94 



present in the finished beer as a " tanno-peptone." In reference to 

 this HAYDUCK and GOLDINER published some results in the Wochen- 

 schrift fur Brauerei in 1894 (^ P* 49) The authors separated 

 some tannin from hops and found that it precipitated albumin 

 incompletely ; elsewhere they state that it is soluble in boiling 

 water, but almost insoluble in cold water, that some of this albumin 

 tannin is still left in the clear and cooled wort, but that more comes 

 out during fermentation, and only a trace remains in the finished 

 beer ; but the analyses they give show as much as "024 per cent, in 

 English ale, Munich and Berlin beer showing half as much. Now 

 024 per cent, is really a large quantity ; taking a pale ale of 23 Ibs. 

 gravity, hopped at the rate of 10 Ibs. per quarter, and dry-hopped 

 with a pound per barrel, the hops containing 3 per cent, of tannin, 

 and the malt giving 92 extract, then 90 per cent, of the tannin 

 would have to go into the finished beer to give -024 per cent., and 

 it is extremely doubtful if the whole of the tannin of the dry hops 

 would be dissolved out of them. At this rate there would be no 

 appreciable precipitation on the coolers. German beers are 

 hopped far less than English beers, so that "012 would be a high 

 figure for the tannin in them also. But we can hardly consider it 

 proved that the tannin is in chemical combination with the albumi- 

 noid matter, and MATHIEU'S work referred to further on is highly 

 suggestive. 



The authors go on to say how the influence of hop tannin is 

 shown in the much smaller quantity of soluble albumin present in 

 strongly hopped English ale than in the much less hopped German 

 beers. But here again no account is taken of the great differences 

 in the processes of brewing English beer and German beer, 

 especially in regard to the possible action of proteolytic enzymes in 

 the decoction process ; there are considerable differences also in the 

 English and German malting processes, the latter being what 

 we term highly forced, which would influence the amount and 

 constitution of the nitrogenous bodies. 



HERON (Fed. Inst. of Brew., 1896, p. 161) takes the " tanno- 

 peptone " view, and states (p. 177) " there is strong proof that 

 tannin unites and forms a definite compound with certain nitro- 

 :\ 



