It is not even worth trying to discuss all the diseases of wine, because most of them are so rare, that there is little chance of encountering them. Especially if we follow the rules of hygiene. However, two or three problems are quite common when making wine and it is worth finding out, how to deal with them, to save the liquor. Most often there are two types of turbidity, which, however, with the right knowledge can be avoided.
Pectin turbidity causes an excessive amount of mucus substances, which contain some fruits (for example. in plums or gooseberries – fruits great for jam, but causing trouble in wine production). To avoid turbidity, enzymes which break down pectins must be added to the must; we use them according to the directions on the packaging. If the wine still becomes cloudy, you need to check the content of pectins. For this we take 85 ml of methyl alcohol, 28 ml of wine and mix thoroughly.
If after a while gelatinous clots precipitate, this will indicate the presence of pectins. Such wine can be clarified, adding a teaspoon of pectolytic enzyme (Polish textbooks recommend clarifying with gelatin or tannin – note. crowd.) and setting them aside for a few days in a warm place. Then the liquid should be removed, and if it is still not clear – filter.
Another disadvantage of wine is starch turbidity, which often appears in cereal wines. To determine, whether starch is the cause of the lack of clarity, pour a little drink on a white plate and add a few drops of iodine. If black spots appear, that is,, that the wine contains starch. We can get rid of it in the following way:: 14 g amylase add to 85 ml of water. Leave the solution on 2 Hours, shaking the bottle every now and then. We heat the wine to a temperature of 76 ° C and keep it through 20 Minutes. Cool to 38°C and add the amylase solution, mixing thoroughly. After an hour, heat the wine again to 76° C and hold it for 10 Minutes. After complete cooling, the sediment should sink to the bottom – then we proceed to the collection of wine. As you can see, you have to work a lot at it. So it's better to add amylase to the must right away (a teaspoon on 4,5 litre of must), to prevent turbidity.
The third popular imperfection of wine is too little power or poor essentiality. Usually it depends on too little tannin content. This can be remedied, adding to the wine a few drops of tannin solution or a glass of strong tea on 4,5 liter of liquid (the first variant is better, because we supply wine with a certain amount of tannin, while the power of tea weakens as a result of contact with alcohol). We do it, when the wine is clear, but even before ripening.
One more problem, with which we can come into contact, appears during fermentation. Wine sours, that is, it gradually transforms into vinegar. This is probably the worst ailment, because this process can be stopped early enough, but we often orient ourselves in the moment, when it's too late. Usually, wine sours due to poor storage, contact with air, the presence of fruit flies or too high a temperature. Note, that the temperature on top of the working must is several degrees higher than in the lower parts. Too high a temperature can kill yeast and at the same time accelerate the growth of Mycaderma aceti bacteria, which are responsible for the formation of vinegar.
With a sensitive sense of smell, we will immediately realize, that something bad is happening with wine. We must then act immediately - add potassium metabisulphite to the wine and set aside for 24 Hours. During this time we prepare the leaven from the same amount of yeast as at the beginning, and when they start working, add a little acidified wine (no more than leaven). When the solution begins to ferment again, pour another portion of wine and repeat this action, until we use up the whole gander. Remember to sterilize the gander after soured wine and cork and fermentation tube.
However, probably the most common problem is the cessation of fermentation. For some reason, the yeast did not finish its work, resulting in an excessively sweet wine. Here are some reasons for stopping the fermentation process:
1. Zaoctowanie.
2. Excessive sugar content, what causes, that yeast suffocates. However, if the yeast has produced the right amount of alcohol, and the wine is too sweet anyway, it does not depend on fermentation, but is an error in calculating the proportion of must components.
3. Presence of carbon dioxide. The accumulation of gas in the wine will be prevented by a fermentation tube, but it is also worth shaking the gander sometimes, so that the dioxide gets out.
4. Too little yeast. This is usually due to frequent or too early pouring of the drink.
5. No air access. Between the stopper and the surface of the liquid we should always leave 38 mm space.
6. Acid deficiency. In this case, the wine may have a foreign aftertaste. If we notice it in time, we can add acid.
7. Presence of preservatives. This happens in the case of, when we use long-stored or dried fruit or canned compote. It is therefore necessary to check on the label, whether the product contains preservatives. If we want to make wine from dried fruits, we must first wash them very thoroughly.
8. Temperature. Too high destroys yeast, too low makes, that they remain dormant. Rapid temperature fluctuations can also have the same effect..
9. Not enough medium. Then we just add one more teaspoon.
As a consolation I will add, that wine production, contrary to appearances, is not very complicated. With a bit of luck and keeping the right rules, problems should not occur at all.