Study On The Characteristics And Technology Of Coriander Hot Air Drying And Its Equilibrium Moisture Content

Hot air drying experiment is one of the important means to study the processing and storage conditions of fresh coriander. Hot air drying characteristics, drying process optimization, drying mathematical model and equilibrium moisture content were studied through the test in this topic.Through single factor experiment, moisture content curves and drying rate curves of the coriander under different technological parameters were drawn, and the effect law of the blanching pretreatment, different hot air temperatures, velocities of the hot air and the thicknesses of the material layer on the drying characteristics and sensory quality of the coriander was studied; By using the method of orthogonal experiment, the drying rate and the rate of water recovery were the evaluation indexes, and through the range and variance analysis of the test results, the influence of the hot air temperature, the velocity and the thickness of material layer on the primary and secondary order and the significant degree of test indexes were obtained. At last, a better combination of drying process parameters was worked out; The test datas were fitted by nonlinear regression method, the drying mathematical model of the relationship between MR and time t in the process of hot air drying was established, and the moisture content of the coriander at any moment in a given drying process is predicted; Through the determination of desorption and absorption equilibrium moisture contents of coriander at different temperatures and relative humidities, the desorption and absorption isotherms were plotted respectively, the effects of the temperature and the relative humidity on the equilibrium moisture content were analyzed, and the method for prolonging the storage period of the dried coriander was determined.