Antioxidant efficacy of soybean cake extracts in soy oil protection.

The aim of this study was to evaluate the presence and possibility of extracting compounds with antioxidant properties of soybean cake to extend the storage stability of soybean oil. Results showed that the highest DPPH radical scavenging activity was observed for sample to solvent ratio 1:25 while extracting by 70% ethanol for 3 h). The most phenolic compounds equivalents (Gallic acid) was observed for sample to solvent ratio 1:25 while extracting by 70% methanol for 14 h. In addition, the soybean cake extract at concentrations of 50, 100, 150 and 200 ppm in soybean oil could significantly lower the peroxide, diene and p-anisidine values of soy oil during storage at 65 °C.