Effects of reheating methods on oxidation and digestibility characteristics of precooked braised chicken during in vitro digestion

This study investigated the effects of microwave reheating (MW), water boiling reheating (WB), and steaming reheating (ST) on the oxidation and digestibility characteristics of precooked braised chicken (PBC), using a non-reheated control (C). Oxidation markers increased after all reheating treatments; the ST group preserved total sulfhydryl and carbonyl content closest to the C group, indicating minimal oxidation. Following in vitro digestion, reheated samples displayed reduced digestibility as measured by crude protein digestibility, SDS-PAGE profiling and peptide molecular weight distribution. The digestibility of crude protein and the degree of hydrolysis in the ST group (74.40% and 37.39%) were most similar to those of the C group (76.69% and 40.71%). Distribution analysis of digestion products revealed that the ST treatment outperformed the other reheating methods. ST treatment emerged as a viable reheating method for maintaining protein digestibility in precooked meat products. • Steaming preserves protein digestibility better than microwave or boiling. • Minimal protein oxidation occurs in steaming (lowest carbonyls, highest sulfhydryl). • INFOGEST digestion shows steaming causes protein hydrolysis close to control. • Microwave and boiling cause greater oxidation, decreasing protein digestibility. • Oxidation of reheated chicken protein inversely correlates with digestibility.