Effect of salt and chymosin on the physico-chemical properties of feta cheese during ripening

The physico-chemical properties during ripening of Feta cheese made from bovine milk were monitored at 7-d intervals for 63 d. Samples were analyzed for moisture, fat, protein and ash contents, salt uptake, pH, and hardness. Three percentages of salt in brine (8, 15, and 18%) and three concentrations of double-strength chymosin (0.5, 1, and 2.5 ml/10 L of milk) were investigated. Salt had a significant effect on moisture, uptake of salt, pH, and hardness. Results indicated that higher percentages of salt in brine developed a harder cheese with higher salt content and higher pH values but lower moisture content. High rennet concentration had a significant effect on the uptake of salt. Increasing the concentration of rennet gave a softer cheese with higher salt content. Rennet level had no significant effect on the moisture or protein contents or pH of the cheese.