Effects of proteases inactivation on textural quality of yellow-feathered chicken meat and the possible mechanism based on myofibrillar protein

This study was undertaken to evaluate the impact of proteases inactivation on the textural properties of yellow-feathered chicken (YFC) meat and explore the underlying mechanism driving these changes. The results showed that firmness and shelf life of the YFC meat were significantly improved by the proteases inactivation pretreatment in a dose-dependent manner. Specially, the 40% and 60% residual protease activities were identified to yield textures comparable to the hot-fresh YFC meat. Hydration and water retention of the proteases inactivated YFC meat were also found to be enhanced. Further analysis of myofibrillar protein (MP) revealed that cross-linkages of MP were induced by proteases inactivation with 40% and 60%, evidenced by higher levels of disulfide, carbonyl-amine bonds and di-tyrosine. Additionally, the chemical changes in amino acid residues led to the sequestration of tryptophan residues and the formation of β-sheet structures, accompanied by increased turbidity and particle size of MP. Moreover, water holding capacity, lightness, digestibility and strength of the MP gel were found to be improved. The results would provide insights into potential application of proteases inactivation as a strategy to improve YFC textural quality.