A Practical Treatise on Brewing/Winter Brewing
WINTER BREWING.
It is a very common observation, that any one can brew in winter, and certainly the, chances of brewing successfully are much in favour of that season. In the first place, there is much less risk of the worts getting tainted during the process than in summer: secondly, the yeast, which during summer will sometimes become unfit for use in a very few hours, is not in winter liable to any such speedy changes; and will even keep for weeks in good working trim: thirdly, the stagnant, or even running water, which, from necessity, is often used in brewing, is in winter much less impregnated with organic matter and impurities than during summer: and thus no such bad effects need be apprehended in cold weather.
If, therefore, the brewhouse be so constructed as to avoid electro-chemical agency, the chances (so called) are much in favour of winter brewing.
Even in this season, wherever any galvanic agency takes place, the process of fermentation is quite as irregular as during summer, and the results are equally uncertain.
In some brewhouses, particularly in the country, the tun-rooms, or chambers in which the fermenting tuns are placed, are so situated as to be affected by every change of temperature. The fermentations in the said tun-rooms must consequently suffer from any sudden change. The great danger arises from a very sudden fall; for instance, we often find that the thermometer will fall 20° or even 30° in the course of a night, and when the tun-rooms are so situated as to be liable to the same change from the sudden decrease in temperature, the fermentations will often become stationary, and cannot be made to progress, unless the temperature be again raised by artificial means.
For this purpose, it is a common practice in small concerns, to fill small casks with boiling water, and place them in the fermenting tuns, changing the water in the said casks, until the desired effect is produced. Others, where there are metal regulators in the tuns, run some hot water through them for the same purpose: this we have seen attended with bad consequences, whether from galvanism or not, We are not prepared to say. It is a practice which we do not recommend.
Mode of accelerating Fermentation when Languid.
A mode different from either, we have uniformly found successful; and it produces the desired effect much more quickly. A very slight rise in the temperature will again promote the fermentation; and the more speedily the required heat can be communicated, the better the effect.
If, therefore, brewing is going on next day, run a certain portion of either the first or second worts, as circumstances may require, into the stationary gyle-tun. Let them be as hot as possible; if only just off the boil, so much the better; about one gallon to a barrel, or even less may be enough.
If no brewing is going on, heat up the requisite quantity of worts, taken from the stationary gyle-tun, to the boiling temperature, or if there be no easy means of doing this, use in the same way about an equal quantity of boiling water. At the same time light a fire in the tun-room to raise the temperature. A little additional yeast set working at a temperature of about 80°, will materially assist.