Clarifying the "component-structure-function" mechanism in processed mozzarella cheese: the mechanistic role of fat,...

The functional properties of cheese are the macroscopic manifestation of its internal structure, however, there is a lack of systematic research on the "component-structure-function" correlation mechanism of processed cheese. This study investigated fat, protein and water interactions during processed mozzarella formation and their impact on cheese quality and structure. On a microscopic scale, the intermolecular forces and microstructural observations were carried out to further clarify the role of different components in the "component-structure-function" of the cheese. Increasing the protein content (from 18.2% to 20.2%) and reducing the fat content (from 25.3% to 22.8%), alongside a slight increase in moisture (from 52.1% to 52.6%), significantly strengthened the cheese matrix structure at a constant total solid level (∼47.5%), resulting in enhanced textural hardness and greater springiness as evidenced by rheological analysis. This compositional adjustment improved the emulsification degree and reduced fat globule size (D_[4,3]) by 37.02%. Mechanistically, excessive fat hinders continuous protein network formation, while dynamic water migration actively governs the structural development. This study clarified the relationship between different components and the functional properties (stretchability and meltability) of processed mozzarella cheese and provided theoretical insights for optimizing the formulation design of processed mozzarella cheese.