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 Penningtons
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 Centers 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