Effect of type of coagulant and addition of stored curd on chemical, rheological and microstructural properties of low-moisture mozzarella cheese

Low-moisture Mozzarella cheese (LMMC) was manufactured in a dairy factory by stretching fresh curd in hot water, with the addition of 0–30% commercial curd (stored curd) purchased as a semi-finished product. Two commercial fermentation-produced camel chymosins, CC-M and CC-S, were employed as coagulants. The chemical, rheological and microstructural properties of LMMC were assessed during storage. The results demonstrated that cheese composition was not significantly influenced by curd addition. The use of CC-S promoted a slight increase of fat matter with respect to the CC-M samples because of the higher proteolytic specificity and clotting activity of the CC-S enzyme. A higher extent of proteolysis was found in LMMC manufactured with CC-M. The textural properties evaluated during storage revealed an increase in meltability, adhesiveness and springiness over time. The amount of added curd had only a minor effect. The melting behaviour was significantly influenced by proteolysis during the 35-day storage period. Overall, the proteolysis during aging was the most impactful factor affecting the properties of LMMC.