Abstract: To determine the best drying method of Lilium lancifolium, the effects of microwave vacuum drying, vacuum freeze drying, and hot air drying on the quality of Lilium lancifolium were systematically studied and compared. The core indicators including the water content, the polysaccharide content, and the ash content in the Pharmacopoeia of the People's Republic of China（hereinafter referred to as the Pharmacopoeia） were measured. Sensory evaluation was also performed. The results showed that the water content and the ash content of all twelve drying samples conformed to the Pharmacopoeial standards. Except for the treatments of microwave vacuum drying at 80 ℃ for 50 min and hot air drying at 80 ℃ for 5 h, the polysaccharide content of the other ten treatments complied with the Pharmacopoeial standards. Among these treatments, the polysaccharide content of vacuum freeze drying at -70 ℃ for 8 h achieved the highest level, reaching 26.65%. In terms of sensory evaluation, the dried samples of vacuum freeze drying at -70 ℃ and microwave vacuum drying at 70 ℃ for 40 min exhibited better comprehensive quality, while the hot air drying samples had the problems such as darker color and harder texture. In conclusion, vacuum freeze drying at -70 ℃ for 8 h was the optimal drying method for drying Lilium lancifolium, followed by microwave vacuum drying at 70 ℃ for 40 min. This study provided certain theoretical and technical support for the drying processing and upgrading of Lilium lancifolium.

Key words: Lilium lancifolium, drying technology, comparative study, quality, polysaccharide