Cheese | Starter Cultures: General Aspects

This article addresses general concepts surrounding the use of starter cultures in cheesemaking. Starter cultures are essential to the manufacture of many cheese types. Whether prepared from the natural flora of milk, propagated as cultured whey, or selected from a preserved collection of defined single strains or undefined mixtures, starter cultures must be matched to the cheese type being made. Cheese starter cultures are predominantly composed of lactic acid bacteria, although other bacteria and yeasts may also be involved. In cheese manufacture, the primary role of starter cultures is the production of lactic acid from lactose at a predictable and controlled rate. Controlling acid production during cheesemaking is key to achieving control over curd pH, moisture, and lactose level. These factors in turn have a major influence on the microbial, chemical, and biochemical environment of the maturing cheese. Metabolism by starter cultures and the enzymes they produce contribute to the development of cheese flavor. The preparation and use of bulk starter cultures and culture concentrates are discussed.