76 BOARD OF AGRICULTURE. [P. D. 4. 



come to a practically unanimous verdict that for simplicity, 

 safety and economy there is no other method of safeguarding 

 the healthfulness of the milk supply which compares with 

 proper pasteurization. 



Standards of Cleanliness. 

 The civilized man is clearly distinguished from the savage by 

 the care he exercises in providing clean food, and there is per- 

 haps none of our food products regarding the cleanliness of 

 which we are more particular than that of milk. This is per- 

 haps in part due to the color of milk and the distinctness with 

 w^hich any foreign matter in milk stands out against the white 

 background. Because of the sensitiveness of the purchasing 

 public, dirt in milk is usually present in very slight amounts, 

 approximating 1 part in 1,000,000. Such slight amounts prac- 

 tically defy ordinary analytical methods, but early in the pres- 

 ent century attention of milk inspectors was generally drawn to 

 a device called the sediment test. This was a simple device for 

 removing the foreign matter from a given sample of milk — 

 usually a pint — and presenting it to the eye upon a back- 

 ground of white cotton. For a time this test quite captured 

 the attention of the milk inspectors and those interested in 

 milk improvement. The picture presented by a sample of rela- 

 tively dirty milk was quite startling. However, as soon as this 

 was brought to the attention of the milk producers and hand- 

 lers, dirt practically disappeared from the milk. As a result the 

 usefulness of the sediment test as a means of further improving 

 the milk supply seemed at an end, and the sediment test has 

 been almost forgotten. 



Standards of Keeping Quality. 

 Both the public and the inspectors in their attempts at char- 

 acterizing good milk have been mindful of the length of time 

 that the milk would remain •sweet and otherwise unchanged; 

 that is, the keeping quality of the milk. It was early learned 

 that the sour taste can be detected in milk at about the time 

 it will titrate .3 per cent calculated as lactic acid. Accord- 

 ingly it has long been the practice to consider milk that will 

 titrate .2 per cent as beginning to be of doubtful keeping 



