Effects of storage conditions on oxidative stability of soybean oil

Abstract

Abstract: Soybean oil in the presence or absence of 200 µg g −1 tert-butyl hydroquinone (TBHQ) was subjected to accelerated oxidative storage at 60 • C for 10 days or stored at room temperature for 12 months. Tocopherol contents of the oil decreased, whereas the headspace volatiles and peroxide values (PV) increased as the storage time increased. During accelerated storage, TBHQ was effective in retarding the formation of hydroperoxides and headspace volatiles in the oil. TBHQ also protected tocopherols, especially α-tocopherol, from oxidation. During long-term room-temperature (LTRT) storage, the changes in PV between the oils with and without TBHQ were similar, but the oil with TBHQ had lower headspace volatile contents than that without TBHQ. Headspace volatile analysis was more suitable than PV measurement for predicting the oxidative stability of soybean oil during LTRT storage. The contents of hexanal or (E)-2-heptenal in the oil at 1-5 days of accelerated storage could be used to predict those of the corresponding compound in the oil at 0-4 weeks of LTRT storage