Abstract
To study the effects of frying materials on frying oils properties, the following raw materials were applied. Beef of Australian's D-rump part, broiler's breast-muscles at Kagoshima prefecture. sweet pepper of produced at Miyazaki prefecture and eggplant of Senryou-2 produced at Kouchi prefecture were cut square about 30×40×3mm. The raw materials were fried in additive-free rapeseed oil at 180°C, and the obtained oil was measured by the coloration, the acid value(AV), the carbonyl value (COV), the anisidine value (An. V), the conjugated diene content and the viscosity. The following results were obtained.
1) It was suggested that the frying oils colored strongly in the case of frying protein rich foods and dispersing material's settling in the frying oils.
2) The conjugated diene content and viscosity of frying oils were lower than those of the heating oils and the heating oils with aeration as control. Therefore, it was estimated that frying materials and frying effected decrease of these values.
3) It was assumed that the carbonyl compounds formed in deteriorated frying oil, changed to the browning pigments by the amino-carbonyl reactions with the amino compounds from fried materials. Therefore, it was estimated that the carbonyl compounds were not measured as COV and An. V.
