Page:The story of milk.djvu/105

 Salting.—During this working process salt is added and thoroughly distributed and worked in. About half an ounce of salt is used for a pound of butter.

Composition of Butter.—When finished, the butter ought not to contain more than 12% to 15% of water, and there should be at least 80% of butter-fat. If all the butter-fat originally in the milk could be taken out in the butter, 100 lbs. of 4% milk should yield 4.88% (4.88 lbs.) of butter with 82% butter-fat. But a little is lost in the skim milk and more in the buttermilk, which usually contains 1/2% fat, so that about 4-1/2 lbs. is all the butter that can be expected from 100 lbs. of milk.

Overrun.—Creamery men are much interested in the "Overrun" which means the increase from the churn over the amount of fat in the milk. For instance, if a quantity of milk containing 100 lbs. butter-fat as shown by the Babcock Test produces 114 lbs. of finished butter, the overrun is 14%. The buttermaker who gets the largest overrun by reducing the loss of butter-fat in the skim milk and the buttermilk to a minimum, keeping the percentage of water in the butter just below 16%, and yet producing high scoring butter, is considered most efficient.

Packing.—For the market, butter is packed in tubs or stone jars. Or it is molded in neat one-pound bricks and wrapped in parchment paper.

Sweet Butter.—Real "sweet" butter is churned from fresh, sweet, unsoured cream. But usually the name is given to the unsalted and uncolored butter that many people relish. Without the salt it does not keep as well as ordinary butter, and must be eaten quite fresh. Well-made salted butter will keep for months