Abstract:

Chicken breast myofibrillar protein was oxidized to different extents after 24 h of incubation in hydroxyl radicalgeneration
systems (10 μmol/L FeCl3, 0.1 mmol/L ascorbic acid, and 0 to 5 mmol/L H2O2) and physico-chemical properties
of the different oxidation products and properties of heat-induced gels prepared from them were comparatively investigated.
The results showed that carbonyl content steadily increased and thiol group content declined with increasing H2O2
concentration, indicating continuous oxidation of the myofibrillar protein. Heat-induced gel hardness increased significantly
as the concentration of H2O2 increased from 0.00 to 0.10 mmol/L while protein solubility and surface hydrophobicity
declined. When H2O2 concentration increased up to 5 mmol/L, protein solubility as well as gel hardness and springiness
significantly decreased (P ＜ 0.05), whereas the converse trend was observed for surface hydrophobicity. These results
suggest that mild oxidation could improve the heat-induced gel formation of myofibrillar protein.

Key words: oxidation, myofibrillar protein, gelation, physico-chemical properties