Abstract:To improve the drying efficiency of native potato flour, the effect of pectinase enzymolysis pretreatment with different time (60-80min) on hot air drying characteristics of raw mashed potato and physicochemical and processing properties of prepared pectinase-treated native potato flour (PNPF) were investigated. The results showed that the pectin content and initial water content of raw mashed potato were reduced after pectinase hydrolysis treatment , consequently improved the drying rate and caused greatly reduction of the drying time by up to 6.32%-7.81%. The contents of pectin, ash and protein in PNPF significantly decreased after pectinase treatment. Furthermore, amylose, amylopectin and total starch contents in PNPF increased significantly, and the relative crystallinity of starch and iodine blue value of PNPF decreased. At the same time, PNPF had higher solubility and swelling degree, and oil holding capacity was reduced significantly compared with non-treated flour. The water holding capacity was increased by 40.49%-49.58%. Moreover, the freeze-thaw water syneresis rate of PNPF decreased by 26.23%-62.11%, and the PNPF prepared by 180 min pectinase enzymolysis treatment exhibited the best freeze-thaw stability. The gelatinization characteristic analysis showed that peak temperature of PNPF decreased, the peak time shortened, the breakdown value increased, and the final viscosity and retrogradation decreased. In conclusion,pectinase enzymolysis pretreatment could improve hot air drying characteristics of raw mashed potato, shorten the drying time, and significantly improve the basic physicochemical and processing properties of the native potato flour.