🧀 Buttermilk

Buttermilk is the liquid left after cream is churned into butter. It is almost fat-free (usually less than 1% fat), but it retains proteins, lactose, minerals and much of the phospholipids from the fat globule membranes. If the butter was churned from soured cream, the buttermilk is slightly sour.

On traditional farms buttermilk was drunk, used in baking and fed to livestock. In many countries it is still important: in South Asia a similar drink is called chaas, and in West Africa people drink the sour buttermilk left after churning butter. In industrialised countries cream for butter is usually not soured, so the “buttermilk” sold in shops is more often made on purpose — by culturing pasteurised milk.

Buttermilk differs from kefir and clabbered milk in its origin: it is a by-product of buttermaking, not milk soured on purpose. Buttermilk is used as a drink, in baking (pancakes, soda bread, where the acid reacts with baking soda), for marinating meat and as a raw material for buttermilk powder and cheeses.