Antioxidant effects of lotus (Nelumbo nucifera) root and leaf extracts and their application on pork patties as inhibitors of lipid oxidation, alone and in combination

Different antioxidant mechanisms of lotus root and leaf were exhibited against lipid oxidation. The effect of lotus root (LRE) and leaf (LLE) extracted with 50% ethanol exhibited high antioxidant activities. It also improved quality and/or oxidative stability of pork patties when extracts were applied individually (1%) or in combination (each 0.5%). The pork patties treated with either LLE or that with LRE exhibited significantly lower peroxide and 2-thiobarbituric acid reactive substances (TBARS) value than the control and patties with LRE. However, the lowest TBARS values were observed in patties with LLE alone from day 7 among the treatments. Patties treated with both LRE and LLE had the highest score in off flavor (P< 0.05). Hence, the combined effect of LRE and LLE was uncertain and the addition of 1% LLE in patties showed superior antioxidant activity during storage days with an adverse effect on quality properties, except for color