Effects of different drying methods on drying kinetics and physicochemical properties of Chrysanthemum morifolium Ramat

The effects of infrared-assisted hot-air drying(IR-HAD),temperature,humidity controlled hot-air drying(THC-HAD),and hot-air drying(HAD)on the drying kinetics,physicochemical properties,chlorogenic acid content and microstructure of chrysanthemum were experimentally examined.The results showed that the drying time reduced with increasing air drying temperature,with IR-HAD needing the shortest drying time,followed by THC-HAD and HAD.The effective moisture diffusivities(Deff)of chrysanthemum under IR-HAD,THC-HAD,and HAD at 60℃ were 3.22×10^(-9) m^(2)/s,2.19×10^(-9) m^(2)/s,and 2.89×10^(-9) m^(2)/s,respectively.IR-HAD preserved chrysanthemum surface color better than THC-HAD and HAD,whereas the THC-HAD samples obtained higher water holding capacity(WHC),water binding capacity(WBC),and chlorogenic acid content.Additionally,peroxidase(POD)residual activity of the samples decreased with increasing blanching time.The current work provides a theoretical basis for the drying of chrysanthemum.