Page:The story of milk.djvu/75

 1. From the test—fat-percentage—of the rich cream subtract the test desired.

2. From the test desired subtract the test of the milk used for diluting.

3. Divide the first difference by the second, and the result will be the number of pints (or pounds) of milk to be added for each pint (or pound) of the rich cream.

For instance, you may want to thin some 30% cream to 10% for making ice cream. The milk to be added is skim milk. Then:

1. 30 - 10 = 20.

2. 10 - 0 = 10.

3. 20 divided by 10 = 2. So for each pint of rich cream you may add 2 pints of skim milk.

Or you may wish to thin the 30% cream with whole milk, which has 4% butter-fat. Again:

1. 30 - 10 = 20.

2. 10 - 4 = 6.

3. 20 divided by 6 = 3-1/3. So you may add 3-1/3 pints of the whole milk to each pint of the 30% cream and still have a 10% cream.

Pasteurized Cream does not look as rich as raw cream, and fresh, sweet cream appears to be thinner than when it is 24 hours old and slightly ripened. So it is well, when buying cream, not to judge by appearances. Demand of the milkman that he furnish you cream of a certain percentage of butter-fat and see to it that you get what you pay for. If you have no Babcock tester the milk inspector will test the cream for you.

Whipped Cream.—For whipping, cream must be fairly rich, from 24% to 32%, and it must be cold. Fresh, sweet cream does not whip as readily as that