Originally, buttermilk was the fluid remaining after cream was churned into butter. Buttermilk has been drink and used in American cooking since colonial times.
Dutch settlers in New York had it with their breakfast.
Today, cultured buttermilk is made by adding acid lactic bacteria to milk, usually low-fat (1% milk fat) or fat free milk.
Lactic acid is a byproduct naturally produced by fermenting lactose.
As the natural bacteria in the milk produce lactic acid at room temperature, the pH of the milk decreases and the casein precipitates, which cause the curdling or clabbering.
And that is why buttermilk is thicker than plain milk.
Buttermilk is used in buttermilk biscuits and certain other baked goods primarily for flavor, although it can whiten, tenderize and leaven in some cases.
As a drink, buttermilk is tangy, highly flavored, and very nutritious. Like cream, buttermilk is thick and full bodies and like wine it fills the mouth with lasting, tart flavor.
The fluid of buttermilk
