ABSTRACT
Various fermented products originated from spontaneous fermentation of a raw material, such as milk, meat, or vegetables. Initially, the main focus was on preservation of the raw material. Raw milk, for example, will be susceptible to microbial spoilage at room temperature; the milk will rapidly acidify, due to the activity of lactic acid bacteria. Apart from preservation, fermented products also develop distinctive tastes and smells that are widely appreciated. Over time, in the process of fermentation many variations developed, partly purposely and partly spontaneously and in relation to the technology used. Their nature depends very much on the type of raw material used, on its pretreatment, on the temperature (climate), and on the conditions of fermentation. This practice is still common in various parts of the world: part of a spontaneously fermented product is transferred deliberately into a new batch of raw material in order to maintain or even strengthen it. This principle is the basis for controlled preservation, sustainable and safe, many times resulting in an attractive flavor, although the process is not controlled.
