My childhood friend left for Chisinau (Moldova) 26 years ago and only now decided to return back to Russia. It is believed that Moldova is distinguished by the most delicious sweet fruits, as well as the juiciest grapes. Almost everyone in Moldova drinks wine for any reason, and there are even special wine routes for tourists around the country.
During the time spent in Moldova, a friend learned how to make very tasty wine and upon arrival to visit us, he gave useful advice, which is used by many winemakers. He began by saying that before you start making wine, you need to stock up on a raw egg ...
It so happened that we, like many, will very soon start harvesting our grapes, so this advice is just right for us! We will follow him!
There are more than a hundred different recipes for making wine, ranging from varietal (from one grape variety) and ending with blended, when several are mixed wine materials, for example different varieties of grapes or pears and cherries, grapes and apples, etc. Fruits can be left intact, or you can expose to the process crush... different fruits and berries suggest different ways of handling them, but the idea is the same - wine is the result of fermentation, on which the quality of the final product depends, therefore it is important to correctly start this process and monitor it!
Today we are talking about grape wine, so further we are talking about it ...
Grape juice has such a parameter as sugar content, this amount of sugar is called the density of the must. This is an important characteristic! The more the grapes are under the sun, the higher the proportion of sugar in the berry. And the higher it is, the greater the concentration of alcohol per volume unit of wine.
Very often winemakers do not get a good wine at home due to its low alcohol content. This overtakes the winemaker when using grapes that have not reached the desired sugar content, without which the normal fermentation process is simply impossible. To bring sugar back to normal, you need to "artificially" raise it - add the required amount of granulated sugar to the wort. But how do you know if you need to add sugar or not?
After 20-30 hours, the fermentation process starts and the sugar begins to transform into alcohol. At this very moment, it is important to define spirituality. And to determine it, we dip a whole raw egg into the wort!
A chicken egg serves as an indicator, and if it floats up, forming an islet with a diameter of 2-2.5 cm, then the alcoholic content of the wine is exactly 11-13% by volume. In this case, an amazing dry wine is obtained, completely non-acidic in taste! Absolutely! The egg shows this parameter very accurately and this value fits exactly into the GOST framework (from 9 to 14% vol.)
What does physics say?
If you look at this from the point of view of the laws of physics, then everything is simple here. An egg always sinks in ordinary water, because its density is higher than the density of water. But, as soon as we begin to increase the density of water, no matter what salt or sugar, then an object with a lower density will begin to float. In a practical way, it was found out several decades ago that a part of the egg that appeared from the wort by 2 cm indicates the ideal density of this wort itself.
The method is good in that you do not need to have a hydrometer, or scales, or a measuring container. It is enough just for the next day (after 30-40 hours) to lower the raw egg into the wort.
And that's all, thank you for your attention and I hope the article has become useful to you!