Temperature-dependent in vitro digestion properties of isoelectric solubilization/precipitation (ISP)-isolated PSE-like chicken protein

The effects of various heating strategies (72 degrees C-20 min, 100 degrees C-60 min) on the digestibility of isoelectric solubilization/precipitation (ISP)-isolated pale, soft, exudative (PSE)-like chicken protein in an in vitro simulated gastrointestinal model were studied. Untreated PSE-like meat protein was used as the control. The hydrophobic groups were much more exposed in ISP-isolated protein than in the control protein, and the difference diminished after heating. The results of SDS-PAGE analyses and digestion kinetic parameters show the ISP isolates had higher digestibility than the control group when heated at 72 degrees C for 20 min (P>0.05), but there was no significant difference between the 100 degrees C heated groups (P 0.05). Additionally, all ISP-isolated groups showed higher peptide abundance than the control groups. In summary, heating at 72 degrees C for 20 min is beneficial to increase the digestion properties of ISP-isolated PSE-like chicken protein, but its gel properties are weaker than those of protein heated at 100 degrees C for 60 min.