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the apparently spontaneous precipitation of this tannin in order to 

 show that it can be produced in wine without any albuminoid being 

 necessarily present, and without requiring the formation of an 

 insoluble compound with another substance. He adds that it 

 appears to him impossible to consider these turbidities as due ex- 

 clusively to combinations of tannin with albuminoids, either derived 

 naturally or added with the finings. 



We are inclined to the opinion that the tannic acid of hops plays 

 a most insignificant part in the brewing of beer. We do not say 

 that it plays no part, but whatever happens to it its power for good 

 or evil is negligible. 



On the other hand, looking at tannic acid from the point of view 

 of its relationship to the hop, although we know but little we are on 

 safer ground. For it may be considered more scientific to try first 

 and ascertain what part may be assigned to the tannic acid in the 

 hop plant, before hastening to the conclusion that as it is present in 

 hops it is therefore necessary in beer. 



There is a general consensus of opinion among scientific experts 

 that a high percentage of tannic acid denotes a good hop, but the 

 figures obtained (and there are plenty of them) do not bear it out 

 when the hop is valued commercially. We are inclined to agree 

 with the opinion rather than the figures, for two reasons: first, 

 because hops are seldom valued according to their real actual worth 

 to the brewer as measured by their chief constituents, and secondly, 

 because the various methods of estimating the tannic acid of hops leave 

 a good deal to be desired on the score of accuracy. With respect 

 to the first point, hops are valued nearly exclusively by the " nose " 

 and the " rub," especially the former. We do not dispute the great 

 importance of the " nose," as it certainly gives an indication of the 

 final flavour of the beer in which the hops are used, in so far as the 

 hops influence that flavour ; the " rub," too, is a qualitative test of 

 the richness of the hop in resin. But to neither of these tests can 

 any figure denoting measurement be applied, and they are so 

 subject to the personal equation of the person testing that their 

 value as tests is uncertain and indefinite. 



