There are several ways to increase the sugar concentration. Most sweet wines are made with varieties with high sugar content (e.g. Saperavi, Rkatsiteli, Tinta Negro). The sweetness is influenced by the climatic conditions in which the harvest is grown (the hotter the summer, the sweeter the fruit). There are two kinds of beverage: variety and blend. To make a sweet varietal, one sort is chosen, while for a coupage, several types are mixed. Peculiarities of making red sweet wine:
- Fermentation is carried out until the alcohol concentration reaches a value at which the yeast dies without having processed all the sugar.
- Fruits are sun-dried, which reduces the moisture content by about 25% and increases the sugar content.
- Infestation with the health-safe fungus "botrytis cinerea" (increases the concentration of sugars) is necessary.
- Fermentation is stopped with cold until the sugar is processed into alcohol (the method is relevant for dessert wines with reduced alcohol content).
- Increasing sugar content by subfreezing (the fruits begin to be harvested after frost so that they are slightly subfreezing).
- Remove sediment by cold stabilization (before bottling, the beverage is kept at a temperature below the OOS).