Calcium Phosphates
What it does
Raising agent, anti-caking.
How it's made
Made from phosphate minerals.
Calcium phosphates are the calcium salts of phosphoric acid, a group that includes mono-, di- and tricalcium phosphate. In food they act as raising agents, firming agents, anti-caking agents and calcium fortificants, and they are chemically the same family of compounds that make up the mineral of bones and teeth.
They are manufactured by reacting purified phosphoric acid with a calcium source such as calcium hydroxide (slaked lime) or calcium carbonate. Adjusting the ratio of acid to calcium produces the different salts: monocalcium phosphate is the acidic form used in baking powders, while dicalcium and tricalcium phosphate are less acidic and are used for firming, anti-caking and adding calcium.
The precipitated salts are filtered, washed, dried and milled to a fine white powder. Because they are made from food-grade raw materials and thoroughly washed, the finished phosphates are pure and consistent, and the particular salt is selected to match the job — for example, monocalcium phosphate paired with bicarbonate of soda in self-raising flour.
Possible reactions
Generally safe; excess phosphate concerns in kidney disease.