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 proper sourness when churned, the buttermilk will be of a pleasing taste and flavor. Its thickness will of course depend upon the amount of water, if any, added to the cream in the churn during the buttermaking. If the buttermilk is to be used for human food care must be taken not to dilute it too much.

Cooling Essential.—If buttermilk is left to stand for hours in a warm room, fermentation goes on and may soon spoil the buttermilk by making it sloppy or bitter. It should therefore be cooled at once when drawn from the churn; if kept in ice water it may remain in fine flavor for several days. Well taken care of it is not only a pleasing and refreshing drink but eminently healthful. In cooking, too, it can be used to advantage.

Commercial Buttermilk or Cultured Milk is simply carefully soured milk. It can be made at home from fresh milk either whole or skimmed or partly skimmed. Partially skimmed milk containing from 1% to 2% butterfat is plenty rich enough and even better for most purposes than whole milk. The essential qualities of good buttermilk depend upon the proper ripening of the cream or milk, the development of a pure "breed" of healthful bacteria in a clean field free from weeds. Such a plantation or "culture" may be grown in milk as well as in cream. Its function is to turn the sugar of milk into lactic acid under the development of pleasing flavors and whether the butter-fat is removed by the separator or by churning makes little difference. In natural buttermilk there is always a little butter-fat—at least 1/2%—left, mostly in the form of fine granules, too small to be retained in the butter. If the same amount of butter-fat is left in skim milk and that is