12 BULLETIN 576, U. S. DEPARTMENT OF AGRICULTURE. 
It is difficult\to give any definite directions as to the temperature 
to be used when a mixture of skim milk and buttermilk is handled, 
as it is impossible to tell with any degree of accuracy how the curd 
will act during the process of manufacture. Buttermilk from cream 
ripened to a high acidity works much differently from that of cream 
ripened to a low degree of acidity, and because of the direct influence 
of the condition of the buttermilk a variation in the range of tem- 
perature is necessary. A much higher temperature for heating the 
coagulum can be used with a mixture containing a good. proportion 
of buttermilk with less danger of injury to the quality of the cheese. 
A temperature of 90° to 115° F. produces the desired results with a 
mixture containing as high as 50 per cent of buttermilk, although 
it rarely is necessary to exceed 105° F. Additional time is required 
for draining the curd from a mixture containing a large proportion 
of buttermilk. 
In salting the curd from a mixture of buttermilk and skim milk 
care must be taken to prevent a mottled effect on the color of the 
finished cheese. The curd from the skim milk is perfectly white 
compared to .. creamy color of that from the buttermilk, owing to 
the butter color added to the cream. The color of the buttermilk 
curd gives a richer looking product, provided it is well blended 
throughout the cheese to prevent an unevenness of color. 
The yield of cheese from a mixture of skim milk and buttermilk in 
the proportions indicated compares favorably with that made from 
straight skim milk, and is likewise affected by the same influencing 
factors largely under control of the maker. 
The advisability of using a mixture containing much more than 50 
per cent of buttermilk is doubtful. Experience indicates that the 
use of about 50 per cent of skim milk is necessary in order to insure 
the highest quality of cheese. The use of more than 50 per cent of 
buttermilk lessens the quality of the product, which can not be sold 
as the best grade of cottage cheese. 
MAKING BUTTERMILK CHEESE. 
Creameries having only buttermilk of good quality can make it 
into a fair grade of buttermilk cheese by using the vat method or the 
ejector method of heating the soured buttermilk to precipitate the 
curd. 
Because of the fineness of the curd in heating the buttermilk, ex- 
treme care must be taken to prevent breaking it up still finer. The 
‘amount of stirring required to bring the temperature of a vat full 
of buttermilk up to the proper point has a tendency to break up the 
curd so that a portion of it is liable to be lost during the process of 
draining. The method of running the soured buttermilk through the 
ejector heats the buttermilk to the required temperature with the 
least possible breaking up of the curd. With that method the curd 
