Abstract:In order to overcome the natural limitations of potato starch，a rapid viscosity analyzer was used to study effect of high-pressure microjet treatment on the paste characteristics of potato starch.Confocal laser scanning microscopy and Raman spectroscopy were used to study the microstructure and ordered molecular structure of potato starch.The influence of high-pressure microjet treatment on the characteristics of potato starch paste was analyzed according to particle size distribution and apparent amylopectin content.The results revealed that high-pressure microjet treatment might significantly reduce the viscosity of potato starch paste.Treatment at a pressure of 80 MPa resulted in aggregation inside the potato starch granules，improved definition of the growth rings，ordered the starch molecular structure，and increased the crystallinity.Under high pressures ranging between 120 MPa-160 MPa，high-pressure microfluidization treatment resulted in many damaged starch granules and disordered internal molecular structure，which significantly increased the apparent amylose content，reduced the strength of the Raman peaks，and significantly reduced the viscosity of the paste.The results indicated that the mechanical force generated by high-pressure microfluidization penetrated the potato granules，leading to significant changes in structure and paste properties of the potato starch.