| Item |
Details |
| Product Name |
Sodium Tripolyphosphate (STPP) |
| Synonym |
STPP, Sodium Triphosphate, Pentasodium Tripolyphosphate |
| CAS No. |
7758-29-4 |
| E Number |
E 451(i) |
| Molecular Formula |
Na₅P₃O₁₀ |
| Molecular Weight |
367.86 |
| Appearance |
White powder or granules |
| Purity |
≥94.0% (Food Grade) |
| Grade |
Food Grade, Industrial Grade |
| Solubility |
Freely soluble in water, insoluble in ethanol |
| pH Value (1% solution) |
9.5 – 10.4 |
| Executive Standard |
Food Grade: FCC, E 451(i), GB 25558; Industrial Grade: GB/T 9983 |
| Certifications |
ISO9001, HALAL, KOSHER |
| Heavy Metals (as Pb) |
≤ 0.001% |
| Fluoride |
Compliant with international safety standards |
Product Overview
Sodium Tripolyphosphate (STPP), CAS No.: 7758-29-4, E No.: E 451(i) , is a high-purity phosphate additive with excellent sequestering, emulsifying, water-binding and pH stabilizing functions. It features good water solubility, strong chelating capacity and wide compatibility with food ingredients.
It is a multi-functional food additive widely applied in meat and seafood products, processed cheese, dairy products, beverages and various food formulations to improve water retention, stabilize texture, bind metal ions and optimize production performance. It is also widely used as a key auxiliary in detergent formulations and industrial water treatment.
STPP vs KTPP Comparison
Sodium Tripolyphosphate (STPP) and Potassium Tripolyphosphate (KTPP) are both polyphosphates with water retention and chelating functions. The key difference lies in the cation: STPP is the sodium salt, while KTPP is the potassium salt, which directly determines their suitable applications.
| Comparison |
STPP (Sodium Salt) |
KTPP (Potassium Salt) |
| Cation Type |
Sodium salt (Na⁺) |
Potassium salt (K⁺), low-sodium |
| pH (1% solution) |
9.5 – 10.4, stronger alkalinity |
9.2 – 10.0, milder alkalinity |
| Water Retention |
Strong, cost-effective |
Excellent, slightly milder, higher cost |
| Best Applications |
Conventional meat & seafood, processed cheese, detergents, water treatment |
Low-sodium meat & seafood, reduced-sodium dairy and cheese |
| Industrial Use |
Widely used in detergent builder, ceramic, water treatment |
Limited industrial use, mainly food-grade |
| Typical Buyer |
Bulk food processors, detergent raw material buyers |
Premium food brands, low-sodium product formulators |
In short, STPP is the cost-effective choice for conventional meat, seafood and detergent applications, while KTPP is designed for low-sodium food formulations to avoid excessive sodium intake.
Character
Sodium Tripolyphosphate has stable chemical properties and excellent solubility in water. It is an alkaline polyphosphate with strong metal ion chelating ability, effectively binding calcium, magnesium and other metal ions in solution. Food grade STPP is produced through strict purification process with low impurity content, complying with global food additive standards. It shows outstanding water-binding and protein-modifying effects, particularly in meat and seafood processing, helping to improve yield and maintain juicy texture. Industrial grade STPP provides consistent batch quality and is widely used in detergent and water treatment applications.
Main Functions
1.Sequestrant & Chelating Agent — bind calcium, magnesium and other metal ions, inhibit oxidation and discoloration
2.Water Retention Agent — improve water-holding capacity of meat and seafood, reduce cooking loss and maintain juiciness
3.Emulsifying Salt — promote protein emulsification and dispersion, stabilize texture in processed meat and cheese
4.pH Buffer & Stabilizer — maintain alkaline pH range, stabilize food systems during processing and storage
5.Texture Improver — enhance product tenderness, firmness and overall mouthfeel
6.Industrial Auxiliary Agent — key builder in detergent formulations, water treatment and metal surface treatment
Applications
1.Meat & Seafood Processing (Core Application) STPP is widely used in processed meat, seafood and aquatic products as a water-retention and texture-improving agent. It enhances yield, reduces purge loss during storage, and helps maintain tender, juicy and firm texture after cooking.
2.Dairy & Processed Cheese Applied in processed cheese and cheese spreads as an emulsifying salt, promoting smooth melting and uniform texture.
3.Beverage & Functional Food Used as a sequestrant and stabilizer in beverages, protein drinks and functional food systems to prevent turbidity and oxidative deterioration.
4.Detergent & Industrial Fields Industrial grade STPP is widely used as a key builder in synthetic detergent formulations, industrial water treatment, ceramic production and metal surface treatment.
Packaging & Storage
Packaging: 25kg kraft paper bag with inner plastic bag, 1000kg jumbo bag, customized packaging available
Storage: Store in cool, dry and ventilated warehouse, keep packaging sealed; protect from moisture and high temperature
Shelf Life: 24 months under proper storage conditions
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