目的 以枸杞为实验材料，探讨超声波技术对远红外真空干燥过程的影响。方法 将超声波技术应用于枸杞的远红外真空干燥试验，利用自主研制的远红外真空辐射干燥设备，研究在不同超声频率、超声功率和超声处理时间条件下，枸杞的远红外真空干燥特性和其品质的变化规律，并用Weibull函数对干燥过程进行动力学模拟。结果 随着超声频率、超声功率和超声处理时间的增加，干燥时间明显缩短，干燥速率显著增加；Weibull分布函数可以较好地模拟不同超声处理条件下枸杞的远红外真空干燥过程（r²=0.993 9～0.999 2，χ²=0.000 1～0.000 6），尺度参数α随着超声频率、超声功率和超声处理时间的增大总体呈现增加的趋势，形状参数β均大于1；与远红外真空干制品相比，进行超声处理不仅能减少枸杞的有效成分损失，还能缩短其干燥时间，其中超声频率为40 kHz对应单因素试验所得干制品的多糖（812.846 mg/g）最高，当超声功率为80 W时，其对应单因素试验所得枸杞干制品的总黄酮含量最高上升了28.69%，当超声频率为60 kHz时，其对应单因素试验所得枸杞干制品的总酚含量提高了10.11%，当超声处理时间为25 min时，其对应单因素试验所得枸杞干制品的DPPH值提高了14.33%；通过对比不同处理条件下的微观结构图，发现超声波不仅能增加物料表面微孔数量，还能降低对枸杞表皮细胞的损伤。结论 将超声波技术应用于枸杞的远红外真空干燥，强化了枸杞内部的热质传递过程，改善了枸杞干果的品质，可以为枸杞干燥技术的发展提供技术指导。

Objective To investigate the effect of ultrasonic technology on the far infrared vacuum drying process by using Lycium barbarum as the test material. Methods The far-infrared vacuum drying test of L. barbarum was performed by ultrasonic technology. Using the independently developed far-infrared vacuum radiation drying equipment to study the far-infrared vacuum drying characteristics and quality change law of L. barbarum under different ultrasonic frequency, ultrasonic power and ultrasonic treatment time; And the Weibull function was used to simulate the drying process dynamically. Results With the increase of ultrasonic frequency, ultrasonic power and ultrasonic treatment time, the drying time was significantly shortened, and the drying rate was significantly increased. The Weibull distribution function could better simulate the far-infrared vacuum drying process of L. barbarum under different ultrasonic treatment conditions (r²=0.993 9-0.999 2, χ²=0.000 1-0.000 6), the scale parameter α generally increased with the increase of ultrasonic frequency, ultrasonic power and ultrasonic processing time, and the shape parameter β was greater than 1; Compared with far-infrared vacuum dried products, ultrasonic treatment can not only reduce the loss of active ingredients of L. barbarum, but also shorten its drying time. Among them, the polysaccharides (812.846 mg/g) of the dried products obtained by the single factor test under the condition of 40 kHz ultrasonic frequency was the highest. When the ultrasonic power was 80 W, the total flavone content of L. barbarum after drying increased up to 28.69% in the single factor test. When the ultrasonic frequency was 60 kHz, the total phenol content of the dried L. barbarum products obtained by the single factor test increased by 10.11%. When the ultrasonic treatment time was 25 min, the corresponding DPPH value of dried L. barbarum producta obtained by the single factor test increased by 14.33%; By comparing the microstructure diagrams under different processing conditions, it was found that ultrasonic waves can not only increase the number of micropores in the surface of materials, but also reduce the damage to L. barbarum epidermal cells. Conclusion The application of ultrasonic technology to the far-infrared vacuum drying of L. barbarum strengthens the heat and mass transfer process inside and improves the quality of L. barbarum dried fruit, which can provide technical guidance for the development of L. barbarum drying technology.

R283.6

国家自然科学基金项目（51765003）；甘肃省科技重大专项（2060404）；甘肃农业大学科技创新基金-学科建设基金项目（GSAU-XKJS-2018-187）