Effect of high pressure microfluidization on microstructure of mozzarella cheese

Microstructure was compared in low-fat and full-fat mozzarella cheeses prep ared from milk homogenized by microfluidization at various temperatures and pressures. Milk heated to 10, 43, or 54 degreesC and containing 1.0 or 3.2 g fat/100 g fluid milk was homogenized at 34, 103, or 172 MPa prior to che esemaking. Scanning electron microscopy was performed after I d and 6 wk of storage at 4 degreesC. The micrographs should that relatively large fat gl obules were dispersed throughout the casein matrix in each of the cheeses m ade from milk homogenized at 10 degreesC, and in each of the nonhomogenized controls. As expected, fat globules were much smaller in the cheeses made fr om milk homogenized at the higher pressures. Increasing the milk tempera ture also caused the globule size to decrease since the fat became liquid a nd more easily fragmented. The results indicate that both homogenization te mperature and pressure affect development of microstructure in mozzarella c heese. (C) 2000 Academic Press.