286 HOPS. 



Hop alkaloids ^. — Hops are assumed to contain an alkaloid 

 to which their Iiarcotic action is ascribed, and Griessmayer 

 succeeded in isolating a body giving the general reactions 

 of alkaloids. This he termed lupulin ; but the examination 

 of fine hops is said to have furnished merely negative results. 



Williamson isolated a hop alkaloid which he named 

 hopeine,^ and which is said to resemble morphine in its effects 

 though not attended by the same after-phenomena. Prior 

 assumes the identity with morphine of an alleged hopeine 

 preparation examined by Ladenburg. B. H. Paul discovered 

 cocaine in English samples of hopeine, and Gresshoff found 

 in other samples of different origin a body which, though 

 furnishing the reactions of an alkaloid, could not be brought 

 to crystallise." 



Although at present it cannot be asserted with confidence 

 that hopeine is the active alkaloid in hops, scarcely anyone 

 will be incUned to doubt that hops, like coffee, tobacco, 

 etc., do contain a specific alkaloid. As, however, nothing 

 is definitely known concerning this body, neither can any^ 

 thing be said as to its importance in brewing. Probably, 

 like alcohol, its action in beer is to produce intoxication. 



Carbohydrates and other non-nitrogenous constituents *. — In 

 addition to the cellulose present in hops Griessmayer dis- 

 covered glucose. Brown and Morris also found sugar and 

 an enzyme resembling malt diastase ; and gum was detected 

 by Rautert and Wimmer. 



, Finally, it may be mentioned that Wagner isolated from 

 hops a yellow body which he named quercitrin ; and Etti 

 detected arable acid. 



^ Thausing, Theorie wid Praxis der Malzbereitung und Bier fabrication, 

 Leipzig, 1898. 



^E. Prior, Chemie und Physiologie des Maizes und des Bieres, Leipzig, 

 1896. 



nbid. *Ibid. 



