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10 Ibs. per quarter, the other left unhopped. The following results 

 were obtained calculated on the dry wort solids : 



Total soluble albuminoids in wort ... ... 6-010 per cent. 



after boiling ... 5-800 



with hops 5-672 



That is to say, of the total albuminoids present an apparent 

 increase of only 2-13 per cent. ' I2 ?} was precipitated 



by the addition of hops ; and it does not follow that this 

 was due to tannin, as there is another body known as 

 phlobaphen, which is present in hops and is somewhat readily 

 formed from tannin, and this body will likewise precipitate 

 albuminoids. In connection with this subject another experiment 

 of BRIANT and MEACHAM (Institute of Brewing, Vol. VI, p. 160), 

 is interesting. In it they estimate the total albuminoids in two 

 brewery worts before and after boiling (a) with 8 Ibs. of hops per 

 quarter, and (b) with 16 Ibs. of hops per quarter. The amount pre- 

 cipitated in each case was practically the same namely (a), just at 

 boiling 5-93 per cent, of soluble albuminoids, and after boiling 575 

 per cent., making a difference of 0*18 per cent., or 3*035 per cent, of 

 the total albuminoid. In the case of (b) the total albuminoid just at 

 boiling was 6*01 per cent., and after boiling 5-83, making again a 

 difference of o % i8 or 2-995 per cent, on the total albuminoid present. 

 The differences here are within experimental error, especially con- 

 sidering the practical difficulties under which the samples had to be 

 taken in the brewery. As the first samples were taken just as the 

 wort started boiling, it might be objected that some precipitation had 

 taken place, but in answer to this it must be pointed out that tannin 

 is not readily removed from hops, the authors saying that they have 

 always found a considerable amount of tannin in the spent hops 

 after one boiling in the copper. However, the experiments quoted 

 are sufficient to prove that the value of tannin as an albuminoid 

 precipitant is negligible, and this view is amply corroborated by 

 the work of HYDE, AUBRY, HERON, and others. 



A later aspect of tha tannin of hops is that it combines with 

 certain albuminoid bodies of a peptone nature, and is therefore 



