Abstract:In order to understand the effect of different pretreatments on the hot air drying characteristics and quality of red rose, four different pretreatment methods ,i.e. impregnated 5% citric acid solution, 20% sugar solution, 20% NaCl and citric acid mixed solution and blanching, the pretreated petals were used as the control, to conduct comparative experiments and analysis of hot air drying. Sensory properties (color, total flavonoids, total phenols) and microstructure of red rose were examined, and combined with fuzzy mathematical comprehensive evaluation method for sensory evaluation. The results showed that drying rate of rose petals was influenced significantly by different pretreatment methods especially when the moisture content was high,and there are certain differences in microstructure. The dried red rose products in the 5% citric acid solution pretreatment group required the longest time and the lowest color difference index ΔE; in the 20% sugar solution group, the rehydration ratio was lowest. In the 20% NaCl and citric acid mixed solution group, the highest color difference index ΔE and the highest content of total phenols. The blanching pretreatment group required the shortest time, obtained the highest content of total flavonoids and the highest rehydration ratio. The blanching pretreatment group had the highest sensory score. Under the optimized condition, the drying time, and the color difference index ΔE and the content of total flavonoids and total phenols were 120 min, 18.17±0.54, 3.01, 0.27 mg/g and 1.43 mg/g, respectively. Therefore, the application of blanching as a pretreatment method could improve the quality of dried red rose products.