Fermentation is a natural process that has been going on in nature since before humans existed. For centuries we have been practicing food fermentation, knowingly or unknowingly. Every food culture in the world throughout history has been using fermentation in their food in some way. Bread making originated in Egypt 3500 years ago. Fermented drinks were being produced and consumed in Babylon(now Iraq) 7000 years ago. China is thought to be the birth place of fermented vegetables. A book called “Shu-Ching” written before 256 BC, mentions the use of “chu” a fermented grain product.
Scientifically or biologically speaking, fermentation is ‘an anaerobic process converting complex organic structures into simpler compounds’. From a culinary perspective, fermented food is food cured or aged. As the food gets broken down by micro organisms, the flavors within them become more prominent and strong.
One of the major reasons of fermenting food is preservation. Bio-preservatives-Alcohol, acetic acid and lactic acid are produced when food is fermented. Theses aid in preventing food from being spoilt. Also fermentation increases the nutrient value of the food in some cases
One of the remarkable qualities of milk is its ability of self-preservation. It can spontaneously foster a group of microbes that converts its sugars into acid and thereby preserve it for sometime from getting spoilt or harboring disease. Microbes also change the milk’s texture and flavor in desirable ways. Milk has a lot of nutrients, but the most important and readily available energy source is ‘lactose’ a sugar found almost nowhere else in nature. The microbes in the milk feed on this sugar, hence break it down converting it to lactic acid. Lactic acid retards the growth of most other microbes. They also make antibacterial substances but their main defense is a pleasant tartness, that also causes casein proteins to gather together in semi solid curds, which thickens milk. There are 2