Meat Processing

These are all condensed phosphates, differing by chain length and by counter ion. Pyrophosphates, including TetraSodium Pyrophosphate and Tetrapotassium Pyrophosphate, act most directly on muscle protein, loosening the actomyosin complex so meat holds added water, but they dissolve slowly in cold brine. Sodium Tripolyphosphate is the common working choice because it dissolves better and hydrolyses towards pyrophosphate in the meat. Sodium Hexametaphosphate is a long chain glassy phosphate that dissolves readily and binds metal ions rather than acting strongly on protein.

The potassium salts exist for sodium reduction, are priced above their sodium equivalents and bring a bitterness risk at higher doses. In practice the choice is often a blend, and the useful comparison points are phosphorus pentoxide content, pH in solution, dissolution rate at brine temperature and particle size, since a phosphate that has not dissolved does nothing.