Conditions Affecting Butter-Fat. 457 



amount of milk-fat is conflicting, but the weight of the evidence 

 goes to show that, although in certain cases fat may have an 

 indirect beneficial effect, nevertheless, in the case of a normally 

 fed animal, it has no contributory action on the amounts of the 

 glycerides secreted. 



Baumert and Fa!ke have, however, stated that not only is 

 butter-fat greatly changed in character through feeding with 

 various fats, but the alteration is always characteristic of the 

 fats used — that is, the butter-fats produced by feeding cows 

 with sesame, cocoa-nut or almond oil exhibit on analysis the 

 same characteristics as are found in artificial mixtures of butter- 

 fat with these three oils. 



According to Bartlet, gluten food containing much oil 

 produces soft butter, yet when free from fat the gluten will not 

 have the hardening effect of cotton-seed meal; soft butter 

 cannot be attributed to an excess of fat or to a deficiency of 

 nitrogenous food. 



Hills tried the effect of adding various oils to food and found 

 that with cotton-seed oil the butter was hard and of good 

 quality ; linseed meal rendered it soft and sticky, whereas maize 

 oil made it soft and oily. 



In this connection mention may be made of the results of 

 certain feeeding experiments made at the Wye Agricultural 

 College, at the instance of the Board of Agriculture, which are 

 of importance in relation to the search for certain vegetable oils 

 in butter, as indicative of the presence of oleo-margarine. The 

 samples of butter produced by the cows so fed were tested 

 at the Government Laboratory. It was found that : — 



1. Cows fed on cotton-seed cake give a butter which shows a reaction for cotton- 

 seed oil. 



2. The above is true even when only a small quantity is given, and increases with 

 continuous feeding up to a certain limit which cannot be passed, 



3. The reacting substance passes into the milk within 24 hours, and continues 

 several days after the food is stopped. 



4. The intensity of the reactions varies with different cows, but does not in any 

 case indicate a greater amount than 1 per cent, of cotton-seed oil in the butter. 



5. Feeding on cotton-seed cake gives a butter which, on analysis, shows results 

 tending to diverge still more widely than usual from those yielded by margarine, thus 

 making it easier to distinguish between this and a mixture of margarine and cotton 

 seed oil. 



6. Feeding with sesame cake gives no reaction for sesame oil in the butter, even 

 after it has been continued for two months. 



