Chemistry and Rheology of Cheese

The chemistry of cheese and the use of this knowledge to develop a low-fat Mozzarella, now being used in the National School Lunch Program, were investigated. Texture and flavor development in cheese result from complex interactions between fat and protein, which are influenced by other factors such as salt content, pH, and temperature. Enzymes from the rennet and the starter cultures cleave casein molecules resulting in microstructural changes in the curd and forming compounds that impart specific flavors to the cheese. Fat serves as a filler in the protein matrix and as a carrier of flavor; consumers often find low-fat cheese varieties to be harder, less meltable, and less flavorful. These quality and sensory problems are surmountable if manufacturing procedures are adjusted with consideration of the chemistry taking place. The flavor can be enhanced by adding certain adjunct cultures, and the texture and meltability can be improved by processing at lower temperatures, which allows the microorganisms to remain active and break down the protein matrix during storage.