Tetrasodium Pyrophosphate (TSPP)

About This Product

Tetrasodium pyrophosphate (TSPP), also called sodium pyrophosphate or tetrasodium diphosphate, is authorised as food additive E450(iii) in the EU and UK. The anhydrous salt has the CAS number 7722-88-5, the formula Na4P2O7 and a molar mass of 265.90 g/mol; a decahydrate also exists but food trade is mainly in the anhydrous white powder or granules. TSPP is strongly alkaline, with a 1 % solution at about pH 10.

In meat and poultry products TSPP is the most active phosphate for improving water holding and bind. It raises the pH of the meat away from the isoelectric point of the muscle proteins and helps dissociate actomyosin, so salt-soluble proteins are extracted more easily. The result is higher cooking yield, better slicing and a juicier texture in cooked ham, sausages, restructured products and marinated poultry. It is normally used in blends with sodium tripolyphosphate or SHMP, with total added phosphate typically around 0.3 % to 0.5 % of meat weight. In seafood it plays a similar role in brines and glazes.

TSPP has several uses outside meat. In potato products it chelates iron and prevents after-cooking darkening, often alongside sodium acid pyrophosphate. In instant puddings and desserts it reacts with milk calcium to set the product without heating. In processed cheese it is one of the emulsifying salts, and in some dairy and protein products it disperses and stabilises proteins. Its low solubility, around 6 to 7 g per 100 ml at room temperature, means it should be dissolved before salt when brines are prepared.

Buyers typically agree the assay on the dried basis, the P2O5 content, the pH of a 1 % solution, loss on drying or ignition, water-insoluble matter, fluoride and heavy metals. The grade should meet the E450(iii) purity criteria in Regulation (EU) No 231/2012 and its GB equivalent, or the FCC or JECFA monograph for other markets. Particle size is worth specifying where TSPP goes into dry blends.

Diphosphates are authorised in specific food categories under Annex II of Regulation (EC) No 1333/2008 and the UK retained equivalent, usually within a group maximum for E338 to E452 expressed as P2O5. Meat preparations have narrower permissions than meat products, so check the current annex for the exact product and add the contribution of every phosphate in the recipe. Declare it by function, such as stabiliser: E450, or as diphosphates.

TSPP is alkaline and irritating to eyes, skin and airways, so use eye protection and dust control and follow the safety data sheet. Store sealed and dry; the anhydrous powder absorbs moisture and cakes. When you enquire, give the application, the form and particle size, the purity standard, whether it will be blended with other phosphates, pack size, annual volume and destination, and the documents you need.