Frozen food research begins at WRRC

After the 1947 debacle in the frozen food industry, it quickly became obvious to the industry that some of the problems, such as poor color and flavor, inedible pre-cooked dinners, and even mold growth, could benefit from a more careful scientific analysis.

For some time, research in frozen foods had been conducted by a number of groups, including the USDA. The USDA had established a track record of research in frozen foods dating back to World War I with Mary Pennington’s work on refrigeration and the shipping of perishable commodities. Now, the frozen food industry, led by Helmut C. Diehl, who was director of the Refrigeration Research Foundation, approached the USDA with recommendations that it undertake a thorough investigation of the entire matter. Diehl, who had conducted research on frozen foods in the 1920s and 1930s for the USDA, had spent time at the WRRC after it opened. He pledged the full financial support of the industry to this endeavor.

Diehl was asking for a comprehensive scientific and technological study of all the practices of the frozen food industry, but there was also considerable interest in the "maintenance of the high quality of commercially packed frozen foods under the conditions of temperature and time that they would experience in nationwide distribution." The project was assigned to Albany, and WRRC Director Michael J. Copley "seized the opportunity to show-case the Center’s ability to perform such a large and complex undertaking as an instrument of discovery and invention." A large staff of chemists, food technologists, and engineers was assembled, and specialized cold-storage rooms were designed and constructed. Capable of storage temperatures from –30 °F to +40 °F, these rooms could carefully duplicate the fluctuating temperatures that were the key focus of the investigation, while novel refrigeration systems moved cold air over the test foods, year after year, through many different cycles.

In close consultation with the frozen food industry, the WRRC staff worked from 1948 to 1965 to study frozen fruits, juices, vegetables, poultry, beef, precooked foods, and bakery products. Most of the frozen food products were supplied by the industry over a multi-year period, although a pilot plant built at WRRC was used to study directly what happens during the freezing process. The first of 24 technical papers describing the WRRC experimental design and results appeared in the January 1957 issue of Food Technology with the title "The Time-Temperature Tolerance of Frozen Foods." (4)

There was considerable staff discussion before agreement was reached on this title. The ideal scenario for the industry would be one in which the newly frozen food would forever be held in a constant low-temperature environment, generally considered to be 0 °F (or lower) at the time. Much of the problem, however, lay in what happened to the frozen foods between the time they left the plant and the time they were purchased by the consumer.

For practical purposes, the question was to determine what variance in the ideal temperature a product could withstand without affecting its quality. That is, "what is the tolerance of a frozen food to adverse conditions, measured in terms of time and temperature combinations?" (5) In typical scientific fashion, this title was shortened simply to the T-TT studies.

As assistant WRRC director Wallace Van Arsdel explained, the major objective of the T-TT work was to study the changes in frozen foods as they proceeded through the distribution system, determine the deviations in the system that would still allow a satisfactory consumer product, and make recommendations for improving the distribution system itself. Once these results were available, the WRRC intended to improve the selection, processing, and packaging of frozen foods so that they would better withstand adverse conditions in the distribution system. A second goal was to find suitable tests that could be applied to a frozen product anywhere in the distribution system to see what changes may have occurred and whether the products were still commercially acceptable when they reached the retail market. It was the beginning of a massive and arduous effort of many people over a long period of time as they attacked a complex problem using basic science and engineering.

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Early methods of food preservation | A chance discovery | Frozen food chemistry | U.S. Agriculture turns to science | Frozen food research begins at WRRC | Defining "Quality"Chemical reactions at low temperaturesChlorophyll as a benchmark | Major scientific results from the T-TT programSocietal impact of the T-TT program | Landmark designation | Further reading and acknowledgments

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