Abstract
Relationships between the flavor evaluation procedure and objective chemical tests for measuring oxidative deterioration in stored food fats were investigated. These chemical tests involved the measurements of peroxide value, TBA test, and carbonyl value, parts of which were modified for simplicating the procedure. Fried rice cakes, which are typical fat-bearing foods in Japan, were chosen as the testing media. They were fried with soybean oil, safflower oil, olive oil, and lard at 240 °C respectively, as well as with these oils which had been heated at 240 °C for 2 h. Then these fried rice-cakes were aged under various conditions, namely, in dark at 24 °C, 38 °C and 60 °C, in light at 25 °C, and in sunlight at room temperature. The development of rancidity in these fried rice cakes was measured by means of chemical tests and sensory evaluation by an experienced testing panel. The results obtained by these chemical tests were correlated somewhat with the flavor scores. Especially carbonyl value based on 2, 4-dinitrophenylhvdrazone method showed a good correlation with the flavor score. Several weak points of these chemical tests employed in this report were discussed.
