II 



BUTTER 



175 



which varied considerably from the figures given as standards 

 for normal butter. Thus the lower limit for the Reichert- 

 Meissl number of natural butter had gradually to be reduced 

 from 28 to 24, and finally to 19. In the same way, the iodine 

 number was put at 38 for the maximum, but it is now known 

 that it sometimes rises to 50. With regard to the refractive 

 index, it has previously been mentioned (p. 159) that the 

 figures given by Wollny are altogether too low, for he states 

 that 44*2 divisions at 40 C. is the highest number to be allowed 

 for pure butter, whereas it has been found that 47 divisions 

 may be got with pure butter. 



It will thus be seen that sometimes the chemist has almost 

 insuperable difficulties to overcome if he wishes to prove in 

 some particular case whether or not butter has been adulte- 

 rated. The best safeguards against adulteration are, and will 

 continue to be, legal standards and a strict control in the 

 preparation and sale of the so-called artificial butters. 



Synopsis of the Most Important Analytical Data for Butter, 

 Margarine and Cocoa-nut Fat. 



II. MIXING OF WATER WITH BUTTER. 



Butter churned and prepared in the usual way contains 

 11-15 per cent, water, but the percentage can easily be raised 

 by special methods, and may even reach 30 per cent, without 

 the appearance arousing suspicion. The object, of course, of 

 incorporating such large quantities of water is to increase the 

 weight of the butter, so the practice must be regarded as a 



