Study of proteolysis and lipolysis of probiotic Lighvan cheese

The aim of this study was to characterize proteolysis and lipolysis activities of probiotic Lighvan cheese at 5, 25, 45 and 60 days of ripeness. Levels of proteolysis were assessed in the cheese from measurements of the following: WSN(%), NPN(%), RI(%) and NPN/TN(%) and levels of lipolysis were assessed from measurements of: ADV (%) and FFA(%). The effect of time on proteolysis and lipolysis activities of probiotic Lighvan cheese was determined significant (p<0.05). Values of the following increased continuously until the end of the ripening period; WSN(%), NPN(%), RI(%), NPN/TN(%), ADV (%) and FFA(%) but total nitrogen decreased throughout the duration of the 60-day storage time. The addition of B. lactis had a significant (p<0.05) effect on the proteolysis and lipolysis characteristics of Lighvan cheese and despite an increase in RI, the depth of ripening was low and a low value was determined for NPN/TN %, an indication that peptidase activity was very low. From the results of this study in can be concluded that in cheeses ripened in brine, a significant part of the ripening bi products are transferred into the brine so their effect on the sensory properties of the final product is therefore limited. The rate of proteolysis and lipolysis was slow because environmental conditions such as salt and lactic acid concentration can affect the proteolytic and lipolytic activities of the indigenous microbial enzymes in Lighvan cheese.