The chemical formula of calcium carbonate is CaCO₃. It typically comes as a white solid, either crystals or powder. It is odorless, chalky, and flat. It can have a sweetish flavour.Calcium carbonate is not soluble in water. However, it can be emulsified to disperse in water. it is  used in many industries such as pharmaceuticals or as a food additive.

Calcium carbonate is not soluble in water. However, it can be emulsified to disperse in water.

The E number of calcium carbonate is E170. This means that it is classified as a food colour, even thought it has many other uses.

 when use in food it can :

• Control acidity,
• Act as a white food colour,
• Act as a firming agent for vegetables,
• Act as a nutrient for yeasts,
• Add an additional source of calcium

There are a lot of uses of calcium carbonate. It can be found in almost all kinds of foods from dried fruits to canned sardines, also in frozen foods, cereals, aromatized beverages and processed meat and fish products.It can also be a stabilizer, added mainly to dairy products.

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