The Tester, Acid, Acid Measure, Test-bottle, And Thermometer at Bottom; Filling The Pipette on Right; Adding The Acid And Measuring The Fat at Top

The Tester, Acid, Acid Measure, Test-bottle, And Thermometer at Bottom; Filling The Pipette on Right; Adding The Acid And Measuring The Fat at Top

The Babcock tester shows only the amount of pure butter-fat in the milk. It does not tell the exact amount of finished butter which is made from 100 pounds of milk. This is because butter contains a few other things in addition to pure butter-fat. Finished and salted butter weighs on an average about one sixth more than the fat shown by the tester. Hence to get the exact amount of butter in every 100 pounds of milk, you will have to add one sixth to the record shown by the tester. Suppose, for example, you took one sample from 600 pounds of milk and that your test showed 4 per cent of fat in every 100 pounds of milk. Then, as you had 600 pounds of milk, you would have 24 pounds of butter-fat. This fat, after it has been salted and after it has absorbed moisture as butter does, will gain one sixth in weight. As one sixth of 24 is 4, this new 4 pounds must be added to the weight of the butter-fat. Hence the 600 pounds of milk would produce about 28 pounds of butter.