Buttermilk (From Wikipedia, the free encyclopedia)

Buttermilk refers to a number of dairy drinks. Originally, buttermilk was the liquid left behind after churning butter out of cultured cream. This type of buttermilk is now specifically referred to as traditional buttermilk. The term buttermilk also refers to a range of fermented milk drinks, common in warm climates (e.g., the Balkans, the Middle East, Turkey, Afghanistan, Pakistan, Nepal, India, Sri Lanka, Nicaragua and the Southern United States) where unrefrigerated fresh milk sours quickly, as well as in colder climates, such as Scandinavia, Ireland, the Netherlands, Germany, Poland, Slovakia, Slovenia, Croatia, and the Czech Republic. This fermented dairy product, known as cultured buttermilk, is produced from cow's milk and has a characteristically intense sour taste caused by lactic acid bacteria.

A quick version of buttermilk, known as acidified buttermilk, is used to make paneer. This version is simply cow's milk with a food-grade acid like lemon juice or vinegar added and left to sit for at least 10 minutes. That is when the milk has curdled.

Buttermilk can be drunk straight, and it can also be used in cooking. Soda bread is a bread in which the acid in buttermilk reacts with the rising agent, sodium bicarbonate, to produce carbon dioxide which acts as the leavening agent. Buttermilk is also used in marination, especially of chicken and pork, whereby the lactic acid helps to tenderize, retain moisture, and allows added flavors to permeate throughout the meat