Various methods are used to increase the sugar concentration in sweet red wine. The sweetness of the wine is determined by the type of grapes used, with high sugar content varieties like Saperavi, Rkatsiteli, and Tinta Negro being commonly used. The following are the unique production methods of red sweet wine:
- Fermentation is stopped before all the sugar is converted into alcohol.
- Fruits are sun-dried, which reduces the moisture content and increases the sugar concentration.
- Infestation with the health-safe fungus "botrytis cinerea" is required to increase sugar concentration.
- Fermentation is stopped by cooling until the sugar is converted into alcohol, particularly for dessert wines with low alcohol content.
- Sugar concentration is increased by subfreezing fruits harvested after frost to make them slightly subfreezing.
- Sediments are removed by cold stabilization before bottling by keeping the drink below zero degrees Celsius.