CONTROL OF CITY MILK SUPPLY 233 
the sample kept at the higher temperature will be largely 
of the lactic kind and may be practically as wholesome 
as the sample containing only 5,000 bacteria per c. c. 
From the standpoint of safety, it is of far greater 
consequence to know the kind of bacteria present in milk 
' than to know the actual numbers. For example, a sam- 
ple of milk may be produced under the strictest hygienic 
conditions, but if not properly cooled may show ten mil- 
lion bacteria per c. c. On the other hand, another sample 
of milk may be produced from diseased cows under 
filthy condition, if thoroughly cooled immediately after 
milking may contain less than ten million bacteria per 
Ce C 
Where bacterial counts have their greatest value in 
determining the purity of the milk is when the number 
of bacteria does not exceed 20,000 per c. c. Only under 
cleanly conditions can milk be obtained containing less 
than 20,000 bacteria per c. c. when delivered to con- 
sumers. 
Composition of Milk and Cream. Standards for 
milk, cream and ice cream are now found in most states 
and in the larger cities of the country. These standards, 
in the case of milk, call for a minimum per cent of fat, 
solids not fat and total solids; in cream and ice cream, 
as a rule, only a minimum per cent of fat is considered. 
The total solids are obtained by adding the fat and 
solids not fat, and where there are standards for the 
latter two, no standard for total solids is needed. 
The minimum per cent of fat in milk called for by 
the standards varies from 2.5 to 3.7; for solids not fat 
the minimum varies from 8 to 9.5 per cent, while the 
minimum for total solids varies from 11 to 13 per cent. 
The minimum limit for fat in cream ranges from 15 to 
