The art of brewing : practical and theoretical / by Frank Faulkner.

  • Faulkner, Frank.
Date:
1876
Catalogue details

Licence: Public Domain Mark

Credit: The art of brewing : practical and theoretical / by Frank Faulkner. Source: Wellcome Collection.

    132/226 (page 120)
    would no doubt tend to fine beer by sinking slowly through it in a cloud-like state, but such agents are not sufficient for a brewer’s purpose, and consequently we have adopted animal gelatine in the form of isinglass to induce artificial fining, where spontaneous clarification cannot be expected or cannot be waited for. This isinglass has to be brought into a convenient condition for use by causing it to assume a gelatinous state, by means of steeping it in some sort of acid, usually an organic one. I suppose that in most cases old beer or “returns” is employed, and in many instances, this apparently profitable practice is a fruitful source of early acidity in such beers as are retained in stock or on ullage for any considerable time. It is far better to employ such an agent as sulphurous acid, the advantages of which I have pointed out before, and thus obtain finings, which practically are non-acid, while the liquid portion acts as a preservative agent in your beers. I cannot go more into the practical part of the manu- facture of these non-acid finings than to say that if you take 56 lbs. of ordinary isinglass (leaf is the best, per- haps, at 4s. or 5s. per lb.), cover it with water, and then add eight gallons of sulphurous acid solution—1032 gravity—you will obtain a pure gelatinous mass, which may in the course of two or three days be diluted with water and rubbed through sieves, in order to be ready for immediate use. Such finings should always smell of sulphurous acid, which being present in a free and un- altered state, prevents any kind of decomposition setting in. No actual solution of gelatine takes place in any case, unless the solvent agent exist at a high temperature, and indeed, if solution were effected, no fining action by the use of it would result. The object of this steeping is to so soften the material as to enable you to bring it into a state of proper