Buttermilk (homemade)

There are many times that you may be making a recipe and realize
that it calls for buttermilk. If you don’t use it on a regular basis, chances are that you don’t have it in the fridge. Here is how to make your own buttermilk and it’s fast and easy!
Per one cup of buttermilk do the following:

1 cup milk
1 tablespoon vinegar or lemon juice

Let these sit together in a glass measuring cup for at least 10 minutes.

What exactly is buttermilk? Wikipedia (free online encyclopedia) says this, “Buttermilk is the liquid left over after producing butter from full-cream milk by the churning process. It has a slightly sour taste. It is quite popular as a refreshment in India. Many breads are made with buttermilk, and it is also used in creamy soups and sauces.

Most of the modern, commercially-available, "buttermilk" in supermarkets is not genuine buttermilk but rather cultured buttermilk that is milk to which souring agents (Streptococci bacteria) have been added to simulate the traditional product. The sour taste or tartness of "cultured buttermilk" is a result of a fermentation process in which the Lactococcus bacteria turn lactose into lactic acid. As the pH drops in this reaction the milk becomes tart. At this point, casein, a milk protein, precipitates as it is no longer soluble under acidic conditions, causing what is called clabbering or curdling. The acidity of buttermilk inhibits bacterial growth, and this gives it a long refrigeration life. This process can be repeated when making sour cream with slight alterations.”