280 PRINCIPLES AND PRACTICE OF MILK HYGIENE 
the size of the curd. P., increased amount of fluid, less 
curd. Ps;, amount of fluid large in proportion to the size 
of the curd. This type of curd is produced when a large 
proportion of peptonizing bacteria are present in the 
milk. When the number of bacteria is large, it is usually 
an indication that the milk has been contaminated with 
dust from hay, fodder or soil, or that a suppurative con- 
dition is present in the herd. When milk is produced 
under good conditions and is kept cool, the peptonizing 
bacteria (udder cocci) will predominate but the total 
number of bacteria will be small. 
3. Gaseous Curd.—A white, jelly-like curd contain- 
ing gas bubbles and, when gas has been formed in large 
quantity, presenting a sponge-like appearance. More 
or less fluid is present and this may also contain gas bub- 
bles. G:, a few gas bubbles in the cream layer or in the 
curd. Ge, gas bubbles numerous in the cream and curd; 
gas bubbles may also be present in the fluid. Gs, curd 
sponge-like, containing many gas bubbles; may be split 
and a portion driven to the top; gas bubbles in fluid. 
The gaseous curd is produced when a large percentage 
of gas-forming bacteria is present and is usually an in- 
dication that the milk has been contaminated with an ex- 
cessive amount of manure. It may also occur when pol- 
luted water is used to wash the milk vessels and utensils. 
4. “Flaky” or Flocculent Curd.—Curd in flakes or 
flocculi, associated with a turbid fluid, which may be 
whitish, yellowish, or otherwise discolored. F., curd in 
fine flakes or partially homogeneous. Fl, large flakes 
and considerable fluid. F;, large flakes, torn, with white 
or discolored fluid. This type of curd is produced when 
saccharomyces which ferment lactose are present in large 
numbers. The casein is permeated with fine gas bubbles 
