Effect of different temperature–time combinations on the quality and protein digestive properties of stewed beef tendons

This study investigated the effects of sous vide cooking and traditional high-temperature cooking on the texture, microstructure, protein structure and digestive properties of home made beef tendon using transmission electron microscopy, in vitro digestion and peptidomics. The adverse effects of heating on the muscle fiber structure and protein conformation of beef tendon gradually expanded with increasing temperature. In general, the degree of muscle fiber contraction, protein denaturation, and protein aggregation increases with temperature and time, with a concomitant decrease in protease action. The extent of protein digestion, and the yield of small fragments such as amino acids also decreased with increasing heating temperature and time. However, the solubilization of collagen makes the beef collagen more digestible after heating at 80°C, which indirectly leads to higher digestibility at 80°C. The combined peptide release and bioactive peptide results showed that the beef tendon heated at 60°C for 8 h produced the most peptides after digestion, and also produced four specific bioactive peptides, which were advantageous in terms of the number of digested products and bioactivity. The higher proportion of antioxidant amino acids in the product also gave the tendon heated at 60°C for 8 h a greater potential antioxidant capacity. As a result, beef tendon heated at 60°C for 8 h is more favorable for human digestion. This work may provide guidance for home cooking and dietary health. •Sous-vide processing improves protein digestion of beef tendons.•60°C favored digestion of structural proteins.•80°C favored digestion of collagen and inhibition of dipeptidy l peptidase.•The sample heated at 60°C for 8 h had maximum number of bioactive peptides.