What is Citric Acid?

Citric acid is a weak acid mostly used as a preservative, and is naturally found in citrus fruits, which are named after it. It is involved in the metabolism of almost all the living beings on Earth.

Concentration of this acid in fruits like orange and grapefruit is 0.005 mol/L, while for limes, this number is 0.30 mol/L. Along with citrus fruits, it is also found in berries like blackberries and raspberries. The concentration can, however, change with variety.

• At room temperature, its pure form attains solid state and is found in the white powdered form. The citric acid formula can help in understanding its chemical nature.
• It gets dissolved in water quite easily.

• It can exist both in monohydrate and anhydrous form. Conversion of citric acid from monohydrate to the anhydrous form takes place by heating at 78 °C.
• At 15 °C, it gets dissolved in anhydrous ethanol.
• It exhibits the property of chelation; which means that its bonds with metals, and minerals are easily formed.

• Many of the chemical properties are similar to that of carboxylic acids. The process of heating citric acid at 175 °C causes decomposition which results in the loss of water and carbon dioxide.
• Jabbir Ibn Hayyan, an Islamic alchemist is credited with its discovery in 8th century A.D.

• C. Wehmer is credited with the discovery of the conversion of sugar to citric acid with the help of Penicillium mold.
• It plays an important role in the process of physiological oxidation of proteins, fats, and carbohydrates into elements such as water and carbon dioxide.

• Citric acid is commonly used as a food additive. This chemical is used for flavoring in various preparations containing Vitamin C.
• It also finds applications in industries. For example, good quality natural cleaners can be made with its application.

• The property of chelation exhibited by it helps the human body digest the desired elements (minerals like calcium) easily.
• Chelation using citric acid helps in the production of calcium supplements. The calcium nitrate supplements get absorbed by the body very easily.

• The property of chelation is not only used in preparation of calcium supplements, but also in products used for softening water. Therefore, it is included in products like detergents and soaps. It is however, necessary to maintain its quantity in shampoos because, excess amount can damage the hair cuticle.

• It is also applicable in the manufacturing of beauty products, bath tablets, and bath fizzes.
• Citric acid in the form of white powder is used for exterior coating of candies.

It can be bought from the pharmacy shops, health food stores, supermarkets, etc.