Effect of Hot Air Reservoir and Insulator Tray in the Development of Vacuum Freeze Drying

Abstract

The Objective of this work is to know effect of inserting hot air from reservoir to the process of vacuum freeze drying. Tentacle of jelly fish as sample with constant weight 50 g and placed at insulator and teflon container which isolated, the samples were freeze dried with condition at experiment varying between inserting and without inserting hot air at temperature 27°C and also heating from heat loss condenser. The result of experiment shows that while inserting hot air into vacuum freeze drying make pressure rise in until pressure reach 40 mbar. And this phenomena make material evaporation and this event cant be done in vacuum freeze drying. And when without hot air reservoir the pressure can reach 3.5 mbar and the subimation can be done in this process. Vacuum freeze drying process without hot air reservoir need time 12.5 hours and for vacuum freeze drying with hot air reservoir need time 11 hour to drying 50 g of jelly fish tentacle. For process with insulator tray the material can be done in 22,7 hour with internal freezing. From this experiment can be concluded that for vacuum freeze drying with inserting hot air need more ability of vacuum pump specially in flowrate and ultimate vacuum to keep the chamber pressure below triple point condition.