该研究采用超声波辅热联合抗坏血酸(ultrasound assist heat combined with ascorbic acid, UHA)预处理结合超声波辅助冷冻干燥法干制胡萝卜，并与漂烫预处理结合冷冻干燥以及漂烫预处理结合热风干燥方法进行比较，分析3种干制方法对胡萝卜品质的影响。结果表明，胡萝卜样品经UHA预处理结合超声波辅助冷冻干燥后，体积缩减了17.78%；外部和芯部穿刺力变小，色泽变化相对较小；胡萝卜素含量为(69.51±0.20) mg/100g，Vc含量(48.02±0.62) mg/100g，复水率6.93，均为各处理中最高。经UHA预处理结合超声波辅助冷冻干燥后的胡萝卜样品在产品质构、胡萝卜素含量、Vc含量、复水率等指标方面都有较好表现，显示出了超声波应用于果蔬冷冻干燥生产中的技术优势。

Freeze-dried fruits and vegetables can greatly preserve the original nutritional value and sensory quality of the food. However, freeze-dried food are not popular in food consumption field due to low drying rate, long drying time and high energy consumption. In this study, carrots were processed by three kinds of method: UHA pretreatment combined with ultrasonic assisted freeze drying, blanching pretreatment with hot air drying and blanching pretreatment combined with freeze drying. The qualities of carrots after three processes were compared. After UHA pretreatment and ultrasonic assisted freeze drying, the volume of carrots sample was decreased by 17.78%; puncture force in external and core decreased, and the change of color were relatively small; carotene content was (69.51±0.20) mg/100g, Vc content was (48.02±0.62) mg/100g and rehydration rate was 6.93, which were the highest in all treatments. The ultrasonic group had better performance in terms of product's texture, carotene content, Vc content and rehydration rate, which showed the superiority of ultrasonic technology in the freeze drying of fruits and vegetables.