摘要
To determine the degree of oxidation in vegetable oil, a photochemical method using the electron spin resonance （ESR） spin trapping technique was developed, and the results were compared with those obtained using conventional peroxide-value （PV） and acid-value （AV） methods. Vegetable oil heat-treated were subjected to short UV illumination, and the produced alkyl-oxyl radicals were identified and quantified using the ESR spin trapping technique. ESR signal intensity was used as an indicator of oil oxidation, which monotonically increased as a function of the heat-treatment time. Commercially, available oils were selected and analyzed. The results were compared with those obtained using the PV and AV methods. The present method displayed some analogies with the PV method at least in the early stage of heating. Overall, the present method had highly sensitive and capable of detecting early-stage oxidation in vegetable oil.
