(1), crushing, stalk removal and crushing: pulp and sweat separation. Stem removal: The fruit stalk has a green stalk flavor, and the fruit stalk will be preserved unless extra tannins are needed in the wine. (2) After alcohol fermentation and soaking, the grapes are crushed to remove impurities, and then transported to a fermentation container for fermentation. Yeast can come from grapes themselves or be artificially added. The fermentation process lasted for 4~ 10 days, and tannin and pigment in grape skin penetrated into grape juice. The kneading process of tannin and pigment is called impregnation. Impregnation time varies from a few days to several weeks. Soft fermented "new wine" with low tannin content will have a short soaking time; When brewing red wine that can be stored for a long time, it will take a long time to soak because it needs enough tannins. (3) Changing the container The purpose of changing the container is to separate the skin residue from the original wine and end the impregnation process. After removing the skin residue from the container, the wine is squeezed out. The wine squeezed from skin residue has dark color, high tannin content and bitter taste. (4) Lactic acid fermentation In the brewing process of red wine, a kind of side fermentation called lactic acid fermentation is usually carried out. By-fermentation is to use lactic acid bacteria to transform sour malic acid in wine into softer and more stable lactic acid.

Well, I don't know the format or anything ... Your teacher's homework is well arranged, but it's a little troublesome ... I don't have time to do it now (in fact, you should do it yourself). This is an encyclopedia. Delete it yourself and make one. If not, you can read the encyclopedia and combine it with reality ~