Buttermilk is the liquid left over after producing butter from full-cream milk by the churning process. It has a slightly sour taste, which is usually pleasant when people are accustomed to it. Most of the modern, commercially-available, "buttermilk" in Western supermarkets is not genuine buttermilk but rather cultured buttermilk , that is milk to which souring agents (Streptococci bacteria) have been added to simulate the original product. Many breads are made with buttermilk and are exceptional in soups and sauces. For breads made solely with grains, buttermilk may contain ammounts of calcium from its dairy products, such as nonfat dry milk powder.
