The effects of natural antioxidants on oxidative processes and metmyoglobin reducing activity in beef patties

The effects of antioxidants on oxidative processes and metmyoglobin-reducing activity in beef patties were investigated in two experiments. In the first experiment colour, colour stability, TBA values and MetMb-reducing activity were measured during storage, at 2 degreesC, of raw beef patties treated with four antioxidants (resveratrol, carnosine, quercetin and rutin) at two concentrations (110 and 550 mumol/kg(meat)). In the second experiment the method of application of resveratrol was tested further. The storage period and antioxidant treatment affected colour, colour stability and TBA values. The colour-stabilising effect of the antioxidants was in the following order resveratrol>quercetin>rutin>carnosine. The performance of resveratrol was affected by the method of application. Resveratrol gave the highest protective effect against lipid peroxidation. Carnosine acted as a pro-oxidant under the specified experimental conditions. MetMb-reducing activity remained relatively stable during storage. It was concluded that the lack of NADH and not the loss of MetMb enzymatic activity was the factor limiting the MetMb-reducing activity in beef patties and, consequently, the factor dictating the colour and colour stability of beef patties. (C) 2002 Published by Elsevier Science Ltd.