A Practical Treatise on Brewing/Ropiness

by William Black

ROPINESS.

Ale and beer are sometimes liable, when long kept, to become thick and viscid, pouring out like oil. This defect is called ropiness. Beers, when long stored in the cask in a fined state, are liable to undergo this change, owing to the small portion of gelatine left in the beer. It is, therefore, more advisable to store beer in the rough or unfined state. Ropiness in this case proceeds from deficiency of tannin, and superabundance of gluten. Hops will supply tannin and thus effect a cure. Catechu, which is almost all fine tannin, might also be used; but hops are to be preferred. Ropiness is often produced by the injudicious mixture of old and new beer.