Abstract: This study aimed to investigate the rheological characteristics of dietary fiber and yoghurt which added with dietary fiber modified with dynamic high-pressure microfluidization treatment and the effects of dietary fiber modified at different treatment pressures and its addition amount on viscosity of yoghurt. The results showed that the apparent viscosity of dietary fiber at 0.6% concentration increases from 145.3 mPa·s at 40 MPa to 551.6mPa·s at 180 MPa with the treatment pressure riasing,and the apparent viscosity of dietary fiber treated at 80 MPa ascends to 897.9 mPa·s at 1.5% with the concentration rising. The apparent viscosity of yoghurt has the same trend to the dietary fiber,increasing with the increment of treatment pressure and addition amount of dietary fiber ascending,and at the stirring rate of 6 r/min,the viscosity of the yoghurt added with 0.6% dietary fiber treated 80MPa increasing from 6.02 Pa·s to 8.36 Pa·s,which exhits the thixotropic fluid character istics with an orthodox and thick taste.

Key words: dynamic high-pressure microfluidization, dietary fiber, yoghurt, rheology