10 



BULLETIN 9U, U. S. DEPARTMENT OF AGRICULTURE. 



those from raw milk showing coagulation with alcohol slightly be- 

 low this point. Samples not showing close to this schedule are not 

 included in the discussion of results. 



The samples of evaporated milk put up in baby-size cans were run 

 in a Berlin pilot sterilizer used by the plant in determining the 

 amount of heat the different runs would stand. 



The results of this work did not agree closely with those obtained 

 at Grove City. All the samples of raw milk showing coagulation 

 with alcohol gave an evaporated milk that showed curdiness after 

 sterilization at a temperature of 112.8° C. (235° F.) for 30 minutes. 

 As the samples of raw milk, showing no coagulation with alcohol, 

 gave evaporated milks that in the majority of cases also showed 

 curdiness, no real comparison could be made as to the relative merit 

 of the alcohol and acid tests. 



Table 3 shows the result of the work done at Factory A on indi- 

 vidual patrons' milk samples. Of the 22 samples of raw milk show- 

 ing no reaction with alcohol, 14, after evaporating, showed curdiness 

 at the standard sterilizing temperature used, which happened to be 

 about what was found necessary to insure a safe-keeping milk, while 

 8 showed no curdiness. Of the 12 samples of raw milk showing 

 coagulation with alcohol, all showed curdiness after they were evapo- 

 rated and subjected to the standard sterilizing temperatures. 



Table 3. — Relation of alcohol, test and titratable acidity in Factory A. Evapo- 

 rated milk having close to 18.15 per cent solids not fat. Effect of sterilization 

 noted after shaking for 1 minute. 



Acidity. 



Raw milk not coagulating 

 with 75 per cent alcohol. 



Raw milk coagulating 

 with 75 per cent alcohol. 



Total 

 samples. 



Effect of 

 sterilization. 



Total 

 samples. 



Effect of 

 sterilization. 



Curdy. 



Not 

 curdy. 



Curdy. 



Not 

 curdy. 



Per cent. 

 0.11 to 0.12... 









1 

 

 3 

 3 



4 

 

 1 

 



1 





 3 

 3 



4 

 



1 

 





 

 

 

 

 

 

 



.12 to .13... 

 .13 to .14... 

 .14 to .15... 

 .16 to .16... 

 .16 to .17... 

 .17 to .18... 

 .18 to .19... 



4 

 3 

 4 

 3 

 5 

 3 



2 



2 

 2 

 3 

 4 

 1 



2 

 1 

 o 

 

 1 

 2 



Total 









22 



\A 



8 



12 



12 







The alcohol test was further tried out on a commercial basis in 

 this plant. The individual cans of milk received at the intake 

 were tested with alcohol according to the method already described. 

 All the milk showing no coagulation with alcohol was run in a sepa- 

 rate vat and condensed in the large factory pan as a separate batch. 



