Composition, microstructure and chemical interactions during the production stages of Mozzarella cheese

Changes in chemical composition, microstructure and chemical interactions before and after the stretching stage of mozzarella cheese processing were investigated. The increased acidity and the decreased pH resulted in the solubilisation of total calcium. The protein matrix became more compact and the size of the fat globules decreased with the incorporation of small individual fat globules, aggregates and fat globules of irregular form into the matrix. The predominant bonds in the curd before the stretching stage were hydrophobic interactions, whereas the number of calcium bonds was minimal. After the stretching stage, the primary bonds responsible for maintaining the cheese structure were calcium bridges, electrostatic interactions and hydrogen bridges. These results clarify important aspects of the bonds involved in the production of this type of cheese.