Influence of different types of fermentation-produced chymosin on quality of soft cheeses

Abstract

The disadvantage of soft cheeses is their short shelf life. In soft cheeses with a high moisture content, proteolysis occurs at a high rate, as a result of which the cheeses quickly overripe. The main proteolytic agent in soft cheeses is the milk-clotting enzyme (MCE). Increasing the shelf life of cheeses can be achieved by using MCE types having low proteolytic activity (PA). We have studied the effect of MCE based on different types of fermentation-produced chymosin: Chy-max® Extra (bovine chymosin), Chy-max® M (camel chymosin), Chy-max® Supreme (“modified” chymosin) on the dynamics of proteolysis in soft cheeses and related changes in the structure of cheeses during their storage. All 3 types of studied MCEs have different levels of nonspecific PA. The higher the level of nonspecific PA of the used MCE, the higher the rate of the proteolysis process in the resulting cheeses. Increasing the dose of MCE also increases the rate of proteolysis in cheeses. To increase the shelf life of soft cheeses, which depends on the period of preservation of a dense consistency, it is promising to use MCE with low PA based on camel chymosin (Chy-max® M) and “modified” chymosin (Chy-max® Supreme).