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 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