在吸附干燥实验装置上测定了薰衣草干燥曲线,研究其干燥过程动力学特性;实验考察了吸附干燥条件对薰衣草中药用成分(总黄酮、木犀草素和芹菜素)的影响,采用正交实验优化干燥工艺条件.结果表明:降低干燥介质相对湿度、提高干燥温度和干燥介质空速度,可明显提高薰衣草吸附干燥速率;相对湿度是影响总黄酮含量的主要因素,木犀草素对干燥温度最为敏感.薰衣草吸附干燥较适宜的工艺条件为:温度30℃,干燥介质相对湿度16%,空速905 h-1;在此条件下,干燥薰衣草中总黄酮含量为2.673%,芹菜素含量为0.976%,木犀草素含量为0.0245%.Midilli-Kucuk模型可较好拟合薰衣草吸附干燥特性曲线;在较适宜条件下,薰衣草吸附干燥过程动力学方程为:WR=0.9834exp(-5.484×10-4×t1.46)-6.2934t.%Adsorption drying curves were measured with a low-temperature adsorption drying apparatus and drying kinetics of lavender was investigated. Effects of adsorption drying conditions on the contents of total flavonoid, luteolin and apigenin in dried lavender were studied. The preferred drying conditions were optimized by orthogonal experimental design. The results show that adsorption drying rates of lavender increase rapidly by reducing relative humidity and improving drying temperature/space velocity of drying medium. Relative humidity is a key factor to total flavonoid contents, while drying temperature is a sensitive factor to luteolin contents. The suitable drying process conditions are: drying temperature of 30℃, average relative humidity of 16% and space velocity of 905 h-1. The content of total flavonoids under the optimized conditions is 2.673% and the contents of luteolin and apigenin are 0.976% and 0.0245% in dried lavender, respectively. Midilli-Kucuk mathematical model can well fit the adsorption drying curves. The dynamic equation for lavender adsorption drying process is: WR = 0.9834exp(-5.484×10-4×t1.46)-6.2934t.
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