为实现枸杞单次大批量干燥的增质提效，设计制造了满足1 125 kg枸杞鲜果的常温真空干燥系统。在空载能力测试的基础上，采用侧抽、端抽等不同方式开展制干效能研究，并进行了枸杞干燥工艺试验验证。试验结果表明：设备的真空能力及供热能力满足设计要求。枸杞常温真空干燥过程中的最大失水速率为4 kg/h，随干燥时间逐渐下降为1.5 kg/h。侧抽真空方式干燥时间相比端抽、组合抽分别缩短7.00%、3.13%，单位能耗除湿量增大29.27%、19.23%。枸杞优质干果比例随干燥水温的下降而逐渐增大（54%~79%），汽泡果比例逐渐随干燥温度的下降逐渐减少。干燥箱局部温湿度均匀性是影响干果成品比例的重要因素。研究结果为4 吨级枸杞常温真空干燥系统开发奠定了基础，对果蔬类、中草药等常温真空干燥系统的开发以及枸杞真空干燥成果的品质优化具有参考价值。

To improve the quality and efficiency of single-batch mass drying of wolfberry, a room-temperature vacuum drying system was designed and manufactured to have a capacity to dry 1 125 kg of fresh wolfberry fruits per batch. On the basis of no-load test results, the drying efficiency of the system for wolfberry was studied by side pumping, end pumping, and combined pumping. The vacuum capacity and heating capacity of the system were experimentally proved to meet the design requirements. During vacuum drying at room temperature, the water loss rate of wolfberry peaked at 4 kg/h and then gradually decreased to 1.5 kg/h with drying time. Compared with end pumping and combined pumping, side pumping resulted in a shorter drying time (7.00% and 3.13% less, respectively) and a higher dehumidification efficiency (29.27% and 19.23% higher, respectively). As the drying temperature decreased (from 60 to 53 ℃), the proportion of high-quality dried wolfberry fruits gradually increased (from 54% to 79%), and the proportion of air-filled wolfberry fruits gradually decreased. Local temperature and humidity uniformity in the drying oven is an important factor affecting these proportions in the final dried wolfberry products. The research results lay a foundation for the development of a room-temperature vacuum-drying system with a capacity to dry 4 tons of fresh wolfberry fruits per batch, while providing a reference for the development of these systems for fruits, vegetables, and Chinese herbs as well as for optimizing the final vacuum-dried products of wolfberry.

国家自然科学基金资助项目（51875452）