Citric acid

Author:Prof. Dr. med. Peter Altmeyer

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Last updated on: 29.10.2020

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Synonym(s)

acidum citricum; acidum citricum anhydricum; CAS No 77-92-9; citric acid; Citric acid

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DefinitionThis section has been translated automatically.

Citric acid (INCI designation: citric acid) is the most widespread organic fruit acid in the plant kingdom (tricarboxylic acid = 3 COOH groups). The acid is easily soluble in water, easily soluble in ethanol and glycerol and slightly soluble in ether.

Citric acid is permitted as a food additive under E 330 in Europe.

Citric acid esters of the MDG (mono- and diglycerides of fatty acids) are permitted as food additives under the number E 472d.

Citric acid occurs as a metabolic product in all organisms. Citric acid is found in lemon juice (contains 5-7% citric acid), but also in fruits such as apples, pears, blackberries, raspberries, currants, sour cherries, etc. Citric acid is also found in the blood, urine, muscle and the mammalian myocardium.

Citric acid occurs as an intermediate product in the citrate cycle (also known as the citric acid cycle or cancer cycle), the central cell metabolism cycle of aerobic cells of living beings, which mainly serves the oxidative breakdown of organic substances. In eukaryotes, the citrate cycle takes place in the matrix of the mitochondria.

Citric acid is used in food technology as a flavour corrigent in salads, in lemonades, effervescent tablets, various types of food. Desserts and others. Furthermore it serves as a substitute for vinegar.

It also serves as a preservative. Citric acid reduces oxidation processes, prevents changes in smell, colour and taste and thus the decay of food.

The salts/esters of citric acid are called citrates.

Field of application/useThis section has been translated automatically.

Food additive (E 330)

Dentistry

In detergents

Preservatives and acidifiers in foodstuffs

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Last updated on: 29.10.2020