Evaluation method of deterioration of frying oil and selection method of frying oil that is hard to deteriorate

摘要

PROBLEM TO BE SOLVED: To suggest an indicator for appropriately and rapidly evaluating degradation of frying oil and to provide a method for evaluating degradation of frying oil using the indicator.SOLUTION: A first method of the present invention is a method for evaluating degradation of frying oil in which the 3-methyl-2, 4-nonane dione in frying oil is used as an indicator of degradation of the frying oil, the frying oil containing soybean-derived fat in 20-100% by mass. A second method of the present application is a method for selecting frying oil which is difficult to become degraded, the method including the steps of: (i) heating at least two different types of frying oils containing soybean-derived fat in 20-100% by mass, under at least one condition selected from temperatures of 150-220°C and 5-80 hours; (ii) measuring the contents of the 3-methyl-2, 4-nonane dione in the frying oils after heating; and (iii) comparing the contents of the 3-methyl-2, 4-nonane dione and determining the frying oil which contains the 3-methyl-2, 4-nonane dione in the smaller amount to be the frying oil which is more difficult to become degraded.SELECTED DRAWING: None