Sticking Ferments
When fermentation stops before the maximum alcohol the yeast can make is actually made, we say that fermentation has stuck. The main cause of this is too high or too Iowa temperature. Also, lack of acid or tannin or both. Now, provided the recipes are followed, and the fermenting mead kept warm, fermentation should not ’stick’, but sometimes it does. Where it sticks when only about 2% below the maximum alcohol, nothing much is lost. In fact, you might waste a lot of time in trying to get fermentation on the go again. 2% is not important, so if you obviously have a good mead with near enough the alcohol content you aimed at, be satisfied rather than try to make it better. But where a dry mead was aimed at, a dry mead should result. This is because not enough sugar was in the original must to slow up fermentation. And since dry mead is preferred in this case, fermentation must be induced to recommence.
To define the reason for a ferment having ’stuck’ is difficult for beginners - especially when they have added tannin and acid and kept their musts warm. But here is the usual cause, over-warmth or not warm enough. Where it is clear that a must has become too warm, allow it to become quite cold and then warm it again gradually, but be careful this time not to let it become over-heated. Where it has become cold, gradual warming by keeping in a warm place will usually get fermentation on the go again. On no account, attempt to heat the must quickly. If these two remedies fail after a few days of trial, the need for a tiny additional amount of tannin or acid may be indicated, and this should be tried. Just a few drops of strong, freshly-made tea or a few - three or four - crystals of citric acid should be added. Where crystals are not available, a few drops of lemon juice should be tried. If all this fails, then it could be that all nutrient matter has been used up and a further half to whole nutrient tablet should be crushed and added. After each of the recommended additions, give the must three or four days before adding anything else. It often needs this period of time to get a sticking ferment on the go again. For example, if you try extra acid, wait three or four days to see if fermentation gets going again, if it does not, then try something else I have recommended.
Use of Fermentation Lock
The use of the fermentation lock has already been described in the brewing and cider-making chapters. Here it is necessary only to say that we use it in mead making to ensure maximum alcohol is made and to prevent airborne diseases reaching the must. Follow directions already given in the chapters mentioned above and fit the lock at the time given in the recipes.