Wine Fermentation
Winemaking is a great hobby, a pastime that has existed for well over 2,000 years. As with any hobby, the most important attributes to possess are experience and wisdom, and with the multitude of factors in winemaking, a single misstep could transform a tasty brew into a sour mess.
However, by having the right knowledge to hand before embarking on your first attempt, you will surprise yourself.
In this short introduction we’ll deal with the fermentation process.
Winemaking consists of two fermentation stations, otherwise known as the primary and secondary. During the primary stage, aerobic fermentation takes place, while anaerobic fermentation occurs in the secondary stage.
Aerobic fermentation means that oxygen is required for the series of chemical reactions that ultimately transform sugar into ethanol and CO2. This stage of fermentation can take as long as a week to as little as four days. In general, about 70 percent of all fermentation takes place during this period. Don’t get nervous if your wine starts to foam, it’s normal during aerobic fermentation. The reason for the primary/aerobic stage is the chance for the yeast to multiply, during which the container vessel must be open to the air. As for the actual numbers, the yeast counts grows in multiples from 100 to 200 times.
The secondary fermentation stage is where an air-lock is applied to the wine vessel so that the brew is deprived of oxygen. At this stage, the yeast switches into an anaerobic fermentation process. The remaining 30 percent of fermentation occurs during this stage, which lasts as long as three weeks to as little as two, depending on the state of the wine. Anaerobic fermentation slows down over time as the sugar and other levels drop in the vessel. Actually, this stage is the most important, as when the yeast stop multiplying, they begin to produce alcohol.
A last factor in fermentation is the temperature, which affects the speed of the yeast, both in their multiplication and alcohol production. The general rule of thumb is 72 degrees Fahrenheit, and if the temperature is too low then the yeast won’t function. On the other hand, if the temperature is too high, the yeast will perform fine except the wine’s flavor will be impacted. This is due to the excess production of enzymes and growth of bacteria.
Filed Under wine fermentation |
Tagged With fermentation, hone wine making, wine fermentation