Molecular Formula:Na4P2O7;Na4P2O7·10H2O
Molecular Weight: 265.91;446.07
CAS NO.:7722-88-5(Anhydrous);13472-36-1(Decahydrate )
【Structural Formula】
1. Product Property
Food-grade sodium pyrophosphate is a white crystalline powder or granular solid, highly soluble in water but insoluble in alcohol. It has a strong alkaline pH (9.9–10.7 in 10 g/L solution) and acts as a chelating agent for metal ions. The anhydrous form melts at 880°C, while the decahydrate loses water at 100°C. It is hygroscopic, absorbing moisture from air, and hydrolyzes to disodium phosphate when boiled in water
2. Quality Standards
| Parameter | Specification |
| Assay (Na₄P₂O₇) | ≥ 96.5% (anhydrous) / ≥ 98.0% (decahydrate) |
| pH (10 g/L solution) | 9.9–10.7 |
| Arsenic (As) | ≤ 3 mg/kg |
| Heavy Metals (Pb) | ≤ 10 mg/kg |
| Fluoride (F) | ≤ 50 mg/kg |
| Water Insolubles | ≤ 0.2% |
| Phosphate Test | Passes |
| Loss on Ignition | ≤ 0.5% (anhydrous) |
3. Application Scope and Usage
As a food additive, it works as a quality improver. In meat products, it retains moisture, improves tenderness and juiciness. In seafood, it prevents discoloration. Used in dairy to stabilize emulsions, in baked goods to enhance texture. Also functions as a sequestrant in beverages, with usage levels generally 0.05% – 0.5%, following food additive regulations.
4. Package and Storage
Packed in polyethylene – lined woven bags, paper bags, or composite plastic bags, with common net weights like 25kg/50kg. Store in a cool, dry, ventilated warehouse. Avoid moisture, direct sunlight, and contact with acids. Keep sealed to prevent caking and quality deterioration. Shelf life is around 24 months under proper storage conditions.
