Modelling of the Moisture Dynamic Process and Effects on Multiple Functional Components of Gardenia jasminoides Ellis with Different Drying Methods

In order to investigate the effects of different drying methods and temperatures on the moisture removal and quality of the finished products during the drying process of Gardenia jasminoides Ellis,the Weibull distribution function was used to fit the drying kinetic curve,and the content of geniposide,crocin I,crocin Ⅱ and genipin-1-β-gentiobioside in the dried products was determined. The results showed that the Weibull distribution function did well in simulating the drying curves of the Gardenia jasminoides Ellis under the experimental conditions(R²=0.9936~0.9998).The drying process of the infrared drying belonged to the falling-rate drying period(β<1). The drying rate of vacuum drying and hot air drying present a rising trend at the beginning but a downward trend as time went on(β>1). The scale parameter α decreased as the temperature increased,and the α was related to the different drying methods,but the difference narrowed with the increase of temperature. The activation energy for moisture diffusion of hot air drying,infrared drying,and vacuum drying were 40.744,54.73,and 87.46 kJ/mol,respectively. Under the same drying method,the retention of crocin I,crocin Ⅱ and genipin-1-β-gentiobioside showed an increasing trend,and the retention of geniposide did not show any increasing or decreasing trend with the increased of drying temperature;The results of comprehensive evaluation which based on the content of functional components showed that the quality of the sample obtained by infrared drying at 50 ℃ was better,while considered the drying time and drying energy consumption,the drying method of infrared drying at 70 ℃ could be uesed as a suitable drying method for Gardenia jasminoides Ellis.