Other names for the additive (synonyms)
General Information
According to the International Numbering System for Food Additives Codex Alimentarius: CXG 36-1989, calcium bicarbonate (food additive E170(ii)) is a subtype of E170 (calcium carbonates).
It is an inorganic compound of natural origin with the chemical formula Ca(HCO₃)₂. Unlike calcium carbonate, this salt is found in nature only in solutions — mainly in underground and mineral waters, where it forms through the interaction of carbon dioxide, water, and limestone. In solid form, calcium bicarbonate cannot be isolated, as it is unstable and decomposes upon heating or storage into calcium carbonate, carbon dioxide, and water.
For the food industry, calcium bicarbonate is synthesized by passing carbon dioxide through a solution of calcium hydroxide or calcium carbonate in water. The resulting solution is used in technological processes, but due to its instability, the substance is rarely applied in finished food products.
The properties of additive E170(ii) limit its use: unlike E170(i), calcium bicarbonate is not used as a colorant or a source of calcium. Its main application is related to acidity regulation and the improvement of water and beverage quality.
In the international standard Codex STAN 192-1995 and in the European Regulation (EC) No 1333/2008, this subtype is not included. In these documents, the term E170 refers exclusively to calcium carbonate.
More details about the health effects and safety of calcium carbonates can be found in the general article about additive E170.