摘要：Sodium phosphates , polyphosphates, and citrates are melting salts (emulsifying agents) most commonly used in the manufacture of process cheese either alone or in mixtures . Their role during processing is to sequester calcium in the natural cheese, to solubilize protein and increase its hydration and swelling, to facilitate emul sification of fat , and to adjust and stabilize pH. Changes taking place in natural cheese during processing can be studied by microscopy. Micrographs demonstrating the emulsification of fat , presence of salt crystals, and partial solubilization of protein in labo ratory- made and commercial process cheeses have been used to illustrate the various effects of the emulsifying agents. Optical, particularly polarizing and fluorescence microscopy provides rapid information. Electron microscopy reveals greater detai 1. In combination with energy dispersive spectrometry, electron microscopy can be used to analyze the chemical composition of salt crystals in the process cheese. However, detailed studies of the relationships existing among the microstructure of the process cheese, its composition , and physical properties such as consistency, spreadability, capability of remelting etc. have yet to be carried out.
关键词：Cheese; Citrates; Emulsifying agents; Light microscopy; Melting salts; Microstructure of cheese; Phosphates; Process Cheese; Scanning Electron Microscopy; Transmission electron microscopy
