48 UNIVERSITY OF WISCONSIN STUDIES 



969.59 calories or an increase of approximately 105 calories 

 with each increase of 1 per cent fat. The use of the calo- 

 rimeter, however, is too technical even for inspection work. 

 From the above data it is evident that the use by the house- 

 keeper of the fat content as an index of food value is correct 

 in principle though the method of estimation is necessarily 

 crude. The Babcock test for fat determination is both simple 

 and accurate with the added advantage that the test itself 

 is well understood and the necessary apparatus is ordinarily 

 at hand. Accordingly, the fat content is in all particulars 

 well adapted to serve as an index of food value of milk as it 

 is delivered to the consumer. 



The safety of the milk as delivered may be about equally 

 well guaranteed in either of two ways ; by frequent inspection 

 of the health of the cows and people concerned in its pro- 

 duction and handling, or by proper pasteurization and pro- 

 tection from reinfection. Safeguarding the milk by means 

 of health inspection of cattle and men adds from 3 to 5 cents 

 per quart to the cost of the milk while the expense of pasteur- 

 ization varies from about 1 cent per quart in small quantities 

 to about % cent per quart in large quantities. Under such 

 conditions it is not strange that practically all the actual 

 advance in safeguarding municipal milk supplies has been 

 made through the adoption of pasteurization. Where pasteur- 

 ization is relied upon to make milk safe from germs of in- 

 fectious diseases, there should be a requirement of tempera- 

 ture recording devices in connection with the process and a 

 frequent inspection to ascertain that the apparatus is in 

 proper working condition and that the milk is properly pro- 

 tected after pasteurization. 



The housewife is aware that when a bottle of milk is un- 

 disturbed for some time the dirt in the milk settles to the 

 bottom and she accordingly looks at the bottom of the bottle 

 to determine the cleanliness of the milk. In inspection work 

 the amount of insoluble dirt in milk as delivered to the con- 

 sumer may be estimated . very accurately by means of the 

 sediment test. 



