Drying characteristics and kinetics of lotus seeds using microwave vacuum drying

The drying characteristics of lotus( Nelumbo nucifera Gaertn.) seeds preserved by microwave vacuum drying( MVD) were investigated under various drying parameters,including microwave power density and vacuum degree.It was observed that there was no constant drying rate period,and the entire drying process occurred in the falling- rate period.Microwave power density and vacuum degree had a positive effect on the drying rate and drying time( p < 0.05). Higher drying rates and shorter drying time were obtained with higher microwave power density and higher vacuum degree.Six thin- layer the proposed models was evaluated by using the determination of coefficient( R2),root means square error( RMSE) and reduced chi-square( χ2).Tian model showed a better fit to the experimental drying data with higher R2,lower RMSE,SSE and χ2,as compared to other models.This new model could exactly describe and predict the moisture content of lotus seeds during MVD process.