Efficacy of Pomegranate (Punica granatum L.) Peel Extracts in Suppressing Oxidation of White Coconut Oil Used for Deep Frying

Abstract

The effect of pomegranate (Punica granatum L.) peel extracts on the stability of white coconut oil during deep frying (180 ± 5 °C/10 min) was determined. Antioxidative constituents present in the peel of pomegranate varieties Nayana, Daya and Nimali were extracted into acetone and incorporated into white coconut oil (WCO) at 2 % (w/w) level. The WCO samples containing peel extracts were used to fry standard sized potato pieces. The oil samples were subjected to three frying cycles. After each frying cycle, oil samples (10 mL) were drawn and the level of oxidation was assessed using peroxide value (PV), thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and conjugated trienes (CT). α-Tocopherol was used as the reference antioxidant and oil devoid of any additive was used as the control. Results revealed that pomegranate peel extracts from the three varieties tested are potent antioxidants that can effectively suppress oxidation and stabilize WCO during deep frying.