Page:The story of milk.djvu/42

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.

Babcock test outfit

The Babcock Test.[1]—By treating a sample of milk with strong sulphuric acid the butter-fat is liberated as an oil. By subjecting the mixture to centrifugal force the light butter oil is separated from the rest of the*

  1. The Babcock Test is operated as follows: When the milk has been thoroughly mixed and a true sample has been taken the pipette is filled to the mark by sucking the milk into it until it stands a little above the mark on the stem, then quickly placing a dry finger over the end of the pipette and allowing the milk to escape until it just reaches the mark. The quantity thus measured off is 17.6 c.c. The pipette is then emptied into the test bottle by placing the point in the neck and allowing the milk to flow slowly down the inside of the neck, taking care not to lose any of the milk. Blow the last drops out of the pipette into the bottle. The measuring glass, holding 17.5 c.c., is filled to the mark with sulphuric acid of a specific gravity of 1.82 to 1.83 and this is poured into