BUTTER 85 



mination of the volatile acid, but some other 

 confirmatory processes are occasionally employed. 



Qualitative Tests. — Two tests are convenient 

 for preliminary examinations, especially for sort- 

 ing out, when many samples are to be tested. 

 The experience of Dr. William Beam and myself 

 in testing many hundred samples for the Dairy 

 and Food Commissioner of Pennsylvania showed 

 that the methods are satisfactory and useful. 



Heating test. — When butter is heated in a 

 small tin dish directly over a gas flame, it melts 

 quietly, foams, and may run over the dish. 

 Oleomargarin, under the same conditions, sput- 

 ters noisily as soon as heated and foams but little. 

 Even mixtures of butter and other fats show this 

 sputtering action to a considerable extent. The 

 test is not applicable to butter which has been 

 melted and reworked (renovated or process 

 butter). 



Saponification test. — An alcoholic solution of 

 sodium hydroxid, boiled up with butter, and then 

 emptied into cold water, gives a distinct odor of 

 pineapples, while oleomargarin gives only the 

 alcoholic odor. 



Quantitative Methods. Volatile Acids. — 

 This method, suggested by Hehner & Angell, 

 systematized by Reichert, is generally called the 

 Reichert process. In this form it is carried 

 out by saponifying 2.5 grams of the fat, adding 



