Citric acid is an important organic acid, also known as citric acid. It is a colorless crystal that often contains one molecule of crystal water. It is odorless, has a strong sour taste, and is easily soluble in water. It has a wide range of uses, covering many fields such as food, medicine, and industry.

In the field of food, as a natural acidifier in terms of acidity regulator, it gives food a sour taste. It is often used in beverages (such as cola, juice), candies (such as lemon candy), canned food, jam, etc. It can improve flavor, enhance appetite, and adjust the pH value of food to prevent deterioration. At the same time, it can synergize with sugar to balance sweetness and sourness. In terms of preservatives, it inhibits the growth of microorganisms such as bacteria and molds, and extends the shelf life of food. It is often used in foods such as soy sauce, pickles, and jelly. In terms of antioxidants, it chelates with metal ions to prevent them from catalyzing oxidation reactions, protecting vitamin C, fat and other ingredients in food from oxidation. It is often used in oily foods and baked products.

In the field of medicine, it is used in the preparation of antibiotics, sulfonamide drugs, etc. in terms of pharmaceutical raw materials. It can also be used as a pH regulator for injections to ensure drug stability and safety. In the field of health care products, it is added to health care products as a food additive to supplement the citric acid needed by the human body and participate in the metabolic process in the body.

In the field of dentistry, in dental treatment, it is used to clean the surface of teeth, remove plaque and tartar, and prepare for subsequent treatment.

In the industrial field, in terms of chemical raw materials, it is used to produce citric acid ester plasticizers, which can be added to plastics and rubbers to increase their flexibility and elasticity. As an intermediate in chemical synthesis, it is used to prepare other organic acids, esters and other compounds. In detergents, it chelates calcium and magnesium ions in water, softens hard water, and enhances the decontamination ability of detergents. It is often used in washing powder and dishwashing liquid.

In other fields, in agriculture, it is used as a feed additive to improve the palatability of feed and promote animal growth. It is also used for soil improvement, regulating soil pH, and increasing soil fertility. In cosmetics, it is added to skin care products, shampoos and other cosmetics to adjust the pH value of the product, and it also has certain antioxidant and moisturizing effects.

The role of citric acid in different fields reflects its versatility and importance, but it should be used in moderation and follow relevant standards and regulations to ensure safety and effectiveness.