Effect of curing agents and water activity on pork muscle and adipose subcutaneous tissue lipolytic activity

Abstract

The effect of chemical agents (salt, nitrate, ascorbic acid and glucose) and water activity (aw) on pork muscle and adipose subcutaneous tissue upases and esterases has been studied. In muscle, salt above 20 g/L strongly inhibited neutral lipase and acid esterase but activated acid lipase. In adipose subcutaneous tissue, 7.5 g/L salt inhibited basic lipase and strongly inhibited acid esterase (around 40% recovery). Nitrate, ascorbic acid and glucose had a negligible or slightly inhibitory effect. A decrease in muscle aw affected both neutral and basic lipase down to negligible activities at aw=0.80. A decrease in adipose tissue aw (down to 0.66) affected both acid and neutral esterase (around 40 and 65% of recovered enzyme activity, respectively). An in-vitro study representing three stages of the dry-curing process revealed that muscle acid lipase and acid esterase might play an important role throughout the process, whereas the rest of the studied enzymes in muscle would be less important. Neutral lipase might be the most important enzyme in the subcutaneous adipose tissue lipolysis of dry-cured ham.`