Rosemary (Rosmarinus officinalis L) is an aromatic herb and used worldwide for its medicinal as well as for flavoring properties. The present investigation explores the sequential combination of low humidity air (LHA) and radiofrequency (RF) waves for drying of rosemary for improvement of product quality. The two sequential drying approaches were studied, namely, RF followed by LHA (RF + LHA), and LHA followed by RF (LHA + RF) in comparison with hot air (HA), LHA at 40 °C, and RF (1.8 A, 40 °C) drying alone. Quality of dried rosemary was estimated in terms of retention of volatiles and phytochemicals and compared with freeze-dried (FD) product. The LHA + RF sequential approach significantly reduced the drying time by 60 % and 40 % as well as energy consumption by 27 and 40 % compared with HA and LHA drying, respectively. RF drying required the shortest drying time (120 min) but produced an inferior quality product. The LHA + RF dried rosemary had bright green color and retained higher content of essential oil (86 %), ascorbic acid (81 %), polyphenols (88 %), carnosic (81 %) and rosmarinic acid (76 %) compared with RF + LHA. Oxygenated monterpenes represented 60 % of volatile compounds and α-pinene, eucalyptol, camphor, d-verbenone were majorly contributing to rosemary flavor. A principal component analysis demonstrated that rosemary dried by LHA + RF had higher volatiles and quality close to FD. Overall, results provide a basis for potential application of sequential drying using LHA + RF for energy-efficient and accelerated drying of other heat-sensitive herbs with better preservation of phytochemicals and volatile compounds.

迷迭香（迷迭香）L）是一种芳香草药，在世界范围内因其药用价值和增香作用而使用。本研究探索了低湿度空气（LHA）和射频（RF）波的顺序组合以干燥迷迭香以提高产品质量。与热空气（HA），40°C的LHA和RF（1.8 A）相比，研究了两种依次干燥的方法，即先进行RF再加LHA（RF + LHA），再进行LHA再加RF（LHA + RF）。 ，40°C）单独干燥。干燥迷迭香的质量根据挥发物和植物化学物质的保留率进行估算，并与冷冻干燥（FD）产品进行比较。与HA和LHA干燥相比，LHA + RF顺序方法显着减少了60％和40％的干燥时间以及27％和40％的能耗。RF干燥需要最短的干燥时间（120分钟），但生产的产品质量较差。与RF相比，LHA + RF干迷迭香具有亮绿色，保留了较高含量的精油（86％），抗坏血酸（81％），多酚（88％），肌肽酸（81％）和迷迭香酸（76％） + LHA。氧化的萜烯占60％的挥发性化合物，而α-pine烯，桉树精，樟脑，d-马洛酮主要是迷迭香的味道。主成分分析表明，经LHA + RF干燥的迷迭香具有较高的挥发性，质量接近FD。总体而言，结果为使用LHA + RF进行顺序干燥以提高能源效率和加速干燥其他热敏感草药并更好地保存植物化学物质和挥发性化合物提供了基础。