Research on Far-infrared and Hot Airflow Drying of Xianggu Mushroom

In this paper,a series of drying tests on lentinus Xianggu Mushroom have been conducted with far-infrared and convective hot airflow drying oven, Dehydrating characteristic and temperature characteristic were observed.The indexes of quality of lentinus edodes,dehydrating rate and energy consumption were evaluated through four-factor (former-stage drying method and temperature, latter-stage drying method and temperature, moisture content when drying is changed and middle postponed time)and four-level orthogonal design method. Orders of importance of four factors were analyzed. By way of composite treatment of three indexes,the better combination consists of former-stage airflow 50℃,latter-stage far-infrared 65℃,moisture content 70% and middle postponed time 2 hours.Regression index-equations were established,on the basis of the four-factor (former-temperature,latter-temperature, airflow velocity and moisture content when temperature is changed) quadratic regressive orthogonal test. Order of importance of four factors were discussed. The composite object of three indexes was studied. By means of objective nonlinear programming method,the optimal combination consists of former-temperature 52. 9℃, latter-temperature 66. 7℃.airflow velocity 0. 13m/s and moisture content 70. 2%The far-infrared plus airflow drying on lentinus edodes was compared with far-infrared united with hot airflow, and the former is superior.