Abstract:Osmotic treatment combined with hot air drying was used in this study for improving the quality of preserved peaches, and its effect on the drying characteristics was assessed. The results showed that compared with direct drying, osmotic treatment could shorten the drying time and improve the drying efficiency by removing the most free water before drying. In addition, the physicochemical qualities of preserved peaches treated by osmosis were better than that of direct drying. Preserved peaches of osmotic treatment presented fresh color, low hardness, and the higher vitamin C content. Moreover, total phenol contents, antioxidant capacities, and microstructure of preserved peaches treated by osmosis were also better maintained. Above effects were more obvious in the vacuum osmotic treatment. The correlation analysis indicated that hardness was extremely significant negative correlated with vitamin C content and L* value were obtained. Vitamin C content was extremely significant positive correlated with L* value and significant positive correlated with ferric reducing antioxidant power (FRAP) and DPPH· scavenging capacity. Total phenol content was extremely significant positive correlated with FRAP and DPPH· scavenging capacity. FRAP was extremely significant positive correlated with DPPH· scavenging capacity. The clustering analysis indicated that three groups samples were divided into two categories, direct drying and atmospheric osmotic treatment as one category, and vacuum osmotic treatment as one category. The physicochemical qualities were divided into three categories, hardness as one category, L* value and vitamin C content as one category, total phenol content, FRAP and DPPH· scavenging capacity as one category. Therefore, vacuum osmotic treatment combined with hot air drying could effectively shorten the drying time and improve the quality of preserved peaches, which was a suitable processing method for preserved peaches.