54 Facrory SANITATION 
heads.” Patrons sending such milk should be looked alter at 
once. 
If the curd dissolves, or no curd is formed and the milk 
changes into a transparent liquid, it usually is contaminated by 
germs from the dust of hay and bedding, or polluted water. To 
this class of organisms belone Bacillus subtilis, Bacillus fluores- 
cens liquifaciens, Plectridium foetidum, Bacillus putrificus, ete. 
Some of these are violent gas producers and most of them are 
spore-bearers. ‘They are the cause of the most disastrous milk 
defects. Dairies from which such milk comes should be vigor- 
ously inspected and all milk from them should be rejected, until 
the patrons have learned how to furnish sanitary milk. 
Milk that remains unchanged for twenty-four hours when 
subjected to the fermentation test, suggests that it contains some 
preservative. It is possible, however, for milk produced under 
ideally sanitary conditions to remain normal and unchanged even 
at these high temperatures for several] days. \WWhere milk comes 
to the factory in bulk as is the case in the condensery, samples 
showing abnormal keeping quality should be regarded with sus- 
picion, and the respective dairies should receive immediate and 
thorough inspection. 
Tests for Butterfat and Specific Gravity.—In the factories 
where the milk is not paid for on the butterfat basis, composite 
samples should be taken daily, to be tested for fat and specific 
gravity, at regular intervals of from two to four weeks, in order 
to detect possible adulterations by skimming or by the addition 
of water. For specific directions for the Babcock test, the use of 
the lactometer and tests for preservatives see Chapter XXX 
“Chemical Tests and Analyses of Milk and Milk Products.” 
FACTORY SANITATION. 
In the previous paragraphs, special emphasis was placed on 
the great importance of a good quality of fresh milk. Tt is equally 
essential that the factory be kept in exemplary condition as to 
cleanliness and sanitation. ‘Uhis is necessary because of its effect 
on the ‘patrons and on the wholesomeness and marketable prop- 
erty of the fimished product. 
Effect on Patrons.—It does not take the watchful eye of the 
intelligent patron, who daily comes to the factory, very long to 
