474 



SCIENCE. 



[Vol. VII., No. 173 



But while the writer does not advocate legisla- 

 tive prohibition, he does most strongly believe in 

 the necessity for legislative regulation. The ob- 

 jects to be attained by such regulation are, first, 

 to insure that only clean and wholesome materials 

 are used in the manufacture, and that the process 

 is conducted in a careful and cleanly manner : 

 and, second, to compel the sale of the product 

 under its own name and on its own merits. When 

 this is done, all is done that the state can properly 

 do. 



Space forbids entering into any discussion of 

 the best methods of reaching these objects. Some 

 system of registration and inspection of factories 

 would evidently be necessary to accomplish the 

 first ; while the second might be attained by com- 

 pulsory branding of packages, use of a peculiar 

 style of package, requiring manufacturer and 

 jobber to keep a record of all packages sold, with 

 name of buyer, and numerous other devices. 

 Probably both these objects would be most readily 

 accomplished by putting the whole matter in the 

 hands of the Internal revenue bureau, while it 

 might fairly be taxed sufficiently to cover the cost 

 of inspection, etc. 



Finally, it is to be remembered that butterine is 

 but one of many forms of food-adulteration. The 

 most satisfactory treatment of the subject would 

 be the enactment of general laws, state or nation- 

 al, upon the subject of food-adulteration, and the 

 provision of an efficient power to enforce them. 



Methods of detection. — There is no simple test 

 by which the consumer may determine for himself 

 whether a sample of butter is genuine : the adul- 

 teration can be detected only by the expert chem- 

 ist or microscopist. Butter, as already noted, dif- 

 fers from all other animal and most vegetable fats, 

 in containing about six per cent of the glycerides 

 of certain soluble fatty acids. It is upon this 

 fact that all chemical methods for the detection 

 of butter-adulteration are based. The original 

 method, as proposed by Hehner, consisted in de- 

 termining the percentage of insoluble fatty acids. 

 In butter this averages about 87.5 per cent, while 

 in other animal fats it averages about 95 per cent. 

 Koettsdorfer determines the weight of pure potash 

 required to saponify one gram of the fat. Owing 

 to the lower molecular weight of the peculiar 

 acids of butter, more potash is required to saponify 

 this fat ; the range being 221 to 232 milligrams of 

 potash for butter, and 195 to 197 for other fats. 

 Reichert, after saponifying the fat and setting 

 free the fatty acids again by addition of sulphuric 

 acid, all the operations being conducted in a uni- 

 form manner, distils over a fixed volume of the 

 resulting liquid, and determines the amount of 

 potash required to neutralize it. The distillate 



from 1 gram of butter- fat requires 13.0 to 14.9 cubic 

 centimetres of a deci-normal potash solution ; that 

 from other fat, a fraction of 1 cubic centimetre. 



Of these methods, Hehner's is too tedious for 

 ordinary use ; Koettsdorfer's is very readily and 

 quickly applied, and in general gives unequivocal 

 testimony as to the genuineness of the sample ; 

 Reichert's requires somewhat more time and skill 

 than Koettsdorfer's, but still is a simple method, 

 and gives trustworthy results, and has advantages 

 in certain cases. 



The results obtained by either of these methods 

 may evidently serve as the basis of an approxi- 

 mate computation of the extent of the adultera- 

 tion. Owing to the somewhat variable composition 

 of butter, however, the approximation cannot be 

 a very close one, and slight adulterations would 

 pass undetected. It will not often be the case, 

 however, that butter is slightly adulterated ; so 

 that practically but little difficulty will arise from 

 this fact, so far as the detection of the falsification 

 is concerned. For a calculation of the extent of 

 the adulteration, Reichert's method has proved the 

 more satisfactory in my laboratory, Koettsdorfer's 

 giving usually decidedly too low results. 



Cornwall 1 has recently called attention to the 

 fact that cocoanut-oil is said to be used in the 

 manufacture of butterine. This oil, unlike most 

 others, contains a considerable proportion of solu- 

 ble fatty acids ; and mixtures of this fat with 

 oleo-oil or neutral may be made which behave ex- 

 actly like butter with Hehner's or Koettsdorfer's 

 tests. They may be distinguished, however, ac- 

 cording to Cornwall, by Reichert's method, the 

 soluble acids being much less volatile than those 

 of butter ; the distillate containing, consequently, 

 but little of them. 



Besides the chemical methods, the more im- 

 portant of which have been described, various 

 attempts have been made to devise optical tests, 

 but with indifferent success. Among others, Dr. 

 Thomas Taylor, microscopist of the U. S. depart- 

 ment of agriculture, has described a method which 

 has received such extensive notice as to merit a 

 lew words. He proceeds substantially as follows : 

 some butter is melted and 'boiled' for a short 

 time (that is. the water which it contains is boiled), 

 and then allowed to cool slowly. A small portion 

 of the solidified butter is mounted in a little olive- 

 oil on an object-glass, and under the microscope is 

 seen to consist of irregular globular masses con- 

 sisting of aggregations of fat - crystals. When 

 these are examined with polarized light in the 

 dark field, each shows a pretty well defined St. 

 Andrew's cross. Dr. Taylor's original claim was 

 that these globules, and particularly their ap- 

 1 Report of New Jersey state board of health. 



