Lacto-fermentation

Lore & Background

Chemical analysis of archaeological finds shows that milk fermentation had been used since prehistory; its first applications were probably a part of the Neolithic Revolution. Since milk naturally contains lactic acid bacteria, the discovery of the fermentation process was quite evident, as it happens spontaneously at an adequate temperature. The problem of these first farmers was that fresh milk is nearly indigestible by adults, so they had an interest to discover this mechanism. In fact, lactic acid bacteria contain the needed enzymes to digest lactose, and their populations multiply strongly during the fermentation. Therefore, milk fermented even a short time contains enough enzymes to digest the lactose molecules, after the milk is in the human body, which allows adults to consume it. Even safer was a longer fermentation, which was practiced for cheesemaking. This process was also discovered a very long time ago, which is proven by recipes for cheese production on Cuneiform scripts, the first written documents that exist, and later in Babylonian and Egyptian texts.

Reader's Guide

Lactic acid fermentation has had an important influence on some cultures' development, such as in Mongolia, where people often practice a pastoral form of agriculture. The milk that they produce and consume in these cultures is mainly mare milk and has a long tradition. Fermentation products of mare milk, like the slightly-alcoholic yogurt kumis, are central to cultural festivities such as the Mongolian lunar new year. Consuming white food in this festive context is a way to connect to the past and to a national identity, which is the Mongol Empire personified by Genghis Khan. During the time of this empire, the fermented mare milk was the drink to honor and thank warriors and leading persons. Although it eventually became a drink for normal people, it has kept its honorable meaning. The process was not properly described until the 19th century, when chemists including Joseph Louis Gay-Lussac, Justus von Liebig, and Louis Pasteur investigated it. Pasteur first described lactic acid as the product of a microbial fermentation in 1857, and he was the first to describe fermentation as a 'form of life without air.'

Did You Know?

• Lactic acid fermentation occurs in some bacteria and animal cells, such as muscle cells.
• Despite the name, milk is not required or created by this process.
• Heterolactic fermentation yields carbon dioxide and ethanol in addition to lactic acid.
• Louis Pasteur first described lactic acid as the product of a microbial fermentation in 1857.