Citric acid is an important organic acid, also known as citric acid, colorless crystal, often containing a molecule of crystal water, odorless, strong acid and soluble in water. Its calcium salts dissolve easily in cold water, which is commonly used to identify and isolate citric acid. When crystallization is controlled, the appropriate temperature can be obtained without water citric acid. There are a lot of USES for industry, food, cosmetics, etc. At room temperature, the citric acid is a colorless translucent crystal or white grain or white crystalline powder, odorless and very acidic, and the moisture in the moist air is delirious. It can exist in the form of a hydrate or a hydrate: when the citric acid crystallizes from the hot water, it produces a hydrate. Crystallization in cold water creates a hydrate. A hydrate when heated to 78 oC will get no hydrate decomposition. At 15 degrees Celsius, citric acid can be dissolved in anhydrous ethanol.According to domestic and international statistics, the total consumption of the beverage industry account for 75%~80% of the total citric acid production. Citric acid juice is one of the natural ingredients, not only give the fruit flavor, but also solubilization buffer, antioxidant effect, the drink sugar, flavor, pigment and other ingredients blend of coordination, formation of harmonic taste and aroma, can increase resistance the antiseptic effect of microorganisms.