A nonfermented imitation called “acidified
sour cream” is made by coagulating the cream
with pure acid. “Sour creams” labeled “low-
fat” and “nonfat” replace butterfat with starch,
plant gums, and dried milk protein.
Buttermilk Most “buttermilk” sold in the
United States is not buttermilk at all. True
buttermilk is the low-fat portion of milk or
cream remaining after it has been churned to
make butter. Traditionally, that milk or cream
would have begun to ferment before churning,
and afterwards the buttermilk would continue
to thicken and develop flavor. With the advent
of centrifugal cream separators in the 19th
century, buttermaking produced “sweet”
unfermented buttermilk, which could be sold
as such or cultured with lactic bacteria to
develop the traditional flavor and consistency.
In the United States, a shortage of true
buttermilk shortly after World War II led to
the success of an imitation, “cultured