Negative impacts of in-vitro oxidative stress on the quality of heat-induced myofibrillar protein gelation during refrigeration

Abstract

To investigate the effects of pre-oxidized myofibrillar protein (MP) on stability of heat-induced MP gelation throughout 28 days of refrigeration, a hydroxyl radical generating system (10 μM FeCl3, 0.1 mM ascorbic acid, with 10 mM H2O2) was employed. Results demonstrated that an increase of carbonyl content followed a similar trend in both pre-oxidized and nonoxidized protein gels. Unexpectedly, pre-oxidized protein gels yielded increased (P < 0.05) hardness at 14 days of storage compared to the initial day of storage. The water holding capacity (WHC) had a significant positive correlation with gel hardness, percentage of immobile water, and T22, while having a negative correlation with carbonyl group content and T23 (P < 0.01). These results suggest that the pre-oxidation treatment increases the susceptibility of MP gel matrices to undergo oxidation and thus provides a better comprehension of the consequences that in vitro pre-oxidation treatments have on protein matrix systems.