Exogenous Enzymes in Cheese Making: An Overview

The flavour in mature cheese results from a complex series of biochemical events that occur in the curd during ripening. More than 500 varieties of cheese are produced in the world, and each of them possesses its typical sensory characteristics. Flavour depends on milk variety, starter bacteria used in cheese-making and ripening. Amino acids and Free Fatty Acids (FFA) act mainly as precursors of a series of catabolic reactions, still not well understood. These reactions lead to the production of aroma compounds such as esters, fatty acids, aldehydes, alcohols, ketones, hydrocarbons, lactones, and sulphur. Enzymes involved in all these processes are derived from milk, Lactic Acid Bacteria (LAB), Non-Starter Lactic Acid Bacteria (NSLAB), rennet, or fungi. In cheese industrial production, the milk pasteurization process leads to the removal of endogenous bacteria; therefore it is necessary to add exogenous enzymes to enrich and standardize cheeses flavour. Here, we reviewed some exogenous enzymes used in industrial cheeses production or which have interesting potential in cheese making and ripening.