36 MANUFACTURE AND CURING OF CHEESE. 
It is understood by choose makers that milk develops so differently 
from day to day, or even for the same day in different vats, that it is' 
impossible to make an exact schedule of treatment which would apply 
to every lot of cheese made. Only one factor was constant, and that 
was the temperature of setting the milk, winch was always exactly 86° 
F. The rennet test of the milk was always made before setting, and the 
milk reached about a certain degree of ripeness depending upon the 
way it had been developing. The regular Marshall rennet test was 
used, but instead of timing it by degrees as is customary it was timed 
by a watch in minutes and seconds, which on the whole was much 
more exact and satisfactory. The table shows that the variation in 
the rennet test was from two minutes and forty-five seconds to four 
minutes and fifteen seconds. This wide range was not accidental, but 
was due to the fact that the milk was ripening at different rates at 
these different periods. The time from setting to cutting varied with 
the low-rennet cheese from thirty to forty minutes and with the high- 
rennet cheese from twenty-two to thirty minutes. The cheese was 
cut when the stage of coagulation adopted by most cheese makers was 
reached. It is impossible to describe this stage intelligibly, but it is 
well known to practical cheese makers. The temperature of cooking 
varied from 98° to 101° F. The vats in which the cheese was made 
had mechanical agitators, which required a little higher cooking than 
under the old method of stirring by hand and with rakes. The time 
for cutting, cooking, drying, and salting is calculated from the time 
of setting, so that under the headings for time of grinding and time of 
salting six hours and fifty-five minutes or five hours and thirty min- 
utes, as the case may be, means that that length of time had elapsed 
since the milk was set. The time for drawing the whey was regulated 
by the acid test after the first week, though as a check the iron test 
was made at the same time. The acid was allowed to develop about 
as high as was safe without causing an acid cheese. The time of 
grinding was regulated by the condition of the curd, and at this time 
also the acid and iron tests were made. Salting was likewise regu- 
lated by the condition of the curd. The other columns of the table 
devoted to firmness, flavor, and remarks will be taken up in discussing 
individual lots of cheese in connection with the scores. 
TREATMENT OF FACTORY-CURED CHEESE. 
The first part of the cheese kept in the factory curing room was held 
until it had about reached its prime condition, when it was put into 
the 32-degree room and held there until all the factory-cured cheese 
was ready for scoring. As heretofore stated, the factory curing was 
not considered an important feature of the experiment, though there 
were several points brought out in the development of flavors in this 
factory-cured cheese that were of great interest in connection with 
