Citric Acid is the largest organic acid produced by biochemical methods in the world. Citric acid and salts are one of the pillar products of the fermentation industry. They are mainly used in the food industry, such as acid, solvent, buffer, antioxidant, deodorant, flavor enhancer, gelling agent, and toner. [9]
In terms of food additives, it is mainly used for carbonated drinks, fruit juice drinks, lactic acid drinks and other cool drinks and pickled products, and its demand is subject to seasonal climate changes. Citric acid accounts for about 2/3 of the total consumption of acid flavor agent. Adding citric acid to canned fruit can maintain or improve the flavor of fruit, increase the acidity of some fruits with low acidity (lower pH value), weaken the heat resistance of microorganisms and inhibit their growth, and prevent the bacterial can-breaking and damage that often occur in canned fruit with low acidity. Adding citric acid into candy as an acid is easy to coordinate with fruit taste. The use of citric acid in gel food, jam and jelly can effectively reduce the negative charge of pectin, so that the hydrogen bond between pectin molecules can bind to gel. When processing canned vegetables, some vegetables show alkaline reaction. Using citric acid as pH regulator can not only play a role in seasoning, but also maintain its quality. Citric acid has the characteristics of chelation and pH regulation, which can increase the performance of antioxidants, inhibit enzyme activity, and extend the shelf life of foods in the processing of quick-frozen foods.
Metal cleaning
Citric acid is an organic acid produced by microbial fermentation. It is widely used in Detergent production. Its specificity and chelation play a positive role. Citric acid has good performance in the actual use process, mainly in terms of safety. The raw materials for preparation of citric acid are from grain, which is a safe food-grade microorganism. The use of citric acid will not affect the environment. It is easy to degrade under the action of microorganisms and heat. Its own chelating ability is also relatively strong. The main reason is that citrate has relatively strong chelating ability for manganese ion and iron ion, and the use effect is also prominent. The corrosion inhibition of citric acid in detergents is also prominent. As an important part of chemical cleaning, acid pickling is relatively weak compared with inorganic acid. Therefore, the corrosivity of citric acid to equipment is relatively small. The safety and reliability of citric acid cleaning is relatively strong, and the waste liquid is relatively easy to be treated, which will not cause harm to human body.
Fine chemical industry
Citric acid is a kind of fruit acid, which is mainly used to accelerate the renewal of cutin, and is commonly used in lotion, cream, shampoos, whitening products, anti-aging products, acne products, etc. Citric acid can be used as chemical analysis reagent in chemical technology, as experimental reagent, chromatographic analysis reagent and biochemical reagent; Used as complexing agent and masking agent; To prepare buffer solution. The use of citric acid or citrate as a detergent aid can improve the performance of washing products, rapidly precipitate metal ions, prevent pollutants from re-attaching to the fabric, and maintain the necessary alkalinity for washing; Disperse and suspend dirt and ash; It is an excellent chelating agent to improve the performance of surfactant; It can be used as a reagent to test the acid resistance of architectural ceramic tiles. Citric acid-sodium citrate buffer is used for flue gas desulfurization. China is rich in coal resources, which constitute the main part of energy. However, there has been a lack of effective flue gas desulfurization technology, resulting in serious atmospheric SO2 pollution. Because of its low vapor pressure, non-toxic, stable chemical properties and high SO2 absorption rate, citric acid-sodium citrate buffer solution is a desulfurization absorbent with great development value.
Sterilization and coagulation process
The combined action of citric acid and 80 ℃ temperature has a good effect on killing bacterial spores, and can effectively kill the contaminated bacterial spores in the pipeline of hemodialysis machine. Calcium ion must be involved in the formation of prothrombin activator and subsequent coagulation process. Citrate ion and calcium ion can form a soluble complex that is difficult to dissociate, thus reducing the concentration of calcium ion in blood and preventing blood coagulation.
Animal breeding
Citric acid is formed by the carboxylation of acetyl coenzyme A and oxaloacetic acid in the body's tricarboxylic acid cycle, and participates in the metabolism of sugar, fat and protein in the body. Natural citric acid exists in the fruits of plants (such as lemon, orange, pineapple, etc.) and in the bones, muscles and blood of animals. Artificial synthesis is made by fermentation of sugar-containing substances such as sugar, molasses, starch, grapes, etc. Adding citric acid to the formula feed can disinfect, prevent mildew and prevent Salmonella from infecting animal feed. Animal intake of citric acid can reduce the proliferation of pathogens, inhibit the production of toxic metabolites, and improve animal stress.
Agriculture
In November 2022, Chinese scientists found that the selection of organic acids (flavors) such as citric acid was completed in the process of watermelon improvement
