The generic term Sodium Phosphate is referred to any sodium salt of phosphoric acid. It has a variety of uses and most commonly is added to food. Sodium phosphates have been studied thoroughly and when used as food additives are generally considered to be safe.
Sodium phosphate can refer to any of the 3 specific compounds but is usually referred to trisodium phosphate (Na3PO4) unless otherwise indicated. The other two compounds are sodium dihydrogen phosphate (NAH2PO4), also known as monosodium phosphate, and disodium hydrogen phosphate (NA2HPO4) which is also known as disodium phosphate.
Some of the purposes sodium phosphates are used for are:
- Surface active agents – serve as a whipping or foaming agent by changing liquid components of foods surface tensions
- Texturizer – disodium hydrogen phosphate serves as a texture modifying agent to change the feel or appearance of a food. Increasing the shelf life of the food can be done by adding a texturizing agent.
- Leavening Agent – to help dough rise in baked products, sodium phosphate may be added. Most commonly as a leavening agent, sodium phosphate is added in the batter for commercial cakes and breaded fish or chicken.
- Neutralizing Agent – by adding sodium phosphate it can prevent the food to become too acidic or alkaline.
- Emulsifier – all of the 3 forms of the sodium phospates can be used as an emulsifier, which allows 2 or more ingredients to disperse uniformly. Specifically, an emulsifier’s most common purpose is in the prevention of oil separation in a mixture. Processed meats, processed cheeses and canned soups are where sodium phosphates are commonly added as emulsifying agents.
- Nutrient – where sodium phosphate is a dietary supplement when added to food as these compounds provide phosphates which are essential nutrients.