Using a Thermometer
Most chemists, such as Boots and Timothy Whites, and many ironmongers stock thermometers covering all ranges of readings. The range best for brewing is from about 50 to boiling; if it goes beyond boiling point it will not matter. Many operators brewing in the simplest fashion seem to manage without one, but it is best to have one handy as it means that temperatures may be checked as required and this checking results in far more accurate brewing which, in turn, makes for far better beers.
When you get your thermometer, take my tip and put it in cold water - all of it - and bring to the boil and hold there for about one minute. This will harden it so that when it is put into high temperature liquids it will not break. It is very probable that all this talk about using a thermometer and hydrometer gives the impression to beginners that home brewing is a highly technical and complicated business - nothing would be further from the truth. The fact is that in using these simple instruments you are making the job much more simple and much more certain. Without them - particularly the thermometer - disaster can overtake you in the early stages, but this would not become evident until much later on when you might discover that, owing to having had the wrong temperature at the wrong time, there is an immovable starch cloud or that the beer lacks flavor or perhaps has gone far more bitter than it should have done.
The hydrometer can, of course, be done without, but as explained in the section covering this instrument, using it makes for safe working, gives you details of how fermentation is progressing, and allows you at a glance to calculate how much sugar to add to give a certain percentage of alcohol.
So don’t stint on these important items and don’t for heaven’s sake imagine this business to be complicated. When you have all the utensils and ingredients ready and have read through the details here once or twice, everything will become very clear and very simple to put into operation.
The fermentation lock beginners need not use a fermentation lock during the early days of beer making. But when they have had a bit of experience they may find it very useful - I do myself. Readers already making wines must forgive me for boring them by repeating details they already know about. In wine making we use a fermentation lock to ensure that the fermenting wine is kept safe from wild yeasts and bacteria and to cut off the air and oxygen supply so that the yeast, which must have oxygen, turns to the sugar for it, thus producing more alcohol than it would if it obtained oxygen from the atmosphere. It is a fact that high alcohol wines cannot be made without a fermentation lock.
In beer making we use a fermentation lock during the later stages of production and in order to keep the fermenting wort free of wild yeast and bacteria. We also use it so that we can put the fermenting beer into jars, thus freeing the fermentation vessel for another batch.
As will be seen, after three or four days, fermentation of the beer slows down; it is at this stage that it may be put into jars. If put into jars during the vigorous ferment, the yeast will be forced up through the lock to such an extent that you will have beery yeast all over the place.
But if the lock is fitted to jars filled to within four or five inches of the tops with slower fermenting beer, there will be no bother. Fermentation locks are supplied with bungs already fitted for about 25 6d. One, or maybe two is all the home brewer will need. Before fitting the lock rinse it in some of the sterilizing solution and then stand it on its bung downwards in a cup of the solution to make sure the cork is purified. It may then be fitted to the jar. A little of the solution is then poured in the open end or dropped in with an eye-drops dispenser. The gas being generated inside the jar will push the solution up to one side and bubbles will pass through. The solution closes up so quickly that airborne diseases are prevented from gaining access. The lock may be left in place until all fermentation has ceased or until you are satisfied that it has gone on long enough to leave the right amount of sugar left unfermented and the beer is ready for bottling. This, of course, depends on whether you are making draught beer, or are adding sugar to draught beer to produce a gaseous beer, or whether you are using a hydrometer to ascertain how much sugar is left unfermented. All this may seem to complicate matters, but as soon as you have made a few brews all this will fall neatly into the pattern of things.