Study on stability of wheat germ oil and lipase activity

The purpose of the present study was follow the influence of periodical storage (at room temperature, 25-30°C), on the stability of oil including primary and secondary oxidation, total oxidation as well as conjugation. Color intensity at 430 nm of the oil samples was also evaluated to show changes of color during periodical storage. It was generally found peroxide value, panisidine, total oxidation, conjugated diene and conjugated triene gradually proportionally increase at storage periods of 1,2,3,4,5,6 and 7 days.The course of lipase inhibition was followed in wheat germ during periodical heat exposure, and it was found that the lipase activity was suppressed by exposure to temperature of 70°C for 30 min. to keeping the majority of oil triglycerides in the intact condition. Samples of wheat germ oil were analyzed individually in triplicates, and the results were reported as mean ±SD. Statistical significance of the differences between mean values was assessed by one-way ANOVA.