E451(ii) – Pentapotassium triphosphate

Additive E451(ii) — pentapotassium triphosphate is a subtype of the food additive E451 from the polyphosphates group. Also known as potassium tripolyphosphate, KTPP (from English Potassium Tripolyphosphate). The chemical formula is K₅P₃O₁₀.

Industrial production is based on calcination of potassium dihydrogen phosphate (KH₂PO₄) and dipotassium hydrogen phosphate (K₂HPO₄) at around 500 °C:

2KH₂PO₄ + 3K₂HPO₄ → K₅P₃O₁₀ + 4H₂O

Potassium tripolyphosphate is a white powder, highly soluble in water and exhibits low hygroscopicity. Additive E451(ii) also has mild alkaline properties and, compared to E451(i), contains potassium instead of sodium, making it more suitable for products with reduced sodium content. Additionally, E451(ii) has less impact on the taste of the finished product.

In the food industry, additive E451(ii) is used as a stabilizer, moisture-retaining agent, and acidity regulator. It is added to meat and fish products, seafood, and frozen semi-finished products to preserve juiciness and improve texture. Sometimes it is used in sports and dietary nutrition where sodium level control is required.

More detailed information about the triphosphates group, their properties, and effects on the human body can be found in the article about food additive E451.