DAIRY FARMING DAIRYING. 277 



second period of 28 days, 2.8 lbs. of the gralu ration was replaced by 2..3 lbs. of 

 soy beau meal minus the oil, and in the third period, lasting 21 days, 0.6 lb. of 

 the normal grain ration was replaced by the same amount of soy bean oil. In 

 the second period the second lot consumed about ^ lb. more digestible protein 

 than lot 1, and in the third period 0.6 lb. more fat. One cow lost in live weight 

 owing to digestive disturbances in the second period, but the flow of milk 

 appeared normal except in the case of one cow in lot 2 near the close of the 

 third period. Methods for determining the chemical composition of the milk 

 fat are given. 



In the first period lot 1 yieldetl a fat with a little higher saponification value 

 than lot 2. Other minor difCerences were also noted. In the second period 

 careful study of the analytical data failed to reveal auy marked differences that 

 could be attributed to the change in the ration. In the milk fat from lot 2 the 

 higher iodin number might indicate a small increase in the amount of unsatu- 

 rated acids beyond that resulting from the advance in the period of lactation. 

 If such were the case the increase in all probability should be attributed to the 

 influence of the oil rather than to the bean protein. In the third period when 

 the bean meal was replaced by the normal ration and the soy bean oil, the Kotts- 

 dorfer number in lot 2 fell from 2ol.r)0 to 221.65, and the Reichert-Meissl from 

 27.05 to 23.27. The iodin value increased from 81.90 to 40.25, giving additional 

 evidence of the increase of oleic and possibly of linoleic acids. In terms of oleic 

 acid, by calculation, this increase amounts to 9.26 points. In the first 2 periods 

 both herds showed quite similar acid numbers, varying from 0.32 to 0.38. In 

 the third period, in case of lot 1, the acid number increased slightly to 0.48, and 

 in lot 2 to 1.39. The ether number naturally varied with the saponification and 

 acid numbers, being lowest in the milk fat produced by lot 2 in the third period. 

 The percentage of glycerol in fat fell to 12.04 in the case of lot 2 in the third 

 feeding period. The total fatty acids were quite uniform except during the last 

 period for lot 2. The Yalenta test had a slightly lower turbidity point in lot 1 

 than in lot 2. In the second period this difference was more noticeable, and it 

 was very marked in the third period, amounting to nearly 12°. Other differences 

 were noted in the third period in the refractive index, insoluble fatty acids, the 

 saponification number of the insoluble acids, and the soluble fatty acids. Meth- 

 ods for determining these and other contents are given. 



The butter produced by lot 2 was much softer than that from lot 1. Samples 

 were scored by experts in Boston and New York, and some of them, particularly 

 those in lot 2 in the third period, were off flavor. Churning data and analyses 

 of feeds are given. 



The following conclusions were drawn : 



" Soy bean meal partially extracted (2.3 lbs. per day and head) seemed to be 

 without influence in changing the proportions of the several milk constituents or 

 in imparting any flavor to the milk. 



' Soy bean oil (0.6 lb. per day and head) was likewise without influence on the 

 composition and flavor of the milk. 



" Soy bean meal did not modify the chemical character of the butter fat, 

 neither did it have any effect upon the separation of the fat from the milk 

 serum, the time of ripening of the cream nor on the thoroughness of the churn- 

 ing. Expert butter scorers could not detect any particular flavor in the butter 

 as a result of feeding the meal. The meal impartefl a noticeable softness to the 

 body of the butter, but not sufficiently so as to injure its commercial value ex- 

 cepting during the warm months. The softness of the body of the butter was 

 due probably to the oil contained in the bean meal and not to the bean protein. 



"Soy bean oil depressed the volatile fatty acids ( Reichert-Meisel number) 

 and thus lowered the saponification number of the butter fat; it increased the 



