Molecular form. C₆H₈O₇. Citric acid (CA) is an important organic acid. It is a colorless crystal, odorless, with a strong acidic taste, soluble in water, and is a natural preservative and food additive. Application field Food industry Citric acid is an organic acid produced by biochemical methods in the world, citric acid and salts are one of the pillar products of fermentation industry, mainly used in the food industry, such as acid, solvent, buffer, antioxidant, deodorant, flavor enhancer, gelling agent, toner and so on. In terms of food additives, it is mainly used in carbonated drinks, juice drinks, lactic acid drinks and other cool drinks and pickled products, and its demand is changed by the change of seasonal climate. Citric acid accounts for about 2/3 of the total consumption of sour agents. Adding citric acid to canned fruit can maintain or improve the flavor of the fruit, increase the acidity of certain fruits with low acidity when canning (reducing pH), weaken the heat resistance of microorganisms and inhibit their growth, and prevent the bacterial swelling and destruction that often occurs in canned fruits with low acidity. The addition of citric acid as a sour agent in candy is easy to harmonize with the fruit flavor. The use of citric acid in gel food such as paste and jelly can effectively reduce the negative charge of pectin, so as to make the hydrogen bond between pectin molecules to gel. In the processing of canned vegetables, some vegetables are alkaline reaction, the use of citric acid as a pH adjustment agent, not only can play a seasoning role, but also to maintain its quality. Citric acid has the properties of chelating and regulating pH value, which can increase the performance of antioxidant, inhibit enzyme activity and prolong the shelf life of food in the processing of frozen food.Metal cleaning Citric acid is an organic acid produced by microbial fermentation, which is widely used in the production of detergent, and its own specificity and chelation play an active role. Citric acid in the actual use of the process, has a good performance, mainly in terms of safety is more prominent, the preparation of citric acid raw materials are derived from food, which is safe food grade microorganisms. The use of citric acid will not affect the environment, it is easy to degrade under the action of microorganisms and heat, and its own chelating ability is also relatively strong. The main citrate has a strong chelating ability for manganese ion and iron ion, and the use effect is also relatively prominent. The corrosion inhibition of citric acid in detergent is also more prominent, pickling as a more important link in chemical cleaning, compared with inorganic acid, the acidity of citric acid is relatively weak, so the corrosion of the equipment is relatively small, the safety and reliability of citric acid cleaning is relatively strong, the waste liquid is also relatively easy to deal with, and will not cause harm to the human body. Citric acid is an organic acid produced by microbial fermentation, which is widely used in the production of detergent, and its own specificity and chelation play an active role. Citric acid in the actual use of the process, has a good performance, mainly in terms of safety is more prominent, the preparation of citric acid raw materials are derived from food, which is safe food grade microorganisms. The use of citric acid will not affect the environment, it is easy to degrade under the action of microorganisms and heat, and its own chelating ability is also relatively strong. The main citrate has a strong chelating ability for manganese ion and iron ion, and the use effect is also relatively prominent. The corrosion inhibition of citric acid in detergent is also more prominent, pickling as a more important link in chemical cleaning, compared with inorganic acid, the acidity of citric acid is relatively weak, so the corrosion of the equipment is relatively small, the safety and reliability of citric acid cleaning is relatively strong, the waste liquid is also relatively easy to deal with, and will not cause harm to the human body.