Cheese ripening

Cheese ripening, alternatively cheese maturation or affinage, is a process in cheesemaking. It is responsible for the distinct flavour of cheese, and through the modification of "ripening agents", determines the features that define many different varieties of cheeses, such as taste, texture, and body. The process is "characterized by a series of complex physical, chemical and microbiological changes" that incorporates the agents of "bacteria and enzymes of the milk, lactic culture, rennet, lipases, added moulds or yeasts, and environmental contaminants". The majority of cheese is ripened, except for fresh cheese. Cheese ripening was not always the highly industrialised process it is today; in the past, cellars and caves were used to ripen cheeses instead of the current highly regulated process involving machinery and biochemistry. Some cheeses still are made using more historical methods, such as the blue cheese Roquefort, which is required to be ripened in designated caves in south-western France. However, with the invention of refrigeration in the 20th century, the process evolved considerably, and is much more efficient at producing a consistent quality of cheese, at a faster pace, and a lower cost (depending on the type of cheese). After the initial manufacturing process of the cheese is done, the cheese ripening process occurs. This process is especially important, since it defines the flavour and texture of the cheese, which differentiates the many varieties. Duration is dependent on the type of cheese and the desired quality, and typically ranges from "three weeks to two or more years". Ripening is influenced by a variety of factors, ranging from the microflora to the curd, and others. The enzymatic process is the most crucial process for all cheeses, although bacteria play a role in many varieties. The most important agents in this process include the following elements: Rennet, or a substitute for rennet starter bacteria and associated enzymes milk enzymes second starter bacteria and associated enzymes non-starter bacteria Each of these factors affects the cheese-ripening process differently, and has been the subject of much research.