The effect of fluctuating temperature on the quality of eggplant fruit and spinach during the low temperature storage was investigated under the various ranges and cycles of fluctuations in which the average temperature was not changed.
Fluctuating temperature affected the freshness of eggplant fruit more severely with increment of the frequency of fluctuations. Subsequently, the periods of retaining salability were shortened with the degree of fluctuations. It is valid to show that eggplant fruit is kept under the average temperature of 10°C when the temperature fluctuation is within ±2°C, but when it is over ±5°C, we cannot expect the effect of low temperature storage. As the cycle of fluctuations becomes shorter, it is likely that the tolerance of temperature fluctuation becomes smaller.
In case of spinach at the average temperature of 3.5°C, the bad effect of fluctuating temperature is produced more on the changes in reducing ascorbic acid contents than on that of freshness score, and the degree of responses to fluctuating temperature differed among them. When the fluctuating cycle was short, the effect of low temperature storage was observed on the temperature fluctuation of ±3°C ; therefore, it is permissible to show that the average temperature throughout the storage is 3.5°C.

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Prepared frozen foods on the market such as hamburg cutlets, chiken balls, croquettes, gyoza (dumplins stuffed with minced pork), cheese rolled eggs, fried fish and fried bean curd were thawed in frying oil at 150°C-180°C and tested to investigate the following : 1) the change of the properties of frying oil, 2) the rise in internal tempetrature of the samples, and 3) the taste in color, appearance, crispness and flavor of the samples.
Deterioration of frying oil was the worst in thawing fried bean curd ; the best in croquettes. Deterioration of frying oil was much faster at 150°C, and color of the samples was more colorful at the same temperature, but appearance, crispness and flavor were not good. It means there was some relationship between deterioration of frying oil and the taste.
The data showed that thawing chiken balls, hamburg cutles in frying oil at 150°C was preferable and other samples at 180°C, and that the internal temperature of the samples must be kept at not less than 80°C.

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