Sodium Tripolyphosphate (STPP)

What's Sodium Tripolyphosphate (STPP)?
A widely used food additive/cleaning aid

Sodium Tripolyphosphate (STPP) or โซเดียมไตรโพลีฟอสเฟต is a sodium salt of triphosphoric acid, well-melting in the water. Gotten from the reaction between sodium hydroxide and phosphoric acid, it is a white powder, well-melting in the water , and high stability.

Note: STPP is not caustic soda (Caustic = sodium hydroxide, is a strong base.)

STPP is widely used in cleaning industry (industry and household), food industry, animal food, metal, paint, pulp, and ceramic particularly in the manufacturing of detergents and floor/bathroom cleaner
Another's name: Pentasodium Triphosphate, Sodium Triphosphate

STPP is a food additive that is commonly used for

Preservation/ Color retention of food
Decrease the color and flavor changing in the food
Enhances water retention in meat and seafood
Helps maintain shape and texture—firm, tender, and elastic
Adjusts water quality and reduces hardness during processing

Beyond its use in food, STPP also functions as a detergent builder
such as laundry detergents, floor cleaners, and metal surface care products

Categories Food Industry, Cosmetic Industry, All products

Product Details

Industries usage

Food Industry

- Processed seafood: Shrimp, fish, squid — helps retain freshness and reduce water loss
- Processed meats: Sausages, pork rolls, meatballs, fermented pork — improves firmness and texture
- Seasonings and sauces: Enhances flavor and stabilizes product color
- Bakery products: Improves softness and structural integrity
- Beverages: Balances pH and prevents sedimentation

Others industry

Used as a builder in detergents, industrial cleaners, and general cleaning products
Applied in textile manufacturing and metal cleaning processes

Standards and Safety
STPP is a commonly used food additive and is approved for safe use within legal limits under Thai Ministry of Public Health regulations (B.E. 2547). For example, phosphate compounds in cured meat products such as sausages, Chinese sausages, ham, and smoked pork leg must not exceed 3,000 mg/kg of product.
Caution: STPP may cause irritation upon direct contact. Avoid inhalation and contact with eyes or skin.

General Guidelines for Using STPP in Food

- Use according to formulation and legal limits (depending on product type)
- Typically applied in solution form for better dispersion and pH control
- Often combined with salt and other phosphate types to enhance water retention and texture
- Note: Optimal dosage depends on formulation, process, and product type. Pilot testing is recommended for production-scale use.

Packaging and storage

Appearance: White powder or granules, water-soluble
Packaging: Standard industrial bags (typically 25 kg)
Storage: Keep in tightly sealed containers, away from moisture, sunlight, and heat

The frequently asked question (FAQ)
Q: Is STPP the same as caustic soda?
A: Not at all. STPP is a phosphate compound used as a food additive and cleaning aid. Caustic soda (sodium hydroxide) is a strong alkali used for cleaning and pH adjustment, with highly corrosive properties.

Q: Why is STPP used in meat products?
A: To enhance water retention, maintain shape, improve texture (firm, tender, elastic), preserve color, and reduce moisture loss during freezing or cooking.

Q: Is STPP safe?
A: Yes, when used within legally approved limits and appropriate formulations.