Sodium tripolyphosphate (STPP) is an alkaline salt, with a formula Na5P3O10 that will raise the pH of meats and seafood, enough to increase their water-holding capacity.
Sodium tripolyphosphate (STPP) is a chemical that has many uses in industry, ranging from an ingredient in cleaning products to a food preservative. Also known by alternate names like pentasodium salt or triphosphoric acid, the substance falls into the classification Generally Regarded as Safe (GRAS), which means that past use of the chemical has presented no risk to health. It can also be found in some paints and ceramic products, among other uses.
One of the common usages of STPP is as an ingredient in detergents and soaps. Most gel, liquid, tablet, and powder forms of both laundry and dishwasher detergent contain it. Its key function is that it allows surfactants, which are molecules that help dissolve surface dirt, to work at their full potential. The chemical can also soften hard water for easier foaming and cleaning, and it helps prevent dirt from sticking to the surfaces of the object being cleaned. Many general household cleaning products, including surface and toilet cleaners, contain STPP.
Sodium tripolyphosphate is also used to preserve foods such as red meats, poultry, and seafood, helping them to retain their tenderness and moisture during storage and transport. Pet food and animal feed can also be treated with it, serving the same general purpose as it does in human food. STPP also has been used to help preserve the quality of drinks such as milk and fruit juices.
Applications of Sodium tripolyphosphate
A Powerful Cleaning Agent
Sodium tripolyphosphate is used in a variety of cleaning products. It improves the ability of various ingredients in the detergent to penetrate the fibers of clothes (as well as other surfaces and materials to be cleaned) more deeply, and aids in foaming and bubbling. Therefore, most chemical plants that make sodium tripolyphosphate list “detergents” as the primary area of use for this chemical.
Sodium tripolyphosphate also gives a fresh appearance to meat and seafood while slowing down spoilage. The chemical helps to preserve the natural color of meat and fish and improves their texture. This is done by improving the water-holding capacity of animal products and consequently slowing down their drying.
Because sodium tripolyphosphate can improve the appearance of seafood like shrimp and scallops, there is some concern that unscrupulous salespeople may sell products that are not fresh to consumers who cannot see the signs that the items have started to go bad. Although it cannot be used specifically for this purpose, this chemical also holds in water, making the seafood heavier and therefore more expensive. Some food quality experts recommend asking a fishmonger or other salesperson for seafood that has not been treated with this chemical.
Tanning Agent for Leather
Sodium tripolyphosphate is listed as a tanning agent for leather. Interestingly, the chemical is also used as an oil contamination resistance agent in paper production. So, it can both help manufacturers apply the right color to a medium as well as keep unwanted color away.
Other uses of sodium tripolyphosphate include petroleum refining, metallurgy, mine applications and water treatment. The last application is made possible by its pH buffering ability, meaning that it can “soften” acidic water by neutralizing its acidity. This quality is one of the reasons it is added to detergents.