The dynamic changes of ohmic cooking on pork meat oxidation and digestion in vitro

In order to investigate the effects of ohmic ( OH) and waterbath ( WB) cooking on lipid and protein oxidation, protein surface hydrophobicity, aggregation and the changes of pepsin, trpsin and α-chymotrypsin digestion rate in vitro of cooked meat samples at the same endpoint temperatures ( EPTs, range, 20~100 ℃) were evaluated.The results indicated that as the EPTs was increased, the values of protein carbonyl of cooked meat samples was decreased previously and then increased, whereas the values of trpsin and α-chymotrypsin in vitro was decreased. The OH-cooked samples had significant ( p < 0.05) lower protein surface hydrophobicity than that of the WB-cooked ones at 40 ℃.The OH-cooked samples had significant ( p < 0.05) higher trpsin and α-chymotrypsin digestion rate in vitro than WB-cooked ones at 20 ℃.The OH-cooked meat samples had significant ( p < 0.05) lower carbonyl, pepsin digestion rate in vitro and higher trpsin and α-chymotrypsin digestion rate in vitro than WBcooked ones at 60 ℃.The OH-cooked meat samples had significantly ( p < 0.05) lower TBARS values than WB-cooked ones at80 ℃, and no significant difference ( p > 0.05) was detected between OH and WB-cooked samples on other parameters. The significant negative correlation was observed in protein aggregation, surface hydrophobicity and pepsin digestion rate in vitro ( p < 0.05) . Therefore, the ohmic cooking could save 1/2~5/6 total cooking time, and there was no obvious difference in all detected parameters of oxidation and protein digestion in vitro between OH and WB-cooked samples.