Disodium phosphate

Disodium phosphate (CAS 7558-79-4), also known as DSP and classified as E339(ii) in food applications, is an inorganic phosphate salt used across food, pharmaceutical, and industrial water treatment sectors.

Its primary commercial functions are pH buffering, sequestration of metal ions, and stabilization of formulations where consistent acidity control is critical. In food manufacturing, DSP acts as an emulsifying salt and pH regulator.

It is used in processed cheese, instant noodles, and canned products where texture and shelf stability depend on controlled buffering. Pharmaceutical manufacturers use it to prepare buffer solutions for injectable formulations.

It is also utilized in oral liquids and tablet coatings where precise pH maintenance affects drug stability and bioavailability. Water treatment operations rely on DSP to prevent scale formation and corrosion.

It protects boiler systems and cooling towers by sequestering calcium and magnesium ions. It also functions as a dispersing and deflocculating agent in ceramic slips and detergent formulations.

Disodium phosphate is supplied as a white crystalline powder or granules, in both anhydrous and hydrated forms. Recognized grades include food-grade (FCC), USP/BP for pharmaceutical use, and technical grade.

The product is also available in Ph.Eur., EP, and ACS standards depending on the specific industrial requirement. Packaging typically ranges from 25 kg bags to bulk quantities depending on grade and application.