No. 8. 



DEPARTMENT OF AGRICULTURE. 



Ml 



the Association of German Agricultural Experiment Stations has 

 been making special studies of cattle foods and has assigned to 

 various members the duty of preparing quite complete monographs, 

 describing the composition, manufacture and feeding properties of 

 the several important feeds. While these monographs are based 

 chiefly upon the foods found in the European market, so that they 

 do not precisely represent the corresponding American products, the 

 general nature of the materials on both Continents is so similar that 

 I have felt that it might be of interest to present an abstract of the 

 monographs on the subject of brewers' and distillers' grains pre- 

 pared by Professor Dietrich, of Marburg. 



Brewers' grains are derived directly from malt and, more re- 

 motely, from barley, so that the latter grain may be regarded as 

 the original raw material of brewers' grains. 



Barley, as offered on the market, is composed essentially of three 

 parts: (a) The hull, fruit and seed coats; (b) the embryo; and (c) the 

 endosperm or starchy part. The hull of the barley, which is of es- 

 pecial importance because of its abundance in brewers' grains, is 

 composed of a material like straw, yevy rich in silica. Omitting the 

 author's description of the anatomy of the grain and the qualities 

 it should possess for brewing purposes, w^e pass to its composition. 

 Maercker found that in the European barleys the hulls amounted 

 to five per cent, in the thin hull varieties; seven and one-half per 

 cent, in those of middle thickness; and over ten per cent, in the 

 thick hulled kinds. Richardson, examining thirteen American bar- 

 leys, found the percentage of hull to range from 12.5 to 16.9 per 

 cent.; average, 15.2 per cent. The average composition of barleys 

 of different grades and of European origin is stated by Maercker 

 as follows: 



This statement does not include mention of the fat and ash which 

 amount, on the average, to 2.3 and 2.7 per cent, respectively. The 

 glassy barleys, which are of lower brewing value than the mealy 

 varieties, contain somewhat more protein. 



Respecting the nitrogenous substances of barley grains, 97.5 per 



