Effect of pomegranate peel extract on lipid and protein oxidation in beef meatballs during refrigerated storage

• Concentrated lyophilised aqueous extract of pomegranate peel was prepared.
• The extract contained high phenolic content and showed high antioxidant activity.
• The extract was effective against protein and lipid oxidation in meatballs at 4 °C for a period of 8 days.

Antioxidant effect of pomegranate peel extract (PE) to retard lipid and protein oxidation was investigated in meatballs during refrigerated storage at 4 ± 1 °C. Concentrated lyophilised water extract of pomegranate peel was incorporated into freshly minced beef meat at 0.5% and 1% concentrations and compared with 0.01% butylated hydroxytoluene (BHT) as a reference and control (without any antioxidant). PE showed high phenolic content and antioxidant activity. In PE added samples, thiobarbituric acid reactive substances (TBARS) value, peroxide formation, loss of sulfhydryl groups and formation of protein carbonyls were lower than control (P < 0.01) after 8 days of storage. Sensory evaluation with respect to colour and rancid odour revealed that PE incorporation in meatballs prolonged the refrigerated storage up to 8 days. Addition of both 0.5 and 1% PE in meatballs reduced lipid and protein oxidation and improved sensory scores. These results indicated that PE was effective on retarding lipid and protein oxidation.