132 



MAINE STATE COLLEGE 



In studying these figures we discover that these two sets of 

 results are inconsistent. 



The fat in tlie whole milk diminished by the amount in the 

 skimmed milk and butter milk should be the same as that of the 

 cream less the fat in the butter milk. This does not seem to be 

 the case, however, neither does there appear to be any error in 

 the data. We are not now able to explain this discrepancy. The 

 possible causes are an actual loss of fat, errors of weighing, and 

 errors of chemical analysis. It is already ascertained that the 

 second named cause could not have existed, certainly not to pro- 

 duce an error so large, so uniform and always on the same side. 

 By using the figures of a previous table we learn that the solids of 

 the sour cream added to the solids of the skimmed milk, also fall 

 short of equaling the solids of the whole milk. The difference can 

 be seen below : 







(U 













ci 













'^ 



a 















'C 











t> 



.s 











< 



hJ 









V 



>> 



a 



to 









o 



<s 



« 









c 



a 



a 



e4 





ei 



a 



a 



6D 





i-s 



^; 



Of 



< 



M 





lbs. 



lbs- 



lbs. 



lbs. 



lbs. 





1227.7 



751.1 



89i.6 



1015.2 



638.4 



Solids in sour cream and skimmed milk 



1183.7 



730.7 



862.1 



972.9 



594 1 





44 



20.4 



31.5 



42 3 



44 3 



Discrepancy in fats 



32.5 



20.5 



27.9 



46. 



39.7 



There is a similarity in these two sets of figures that is signi- 

 ficant. It is very evident that this apparent loss of solids 

 falls almost entirely upon the fat. Is it an actual loss of fat? 

 An investigation having as an object a defiaite answer to this 

 question is already planned. It is possible that it will receive 

 a negative reply, but it is difficult to understand what can be the 

 nature of the error, if one has o:'Curred. Whatever it may be, 

 whether of analytical work or not, it is worth while to find it. 



It is a fact that the amount of fat found in the sour cream 

 stands in about the right relation to the weight of butter, i. e., as 

 79 to 100. Fresh, unsalted butter will average less rather than 

 over eighty per cent of fat. This makes it appear that the weight 

 of fat in the whole milk diminished by the amount of fat in the 

 skimmed milk and butter milk is too large for the butter produced, 

 the ratio being 91 to 100. This fact goes to thow that tiie 

 descrepancy is not due to errors in the laboratory. 



