Tannin is one of the most important differences between red wine and white wine. White wine is made by separating grape juice from skin residue and fermenting with grape juice. Therefore, the soul of liquor is acid, not tannin. Chemically speaking, tannin is an active molecule with negative charge, and the molecular weight of tannin in red wine is generally between 500 and 3000. In the process of wine tasting, tannin molecules react chemically with saliva protein, which will make the oral surface have a convergent touch, which is usually described as "astringent". If "acidity" is the personality of liquor, then "astringency" is the personality of red wine.

2) Liquor must be peeled, stemmed and pitted before brewing, because there is no need to extract color and tannin. The aging year is generally 1-3 years, the temperature is 25-28 degrees, and the time is short. Red wine doesn't need peeling, just stems and pits. Because there are many tannins (antioxidants) in grape skin, it helps to improve the quality of wine. The aging cycle is different, it only takes 3-5 days for table wine, 8 months for aged wine 12- 18 months, and several years for famous wine under special technology. The temperature is about 18-22 degrees.

3) Tannin in red wine can not only promote blood circulation, but also remove greasy taste, which can prevent arteriosclerosis and cholesterol rising rate, while fruit acid in white wine can remove fishy smell, so it is recognized as the best table wine.