The most commonly used calcium salt of citric acid is tricalcium dicitrate tetrahydrate, hereinafter referred to as tricalcium citrate. In some countries such as USA, tricalcium citrate is simply denominated calcium citrate. It is produced by complete neutralisation of citric acid with a high purity calcium source such as calcium hydroxide or calcium carbonate.
With its high calcium content of 21%, tricalcium citrate is the most economic calcium salt among the commonly used organic calcium salts.
Tricalcium citrate is supplied as a white, odourless, crystalline powder or fine powder. It is slightly soluble in water and freely soluble in diluted hydrochloric acid. In contrary to other salts, tricalcium citrate is better soluble at lower temperatures (so-called "inverse solubility"). It is practically insoluble in alcohol.
During heat treatment, it is less reactive than other calcium salts due to its inverse solubility. With regard to its significantly better bioavailability, tricalcium citrate is preferred over inorganic calcium sources such as calcium carbonate or calcium phosphate.
Tricalcium citrate meets the requirements of the US Pharmacopeia (USP), the Food Chemicals Codex (FCC), and the Commission Regulation (EU) No. 231/2012 always in their latest versions.
The following granulation types are available:
- Micronised Powder
Tricalcium citrate is supplied in polyethylene lined paper bags. Net quantity is 10, 15, 20 or 25 kg, depending on the individual bulk density of the desired granulation.
- White powder
- Available in different micronised granulations
- Neutral taste
- Slightly soluble in water
- Inverse solubility
- Good bioavailability
- Good compressability
- High compatibility
- 21% Ca-content
- Allergen and GMO free
- Highly bioavailable calcium source in pharmaceuticals, foods and beverages
- pH adjuster
- Sequestering and stabilising agent in food
- Firming agent for fruits and vegetables
- Low reactivity compared to other calcium salts
- Agrochemicals, Fertilisers
- Plastics, Polymers
- Baby Food, Infant Formula
- Cereals, Snacks
- Desserts, Ice Cream
- Fruit Preparations, Sweet Spreads
- Fruits, Vegetables
- Soy Products
- Carbonated Soft Drinks
- Instant Drinks, Syrups
- Juice Drinks
- RTD Tea and Coffee
- Sports and Energy Drinks
- Clinical Nutrition
- OTC, Food Supplements
- Pharmaceutical Products
- Pet Food
- Oral Care
- Surface Care
In Europe, tricalcium citrate is listed as a generally permitted food additive (E 333) and may be added to all foodstuffs, following the "quantum satis" principle as regulated in EU Regulation (EC) No. 1333/2008 (Annex 2), as long as no special regulation restricts the use. In addition to existing national allowances in some countries, tricalcium citrate is on the positive list of the EU Regulation (EC) No. 1925/2006 on food fortification and is allowed in food supplements (Directive 2002/46/EC). It is listed as mineral salt in the EU Regulation (EC) No. 609/2013 on food intended for infants and young children, food for special medical purposes, and total diet replacement for weight control.
The US Food and Drug Administration (FDA) affirmed tricalcium citrate as generally recognised as safe (GRAS) and permitted the use in food with no limitation other than current good manufacturing practice (21CFR §184.1195).