***<<<Article still being written. I post it for the sake of collaborators.>>***
“Phosphates and water-binding in animal tissue. Sodium Tripolyphosphates () is the most common phosphate added to processed meats. It is often used with sodium hexametaphosphate to increase tolerance to calcium irons that exist in meat curing brines. Ortho- and pyrophosphates often precipitate if used in brines containing substantial amounts of calcium.
The mechanism by which alkaline phosphates and polyphosphates enhance meat hydration is not clearly understood despite extensive studies. The action may involve:
- the influence of pH changes;
- effects of ionic strength;
- specific interactions of phosphate anions with divalent cations and myofibrillar proteins;
- it may be that calcium complexing and a resulting loosening of the tissue structure is a major function of polyphosphates;
- binding of the polyphosphate anion to proteins and simultaneous cleavage of cross-linkages between actin and myosin results in increased electrostatic repulsion between peptide chains and a swelling of the muscle system. If exterior water is available, it can then be taken up in an immobilized state within the loosened protein network;
- Because ionic strength has been increased the interaction between proteins is perhaps reduced to a point where part of the myofibrillar proteins form a colloidal solution.
- In sausages, the addition of sodium chloride
(Fennema, O. R.; 1996: 778)
Fennema, O. R.. 1996. Food Chemistry, Third Edition. Marcel Dekker, Inc..