Abstract: In this paper, the effect of high hydrostatic pressure (HHP) treatment at different pressures (150, 300 and 450 MPa) for 10 min at 25 ℃ on the texture, rheology and microstructure of processed cream cheese low in saturated fatty acids was investigated. The textural characteristics of spreadability, firmness, adhesiveness and cohesiveness were measured by a texture analyzer. The microstructure was observed under a scanning electron microscope, and the rheological characteristics were analyzed by a rheometer. The correlation of changes in pressure with the water content, water activity and pH and textural characteristics was analyzed by the SPSS software. The results showed that with the increase in pressure, moisture content did not obviously change overall, while the water activity of the cream cheese treated at 150 MPa was significantly higher than that of the other cream cheese groups (P < 0.05). The greater the pressure, the higher the pH of the cheese. The pressure was positively correlated with moisture content, with a correlation coefficient of 0.646, but negatively correlated with water activity, with a correlation coefficient of ?0.346. The pressure had a significantly positive correlation with pH, spreadability, firmness, cohesiveness and adhesiveness, with correlation coefficients of 0.963, 0.959, 0.951, 0.956 and 0.956, respectively. HHP treatment could reduce the dependence of cheese viscosity on temperature and increase the stability of cheese network microstructure. Moreover, the storage modulus and loss modulus of the cheeses treated at 150 and 450 MPa were higher than those of the control group, and the viscoelasticity was better than that of the control group. HHP treatment changed the microstructure of the cheese. The greater pressure resulted in a denser microstructure with fewer holes, making the protein matrix smoother and more homogeneous. In summary, HHP treatment has a close relationship with the texture, rheology and microstructure of cheese. This study can provide useful reference for the application of HHP in cheese processing.

Key words: cream cheese; high hydrostatic pressure treatment; texture characteristics; rheological characteristics; microstructure