609 
CLASS 2.— INSPECTED MILK. 
This term should be limited to clean raw milk from healthy cows, 
as determined by the tuberculin test and physical examination by a 
qualified veterinarian. The cows are to be fed, watered, housed, and 
milked under good conditions, but not necessarily equal to the condi- 
tions prescribed for class 1. All persons who come in contact with 
the milk must exercise scrupulous cleanliness and must not harbor 
the germs of typhoid fever, tuberculosis, diphtheria, or other infec- 
tions liable to be conveyed by the milk. This milk is to be delivered 
in sterilized containers and is to be kept at a temperature not exceed- 
ing 50° F. until it reaches the consumer. It should contain not more 
than 100,000 bacteria per cubic centimeter. 
CLASS 3.— PASTEURIZED MILK. 
Milk from dairies which do not comply with the requirements speci- 
fied for classes 1 and 2 should be pasteurized before being sold, and 
should be sold under the designation “ pasteurized milk.” Milk for 
pasteurization should be kept at all times at a temperature not ex- 
ceeding 60° F. while in transit from the dairy farm to the pasteuriz- 
ing plant, and milk after pasteurization should be placed in sterilized 
containers and delivered to the consumer at a temperature not exceed- 
ing 50° F. 
All milk of unknown origin should be placed in class 3 and sub- 
jected to clarification and pasteurization. No cow in any way unfit 
for the production of milk for use by man, as determined upon phys- 
ical examination by an authorized veterinarian, and no cow suffering 
from a communicable disease should be permitted to remain on any 
dairy farm on which milk of class 3 is produced, except that cows 
which upon physical examination do not show physical signs of tu- 
berculosis may be included in dairy herds supplying milk of this 
class. 
This milk is to be clarified and pasteurized at central pasteurizing 
plants, which should be under the personal supervision of an officer 
or officers of the health department. These pasteurizing plants may 
be provided either by private enterprise or by the municipality, and 
should be located within the city. 
By the term “ pasteurization ” as used herein is meant the heating 
of milk to a temperature of 150° F. or 65° C. for twenty minutes, or 
160° F. or 70° C. for ten minutes, as soon as practicable after milking, 
in inclosed vessels, preferably the final containers, and after such 
heating immediate cooling to a temperature not exceeding 50° F. or 
10° C. 
1414— Bull. 56—09 39 
