Daily tech terms | citric acid

citric acid

Also known as: citric acid

Definitions: The chemical name is 2-hydroxypropane-1,2,3-tricarboxylic acid. A tricarboxylic acid. It is very versatile, used in the food industry, accounting for more than 75% of the production volume, can be used as a food sour agent, antioxidant, pH regulator, used in cool drinks, jams, fruits and pastries and other foods. It is used in the pharmaceutical industry for about 10%, mainly used as anticoagulants, antidotes, flavoring agents and so on.

Discipline: Botany_Phytochemistry_Main chemical components of plants

Related terms: citric acid synthase acidity regulator lactate

Image source: Visual China

【Further reading】

Citric acid, also known as citric acid, is a medium strength organic acid. Citric acid is a natural preservative produced in citrus fruits and can also be used as a sour additive in food and beverages. Many kinds of fruits and vegetables, especially citrus fruits, contain more citric acid. Lemons and lime contain a lot of citric acid, which can reach up to 8% after drying. "Citric acid" is named after a fruit of the citrus genus, citrate.

Citric acid has a mild and refreshing sour taste, and is widely used as a food additive in the manufacture of various beverages, wines, candies, snacks, canned juices, dairy products and other foods. In all organic acid markets, citric acid has a relatively large market share, and there is currently no sour taste agent that can replace citric acid. In addition to being used as an acidic flavoring agent, citric acid can also be used as an antioxidant in edible oil to improve the sensory properties of food, enhance appetite, and promote the digestion and absorption of calcium and phosphorus substances in the body.

In biochemistry, the citric acid cycle plays an important role in the metabolism of the vast majority of organisms and is a core reaction of biological metabolism. During these chemical reactions, citric acid converts fats, proteins, and sugars into carbon dioxide, which provides energy to higher organisms. Hans Adolf Krebs was awarded the 1953 Nobel Prize in Physiology or Medicine for discovering this series of reactions. These reactions are called the "citric acid cycle", the "tricarboxylic acid cycle" or the "Krebs cycle".

Citric acid can be used as a chemical analysis reagent, chromatographic reagent and biochemical reagent, as a complexing agent, a masking agent, and can also be used to prepare buffer solutions. The use of citric acid or citrate as a builder can improve the performance of washing products, quickly precipitate metal ions, prevent pollutants from reattaching to the fabric, disperse and suspend dirt, improve the performance of surfactants, and is an excellent chelating agent. Citrate-sodium citrate buffer solution is a desulfurization absorber with great development value due to its low vapor pressure, non-toxic, stable chemical properties and high absorption rate of sulfur dioxide.

In everyday life, citric acid can remove scale. The main components of scale are calcium carbonate, magnesium carbonate and other deposits, citric acid solution can react with it to form a water-soluble citrate, so it can be used to clean water dispensers, electric kettles and shower heads. Citric acid also has a good effect of killing bacterial spores, coupled with the fragrant smell of lemon, it is often used as a dish accessory, which is both delicious and refreshing and can enhance appetite, enjoying the reputation of "the king of Western food".