ILLINOIS STATE DAIRYMEN'S ASSOCIATION. 157 



weight of tlie butter fat brought to the creamery and the but- 

 ter sold from the creamery from the milk. 



Mr. Judd : Does it run somewhere near an even amount — 

 about fifteen per cent. ? 



Prof. Farrington : In careful work, yes ; but there is from 

 twelve to perhaps sixteen per cent, more butter than there is 

 butter fat; that is, when the separators skim their milk clean 

 and there is not much fat left in the skim milk, and when the 

 cream is so ripened and churned that there is very little fat 

 left in the buttermilk, then the amount of water and salt in the 

 butter is about sixteen per cent, more than the amount of the 

 butter fat that you start with. 



Mr. Carlson : Taking the milk every other day in the win- 

 ter time the cream is more or less clotted, and in many in- 

 stances you will find chunks of cream lying in the bottom of 

 the weigh-can after the milk has run out. I have found that 

 in the winter time generally, my yield of butter above my oil 

 test is much greater than in the summer time when I get a 

 better sample of the farmer's milk. I have had my yields go 

 as high as twenty-nine per cent, when at other times it will 

 not go below ten when I was getting a fair sample. Last year 

 my average was between eleven and twelve per cent, increase 

 in my butter yield above my oil test. 



Prof. Farrington : I think that an overrun of twenty-nine 

 per cent, or even twenty per cent, is a strong indication of an 

 inaccurate test of the milk, either that the sample could not be 

 properly taken because of some difficulty ,or the test was not 

 made accurately. Perhaps the speed of the tester was not 

 high enough. 



Mr. Carlson: The richer the milk in butter fats, doesn't 

 it overrun the more? 



Prof. Farrington: Of course, where you have a very rich 

 milk the amount that is lost in the skim milk is a smaller per- 

 centage of that rich milk, than it would be of thin milk. I 

 don't know why the percentage of overrun should be more. 

 If milk comes into the factory that tests only two per cent, of 

 fat and the separator leaves two-tenths of one per cent, of fat 

 in the skim milk, of course, that two-tenths of one per cent, is 

 a larger proportion of the two per cent, than if the milk 



