56 STUDIES OF AMERICAN BARLEYS A XI) MALTS. 



48 per cent of potash, 2 per cent of lime, and IT per cent of magnesia. 

 This explains why the loss of ash is greater than that of phosphoric 

 acid. According to Konig, barley bran contains about 7 per cent 

 of ash, of which 50 per cent is phosphoric acid. That fact explains 

 why such a loss in bran takes place during the process of malting 

 barley. A large portion of the ash lost, consisting of phosphoric 

 acid and other salts, would naturally come from the bran, which con- 

 stituent of barley is richest both in ash and in phosphoric acid. The 

 protein lost during malting is, of course, to be found chiefly hi 

 the malt sprouts. In order to be thus transported from the barley 

 grain to the malt sprout, the insoluble protein had to be made soluble 

 by the proteolytic enzymes which are always present in grains and 

 only await propitious conditions in order to become active. The in- 

 soluble protein, having been converted into soluble and movable 

 protein, and possibly also having been changed into the amid form, 

 migrates to the growing plantlet and rootlet and again becomes 

 insoluble and fixed, just as the starch first becomes soluble before it 

 can migrate, and through physiological processes again becomes 

 insoluble in forming cellulose for the cell walls, etc. It should be 

 noted that high-protein barleys lost on an average over 16 per cent 

 of the total nitrogen, while the low-protein barleys lost about 11 per 

 cent on malting, the former losing considerably more starch also 

 during this procv . 



Analysis of the sprouts or rootlets obtained from malted barley 

 showed that they contained about 5 per cent of the total phosphoric 

 acid, 20 per cent of the potash, and from 2 to 3 per cent of the lime 

 and magnesia found in the malt. The difference between the total 

 loss observed in malting and the above figures shows the amount of 

 these constituents actually lost on steeping. 



Brown and Morris b show that in malting there is an increase of over 

 300 per cent of cane sugar in the embryo and a still larger increase in 

 the endosperm, besides which a large amount of maltose is found in 

 the malt endosperm, having been produced from the starch of the 

 barley endosperm. Similar results were obtained by O'Sullivan c long 

 before in his masterly researches on sugars. Delbriick d quotes Griis> 

 and Schonfeld's work showing that despite the fact that enzyms are 

 breaking down the starch into sugar during malting, a considerable 

 reconversion of starch from the sugar takes place, especially during 

 the drying of the malt. Hoffmann and others (see Delbriick) showed 

 that the drying of malt likewise changed amids into protein. This 

 has led to a comparison of the physiological process taking place 



a Untersuchimg landwirtschaftlich und gewerblicli wiclitiger Stoffe, p. 771. 

 6 Text-book of Science <f Brewing, p. 74. 

 C J. Chem. Soc., 1886, 41): r,s. 

 <*J. lust. Brew., 1906, 12: 044. 



