Oxidative Stability of Soybean Oil Supplemented with Pod Coat Extracts of Cluster Bean

Abstract

The aim of present work was to determine the potency of phenolic extracts from cluster bean pod coats in improving shelf life of soybean oil. Pod coats of cluster bean were extracted with three solvents (acetone, ethylacetate and chloroform). Crude soybean oil samples were stabilised by adding different extracts at 1000 and 2000 ppm concentration and effect of addition of these extracts on oxidative stability of crude soybean oil at 50°C was observed. Rate of oxidative degradation of crude soybean oil was lowest in the sample treated with acetone extract (2000 ppm). The value of various oxidative quality parameters of crude soybean oil supplemented with acetone extract (2000 ppm) after 28 days of incubation are peroxide value (26.77 meq/kg oil), free fatty acids content (2.637%), p-anisidine value (25.18), TOTOX value (78.72), conjugated dienes (28.47%), conjugated trienes (13.97%) and TBA value (31.59 meq malonaldehyde/g). Results of present study indicate that pod coat extracts of cluster bean possess remarkable antioxidant potential and considerably lowered the rate of oxidative deterioration of crude soybean oil.