ripened and churned, the product will be identically the same as natural buttermilk from ripened cream.
Ripening.—For best result the milk should be pasteurized,
not necessarily as thoroughly as for starters,
but sufficiently so as to destroy all obnoxious bacteria
and give those introduced through a pure culture
starter a chance to grow. Buttermilk may, however,
also be made from good, clean, unpasteurized milk of
good flavor. Whether pasteurized or not the milk is
set to ripen with from 5 to 10% starter at a temperature
of from 65 to 75°. The preparation of starters is described
under "Bacteria" and the ripening of the milk
for "buttermilk" is essentially the same process (see
also under Ripening of cream for butter). When ripened
to the desired acidity,—say .5% to .6% by the
acid test,—stop further fermentation by thorough
cooling.
Breaking up the Curd.—After cooling, the ripened
milk may be broken up fine and if vigorously shaken
or "churned" it will remain smooth and creamy. Otherwise
it may separate into curd and whey. If churned
long enough for the butter to form, it becomes absolutely
identical with real buttermilk. But, for all
practical purposes, a vigorous shaking for a few minutes
is enough.
Thick Milk.—"Thick Milk" as eaten in Scandinavia
is made in the same way as commercial buttermilk,
except that the milk—rich whole milk—is set to
ripen in the bowl in which it is to be served. Instead
of being churned or stirred, it is left thick, to be served
as a pudding, like Junket made from sweet milk. The
rich layer of cream that forms on top is excellent.
"Thick Milk" is eaten plain with the oatmeal for