Abstract
Change of BHT added to soybean oil by ultra violet light irradiation was investigated. Soybean oil containing BHT was irradiated by ultra violet light at 50°, and residual BHT and peroxide values of soybean oil were followed. The amount of BHT added rapidly decreased during the induction period of increase of peroxide value. After the induction period, almost all of BHT disappeared. Decomposition products of BHT were extracted with acetnitrile and identified by thin layer chromatography and gas chromatography with 3, 5-di-tert-butyl-4-hydroxy-benzaldehyde (BHT-ald), 3, 5-di-tert-butyl-4-hydroxy-benzyl alcohol (BHT-alc), 3, 5, 3', 5'-tetra-tert-butyl-4, 4'-dihydroxy-1, 2-diphenylethylene (BE), 3, 5, 3', 5'-tetra-tert-butylstilbenequinone (SQ), and 2, 6-di-tert-butyl-benzoquinone (BQ), which were prepared by chemical oxidation of BHT. Among the products of irradiation of BHT, BE, BHT-alc and BQ still retained respectively 64%, 56% and 23% antioxidative activity of the original BHT.
