disodiumphosphate

Disodium phosphate, formally disodium hydrogen phosphate, is an inorganic salt with the chemical formula Na2HPO4. It appears as a white crystalline substance and is typically sold as an anhydrous salt or in hydrated forms. It is highly soluble in water and, when dissolved, yields the hydrogen phosphate ion (HPO4)2−, producing a basic (alkaline) solution.

Production of disodium phosphate commonly involves the neutralization of phosphoric acid (H3PO4) with a sodium base, such as sodium hydroxide (NaOH) or sodium carbonate (Na2CO3). By controlling the neutralization, the resulting product can be obtained as Na2HPO4, often along with other phosphate salts. It is available in both anhydrous and hydrated forms.

In industry and food production, disodium phosphate serves several roles. It is widely used as a buffering agent and acidity regulator to stabilize pH in processed foods, cheeses, baked goods, canned vegetables, and infant formulas. It also functions as an emulsifier and sequestrant, helping to retain texture, moisture, and color. In detergents and cleaning products, it acts as a water-softening agent that improves cleaning efficiency. In laboratories, it is used in phosphate buffer solutions for pH control in various experiments.

Safety and regulatory status are generally favorable when used within approved limits. Disodium phosphate is permitted as a food additive in many countries and is considered safe for most consumers in typical amounts. Excessive intake can lead to electrolyte imbalance or gastrointestinal discomfort, and individuals with kidney disease or specific health conditions should follow dietary guidance. As with all chemical substances, proper handling and storage are advised.