Buttering cream is, as we have seen, a purely mechanical process. The quality of the cream is the deciding factor, and this means that the cream should be properly ripened and contain a preponderance of lactic-acid producing germs. The cream ripening is usually achieved with the help of a starter. A great advantage of sour cream buttering is that it produces, besides the butter, the refreshing and highly digestible buttermilk. The buttermilk coming out of modern sweet cream buttering tastes, like the butter, flat and cannot be used for human consumption.
True buttermilk is no longer on the market.
What is on the market under this name is not the result of the buttering process of sour cream. It is usually pasteurized skimmed milk, fermented with a laboratory culture. At the beginning of this century we still had experienced old country medical doctors. Most babies then could digest this milk. If in some cases the child could not take this milk, it was recommended to feed the child buttermilk from farm-produced butter.