Low Gravity Beers

LOW GRAVITY BEERS

by “MIDLAND” in “Journal of the Operative Brewers’ Guild” (Sept. 1917)

The present chaotic state of the brewing trade, both with regard to the choice of material and the sale of the finished article, makes any remarks on methods of brewing somewhat futile; but if we consider the future there can be no doubt that beers of low gravity will be more in demand than in pre-war days, and the old type of heavy, full drinking mild ale will become a thing of the past, and if a normal output is once more reached beer will not be consumed as quickly as it is at present, and consequently the difficulties of producing a good beer will be increased rather than diminished. Now, whatever methods of brewing may be adopted, the basis of all good beer is sound material, and this is more especially the case with weak beers.

The malt should be made from sound material and be well cured, under-cured malts being liable to produce beers which are fretty and drifting in character.

A fairly high percentage of malt substitutes should be used to reduce the albuminous matter, which, if present in excess, makes the beer more susceptible to the influence of atmospheric changes, and at the same time affects the stability. Low gravity beers are never so stable owing to the low percentage of alcohol, which is a natural preservative, so that anything which would be liable to increase instability should be avoided.

The sugar should be of the best quality. Some of the low-grade cane sugars contain a large amount of impurities, which not only produce early acidity in the beer, but also affect the flavor.

The initial heats should be kept up, and the length of infusion curtailed.

Many brewers reduce the quantity of hops when brewing light beers, but this is a mistake. More preservative matter is required in light beers, and a delicate flavor should be aimed at.

The wort should be well boiled, and the excess proteid matter eliminated by wort agitation in the hop back and cooler.

The fermentation of weak gravity beers is always a difficult matter, especially in the summer, the lack of yeast nutriment often causing a fretty fermentation which affects the clarification in cask, the beer frequently developing early acidity.

The difficulty of keeping the yeast in sound condition is greatly increased. Low fermentation heats should be used, and the gyle made up of a strong and weak wort which can be blended at rack. By this method the yeast can be collected from a wort containing sufficient food for the yeast.  Frequent rousing should also be resorted to in order to oxygenate the yeast.

Pure air plants should be installed in the refrigerator room, in order to protect the wort from wild yeast contamination, which has a much greater chance of developing in weak beers.

Care should be taken to see that no undue agitation takes place at racking, otherwise the gas will be expelled, leaving the beer flat and insipid.

The cask plant must be sweet and clean. Any defects in this respect will be quickly shown in weak beers, which soon develop abnormal flavors.

Taken all round, it is much easier to brew a beer of good quality, so that increased care and attention is necessary when dealing with light beers.