An experiment study of low-temperature vacuum drying on spinach

The low- temperature vacuum drying kinetics of spinach in terms of moisture content, moisture ratio, drying rate had been researched experimentally.The samples was employed to study the drying behaviour at 0, 5, 10℃.The objective of this study was to compare the quality of these spinach in terms of their rehydration ratio, their content of chlorophyll and vitamin C to that low-temperature vacuum dried, hot air dried, and freeze vacuum dried spinach.The results showed that, there was no constant drying rate period.The rehydration ratio of spinach dried during low- temperature drying was 8.0, was greater than hot air drying but less than freeze vacuum drying.Additionally, low- temperature drying was found to yield spinach with relatively high levels of chlorophyll and vitamin C.