JERSEY CATTLE BREEDERS. 371 



nearly all of the common butter adulterants By reason of this difference the 

 qnanlities of alkali necessary for saponification are different for equal weights of 

 batter fate and those of lard, tallow, etc. This difference is strikingly illustrated 

 in the table of analyses, and is the most reliable evidence of the purity or impurity 

 of the samples under consideration. The manipulation of the analyses being an 

 easy one, the determinations of the saturation equivalent is generally the first test 

 in determining the genuineness of the butter. If this number should fall under 

 250 it would be safe to call the sample genuine butter. 



SOLrBLE ACIDS. 



6. Pure butters have a large percentage of acids soluble in water. The per- 

 centage of these acids to the total weight of dried butter fat is about five. In the 

 analyses given, this percentage does not fall below 4.49, nor rise above 6, except in 

 one case of Jersey butter, made under exceptional conditions. In the butter sub- 

 stitutes these acids rarely go above 5 per cent. Their determination, therefore, is 

 an almost certain one of the purity of the sample. 



OPTICAL PROPERTIES. 



7. Pure unmelted butter, when viewed through a selenite plate by polarized 

 Hght, presents a uniform tint over the whole field of vision. 



On the other hand, butter substitutes give a field of vision of a mottled appear- 

 ance. This phenomenon is so marked that, with a little experience, the observer 

 will be able to tell a genuine from an artificial butter, with a fair degree of accu- 

 lacy. While the examination should never stop with this optical test above, it can 

 bo advantageously used as a preliminary step. 



JERSEY BUTTER. 



By consulting the table of analyses, it will be seen that two samples of Jersey 

 bntter were examined. Both of these were from the celebrated cow Value 2d, 

 oirned by Watts & Seth, Baltimore, Md. 



In the first sample analyzed, viz: No. 1,708 the percentage of soluble acids rises 

 to the high figure of 6.79. This is by far greater than in any other butters sub- 

 jected to examination. This samjjle was secured from the 25 pounds produced in 

 one week while under test. 



In No. 1,712, we have a sample of butter taken from the same cow immediately 

 after the test' had been made, and when, it is fair to presume, her system was some- 

 what deranged by the severe trial to which it had been stibjected. In this sample 

 the percentage of soluble acids was only 4.52. 



In both cases the melting point of the butter fat is remarkably high, and I am 

 told that Jersey butter will keep its form in hot weather better than any other 

 Tariety. This point, however, could only be determined by examining a much 

 larger number of samples. 



