied with the freezer and with the amount and position of frozen food in the cabinet. In one freezer, with the storage compartment filled, it was 44 hours before the first package reached 32 F. In another, similarly packed, it took 80 hours. The freezer that took 44 hours to reach 32 F., when full, took 33 hours when only one-fourth full. There is need for better insulation at certain points in the freezers in order to slow down the passage of heat from outside into the food compartment.

It is better to use dry ice (solid carbon dioxide) when the freezer is not working than to depend on blankets or other outside insulation to keep down the temperature of the frozen food. Freezing rates have been recorded under varied conditions. In a freezing compartment with a fan, the average time required for food to reach 0 F. was found to be 7 to 8 hours for small loads (6 to 12 pounds of food) and 15 to 20 hours for large loads (30 to 40 pounds of food). With a load of about 20 pounds of snap beans in pint cartons in a freezer without a fan, 24 hours elapsed before all the food reached 0 F. Double that load (about 40 pounds), in a freezer with a fan, reached 0 F. in only 15 hours. Little difference was found in the time needed to reach 0 F. in foods packaged in different kinds of cartons. A comparison of food in cartons with food frozen on open trays showed that green snap beans and asparagus in closed, sealed cartons needed 7 hours to reach 0 F. whereas those frozen on open trays required only 1 hour.

These figures help to set up instructions for homemakers as to when food may be ready to move from the freezing to the storage compartment. They cannot be used to indicate whether the rate of freezing affects palatability and nutritive value in the final product. No clearly defined results on this aspect of freezing rates are available at present.

Investigations were also started to determine the temperature limits allowable for long-term and short-term frozen storage. If higher temperatures and wide temperature fluctuations could be used, the cost of manufacturing and operating home freezers would be less. In cooperative work with Cornell University, it was found that with temperatures fluctuating between 0 F. and 20 F. foods tend to dry out unless properly packaged. It was also found that more ascorbic acid is lost as the temperature is raised. Thiamine in pork is not significantly affected by the temperature conditions or period of storage in the freezer. Rancidity, however, was greatly hastened when the pork was exposed to temperature above 0 F. The palatability of all products except meat was lower at 10 F. storage or following 0 F. to 20 F. fluctuations than at 0 F. All palatibility factors for pork were affected by length of storage but some were not affected by temperature.

If the temperature usually prevailing in the freezing compartment of a home refrigerator proves to be low enough for brief storage, frozen foods can be brought from community lockers or purchased and kept on hand for a few weeks by people who do not own home freezers. Studies are under way in cooperation with Iowa State College which will help to answer the question of allowable temperatures for short-term frozen storage. Results now available indicate considerable differences in frozen foods with respect to changes in palatability and vitamin C value. The temperatures used were 0, 5, 10, and 20 F.; the storage times were 2, 4, 6, and 8 weeks.

The concentration of the vitamins, thiamine and niacin, did not change in any of the foods studied-peaches, rhubarb, pineapple, soybeans, corn, peas, and snap beans.

Studies have recently been completed on frozen peas. Although thawed in different ways, the ascorbic acid value before cooking varied very little, from 54.5 to 51.6 milligrams per 100 grams. Frozen peas cooked in a small amount of water without previous thawing retained 85 percent of their uncooked value. A downward trend from this value was apparent for peas cooked as above but thawed 3 hours at room temperature, 9 hours in the refrigerator, or 33 hours in the refrigerator. The retentions were 81 percent, 76 percent, and 72 percent respectively. No differences in palatability were observed. From results on this one vegetable, it appears that, when possible, frozen vegetables should be cooked without preliminary thawing. On the other hand, if some unexpected event forces the holding of a thawed vegetable for an extra 24 hours in the refrigerator this will probably not affect palatability. It will result in some loss of vitamin C.

THE AUTHOR Esther L. Batchelder is head of the Food and Nutrition Division of the Bureau of Human Nutrition and Home Economics. Besides general responsibility for the work of her Division, she has taken an active part in home dehydration and freezing research. Before joining the Bureau in 1942, Dr. Batchelder was director of Home Economics at Rhode Island State College. She has taught and done research in nutrition at the University of Arizona, the State College of Washington, and Columbia University.

Clothing That Works

by CLARICE L. SCOTT AMERICAN women, like men, want and deserve their own work clothes. They are tired of having to wear the family's discards, or men's too big overalls for outdoor jobs. They are tired of fussy little house dresses made for looks alone. Instead, they want clothes planned and made for the different kinds of work they do-functional work clothes that are comfortable, safe, and practical, but handsome, too.

Women's need for work clothes long ago attracted the interest of the Bureau of Human Nutrition and Home Economics. Farm women often wrote to tell us their grievances. Some even took the pains to sketch styles of garments they had worked out themselves in an effort to get something satisfactory.

Our clothing unit investigated, and found that no manufacturers of ready-to-wear clothes had ever produced lines of women's work clothes. Farm women could not go to local stores and find special departments where they could buy their work clothes. Nor had manufacturers of patterns offered helps for women who could make their own. We found also that, the clothing industry was just beginning to offer the time and incentive that designers need for studying and developing clothes for specific purposes. On the other hand, the buying public was reluctant to pay the additional money cost of good design, and did not appreciate the full worth of scientifically designed clothes, yet unwittingly was paying high for clothes-if not in initial costs, then in discomfort, fatigue, accidents, inconvenience, waste of time, and premature wearing out.

From that research we found that comfort and freedom of body activity are essential to working efficiency. If you can work in absolute comfort, forgetting all about the clothes you have on, you can concentrate on the job. But if attention and energy are divided because you are too warm, or too cold, or something about your clothes chafes or gets in the way, you waste both time and energy.

Actual wear can prove best when design, cut, fit, material and workmanship function together, making a garment responsive to body movements and the tempo of the job. We learned that some features of a design give and go back into place when activity is slow or normal, but for another kind of work that requires speed or extreme movement these features are not always adequate. We also found that closed protective garments, such as women wear for winter outdoor work, need more action features within them than do hot-weather outfits, which are comparatively open and cover only the body proper. The effect of climate and the temperature of workrooms must also be considered. For instance, if work causes one to perspire, fabrics cling, and free action is hindered unless design features are devised to prevent this restriction.

Since materials, like designs, affect body movement, their functional qualities need to be considered together. A hard, tightly woven, inelastic cloth contributes little or nothing to free movement, in contrast to one that is soft, elastic, and more loosely woven. Yet those hard fabrics are often desirable for their protection and durability. Then, design alone must provide free action.

A protect-all designed for farm women who prefer skirted work outfits illustrates this. The material, a closely woven shower- and wind-resistant cotton, was chosen for protection against cold and wet weather. It also resists soiling, a practical feature. To assure free action despite the lack of give in the cloth, the garment is loosely styled. It has reaching insets under arms and action pleats in back close to the sleeves. There, pleats and sleeves can function together to provide instantaneously ample shoulder and arm freedom. For further free action, the sleeves have shaped elbow room and surplice cuffs that fit automatically. The worker is not hampered by too full sleeves or buttoned cuffs that will not give.