Substituting sodium by various metal ions affects the cathepsins activity and proteolysis in dry-cured pork butts

Salt contents and compositions are crucial parameters to enzyme activity and might even affect the proteolysis and quality of dry-cured meat. However, the metal ions significantly vary with geographic origin, which would be a determinant in the dry-cured meat manufacture. Therefore, the main salt compositions of KCl, CaCl2, MgCl2 and ZnCl2 were therefore used to partially substitute NaCl while additionally assessing and regulating their function during the dry-cured pork butts processing. Physiochemical properties, cathepsins activity, proteolysis and sensory evaluation were investigated. The results indicated that partial substitution of sodium prevented the dehydration, and accelerated the pH reduction. CaCl2 and MgCl2 partial substitution moreover exerted some promoting effect on cathepsin activity whereas ZnCl2 was a subtle inhibitor. The proteolysis index of CaCl2 and MgCl2 substitution were superior to the rest. The metal ions partial substitution reduced saltness, while the presence of KCl and MgCl2 enhanced bitterness. Further correlation analysis was performed to better understand the interactions between those parameters. •Salts, endogenous enzymes and proteolysis considerably affect dry-cured meat quality.•KCl, CaCl2, MgCl2 and ZnCl2 were used as partial NaCl substitution.•Partial metal ions substitution prevented the dehydration, and affected pH decline.•Partial metal ions substitution affected cathepsin activities and proteolysis.•Correlation analysis was performed to further elaborate the parameters interactions.