PHOSPHATE CRYSTALS IN RAW CURED HAM

The storage of raw cured ham at refrigeration temperatures sometimes c auses translucent crystals to form in the muscles after a few days. Th e composition of the crystals was determined and they were found to co nsist of Na2PO4H.7H2O and Na2PO4H.12H2O. The crystals dissolve in the water of crystallization as the temperature rises. High NaCl and phosp hate concentrations, low humidity levels and a high pH in the muscle f avour the development of these crystals when the ham is stored at refr igeration temperatures. A high relative humidity facilitates the devel opment of phosphate crystals in the outer part of the ham. The P2O5/pr otein ratio declines during the process, especially during salting (be cause of water exudation) and postsalting (because of crystallization in the outer part of the ham). The P2O5/humidity ratio is always highe r in the drier areas.