The processing time of the microwave vacuum drying at 70 °C was found to be shorter (1.5 h)compared to that of convective drying (3.5 h). But, microwave vacuum drying at high power (600 W) led to a significant loss of β-carotenes. In summary,microwave drying at moderate power causes a low loss of β-carotenes while reducing operation time (Mayer-Miebach et al.,2005).Hu,Zhang,Mujumdar, Xiao, and Sun (2006, 2007) investigated the hot air and vacuum microwave drying of edamames and found that sequentially combining hot air and vacuum microwave drying provided better drying results compared to that of vacuum microwave drying or air drying