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ABSTRACTS
Taking the results of these experiments into account, the Minister of Agriculture
in consultation with the Agricultural Research Council, decided to carry on propaganda
for the extensive use of treated straw commonly known as the straw pulp. [N. K.]
Quality of frozen poultry as affected by storage and other conditions. HAROLD
M. HARSHAW, WALTER S. HALE, T. L. SWENSON, LUCY M. ALEXANDER
and R. R. SLOCUM. (1941). Tech. Bull. No. 768, U. S. Dept.
Agri. Washington, D. C.
F ATTENED and dressed cockerels representing light and heavy birds of the two
breeds, Barred Plymouth Rock and Buff Orpington, were used in this investigation.
These birds were packed in wooden boxes, frozen at —5° to —6°F. and stored some at
0° and some at —20°F., under normal refrigerator conditions. All the birds stored at
0°F. were undrawn while half of those stored at —20°F. were drawn. After one, two
and three years of storage, the representative carcasses, together with fresh chilled and
fresh-frozen ones were examined to determine the effect of the preservation on their
quality.
The loss in weight during storage was much higher at 0° than at —20°F. The
drawn birds suffered greater loss in weight than the undrawn ones, stored at the same
temperature, though the differences were sometimes slight. The loss in weight was
approximately the same after two years of storage as after one year, but was higher
after three years.
The external appearance of the dressed birds, as indicated by colour, bloom, condi-
tion of skin, and degree of freezer burn, was adversely affected by increased length of
storage. This effect was more marked at the higher storage temperature of 0°F.
The amount of glucose in muscle tissue and the acidity of the intraperitoneal fat
tended to increase with the period of storage. The results of the other chemical de-
terminations—including moisture in breast muscle and skin, acidity, glutathione, amino¬
nitrogen, proteinase activity of the aqueous extract of muscles, and proteinease activity
of the glycerin extract of muscle—were not affected by the conditions of the experiment.
Considerable numbers of bacteria remained viable, in the muscle tissue, even after
three years of storage. Anaerobic organisms were present in a smaller percentage of the
stored birds than in the fresh ones. However, there was no indication that the bacterial
counts were affected by any of the conditions of this study.
Light birds required relatively more time for cooking and lost relatively less weight
in cooking than the heavy ones.
The palatability of the birds stored at —20°F. was rated better than that of those
stored at 0°F. The difference was greater after two and three years of storage than after
one year. The higher rating was due to a greater desirability of flavour and aroma.
There were also more favourable and fewer unfavourable comments by the judges on the
flavour of the meat of the birds stored at the lower temperature than at the higher one.
The intensity of flavour was higher in thigh meat of birds stored at the higher temper-
ature. The desirability of flavour and aroma was rated better in the breast meat of the
undrawn birds, but after two and three years of storage the thigh meat rated lower
in these respects. The desirability of aroma was slightly better in the drawn birds after
one year of storage and significantly better after two and three years than in the
undrawn ones. The intensity of aroma increased and desirability of flavour decreased
with length of storage. Tenderness also decreased with the increased storage.
It is concluded that temperatures in the neighbourhood of—20°F. are more favourable
to the maintenance of quality in dressed poultry as shown by external appearance and
palatability. Drawing, apparently has little effect, either favourable or unfavourable,
during customary periods of storage, but during more prolonged periods, palatability of
the thigh meat of poultry is affected adversely if the birds are not drawn. [T. S. K.]