In the ingredient list of red wine, there can only be grape juice and sulfur dioxide. The sulfur dioxide here is mainly used for sterilization to keep the flavor of red wine pure and fresh. If there are other ingredient lists, be careful. Secondly, red wine is mainly divided into four types: dry, semi-dry, semi-sweet and sweet. The sugar content of each liter of red wine is less than 4 grams, which is dry red wine with astringent taste. The sugar content per liter is 4.1-12g, which is semi-dry, and the taste is friendly to novices. Every liter 12-45g belongs to semi-sweet type, and if the sugar content per liter is more than 15g, it belongs to sweet type, which tastes a bit like sugar water.