120 



REPOET OF THE COMMISSIONER OF AGRICULTURE. 



I made no attempt to separate tliese two acids, but estimated the 

 total acidity and then represented it in terms of botli acids. 



The direct titration of the lactic acid in the kumys was attended with 

 such difficulty that the attempt was abandoned. Whatever indicator 

 was employed, the change in color was so obscured that no sharp reac- 

 tion could be obtained. 



To obviate this trouble the kumys was mixed with an equal volume 

 of saturated solution of magnesium sulphate. After shaking the mixt- 

 ure it was poured through a linen filter. The first portions running 

 through were turbid. After refilling these the filtrate was quite clear. 



Better results were obtained by using with the kumys equal volumes 

 of alcohol. The filtrate from this mixture was uniformly bright. In 

 this filtrate the acid was estimated by titration with standard sodic- 

 hydrate solution, making the proper corrections for dilution, and using 

 phenolphthalein as indicator. I would recommend this alcoholic method 

 of clarification to all who may have occasion to determine acid in milk. 



Alcohol. — The alcohol was estimated by distilling 500 cubic centi- 

 meters kumys with 100 cubic centimeters water until the distillate 

 amounted to 500 cubic centimeters. This being still turbid was redis- 

 tilled with a small quantity of water. The final distillate of 500 cubic 

 centimeters was used for the estimation of the alcohol in the usual way, 

 viz, by taking its specific gravity and calculating the alcohol from tables. 



Milk sugar. — The milk sugar was estimated by the method I recom- 

 mended in a paper read at the Philadelphia meeting* of the American 

 Association for the Advancement of Science. 



Fat. — Twenty grams of the kumys were evaporated to dryness in a 

 schalchen, the whole rubbed to a fine powder and extracted with ether 

 in a continuous extractor. The process of extraction lasted six hours. 



Albuminoids. — The albuminoids were estimated by evaporating 5 

 grams of the material in a schalchen, rubbing to a fine powder with 

 soda-lime and burning with the same in the usual way. 



Water. — In a fiat platinum dish, partly filled with washed and dried 

 sand, 2 grams of material were weighed and dried to a constant weight 

 at 100° C. Following are the results of the analyses : 



It will be of interest to compare these results with those obtained 

 by other analysts, both with kumys from mare's milk and from other 



•American Cliemical Journal, vol. 6, No. 5. 



