INFLUENCE OF PRE-TREATMENT ON DRYING BEHAVIOR OF BROCCOLI FLORETS

摘要

The thin layer drying of broccoli florets is experimentally investigated in a convective dryer.Drying behavior of broccoli florets was examined in a convective thin layer dryer with forced convection at a fixed air flow rate of 0.5 ms-1 and drying air temperature of 40, 60 and 80°C to optimize the drying rate.In order to investigate the impact of different pretreatments, row samples were undergone three pretreatments, namely stepwise blanching in hot water, steam blanching and osmotic pretreatment. The results indicate that treating the broccoli florets prior to drying would improve the drying rate.However between the three of pretreatments that where investigated in this study blanching in hot water and steam blanching have shown the most outstanding effect on reducing the drying time.