Effect of oxidation on finely segmented products of snakehead: Digestibility and microstructure

The present study was performed to investigate the digestive profiles of snakeheads' belly muscles (BM), tail muscles (TM) dorsal muscles (DM), and eye muscles (EM), with further explorations of relevant factors. Kinetic models were adopted to describe the digestion process with crucial parameters. BM showed the highest digestibility and digestive rate, followed by DM, TM, and EM. Meanwhile, the BM showed the lowest hardness and springiness among the four muscles observed by texture Profile Analysis. The oxidation during storage promoted the digestion of muscles as well. The deformation due to oxidation caused a growth in cooking loss, TVB-N values, and gap rates of muscles, making the muscles more sensitive to digestive enzymes. The varying conformations of myofibrillar proteins (MP) led to the devious digestibility: MP obtained from BM held the highest release level of free amino groups because of a loosened and disordered structure with the lowest denaturation temperature. •The belly muscles of snakehead showed the highest digestibility and digestive rate.•The belly muscles showed the loosest microstructure with the highest gap rate.•Fresh muscles had the largest proportion of free water with the strongest mobility.•Myofibrillar proteins from the belly were most sensitive to thermal denaturation.•Unstable conformation of oxidative proteins led to the rising digestibility of muscles.