Li Jun, Wan Fangxin, Huang Xiaopeng, Yang Xiaoping, Zang Zepeng, Xu Yanrui, Wu Bowen, Zhang Kaikai, Ma Guojun
College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China.
Foods. 2024 Dec 17;13(24):4071. doi: 10.3390/foods13244071.
To enhance the physicochemical quality, drying efficiency, and nutrient retention of dried products, this study investigated the effects of ultrasonic pretreatment on the radio frequency vacuum (RFV) drying characteristics, microstructure, and retention of natural active substances in slices. The ultrasonic time, power, and frequency were considered as experimental factors. The results showed that, compared with conventional RFV drying, ultrasonic pretreatment reduced the drying time of slices by 20-60 min. The Weibull model accurately described the moisture ratio changes under different pretreatment conditions (R > 0.9984, χ < 2.381 × 10). The optimal retention of polysaccharides, total phenols, total flavonoids, and antioxidants was achieved under pretreatment conditions of 30 min of ultrasonic time, 180 W of ultrasonic power, and 40 kHz of ultrasonic frequency. Furthermore, ultrasonic pretreatment preserved the internal cellular structure of slices, maintaining intact tissue cells and well-defined microchannels. However, a slight reduction in sample color was observed following ultrasound application. In conclusion, ultrasonic pretreatment significantly improved the RFV drying process for slices by enhancing drying efficiency, preserving active ingredients, and optimizing the physicochemical quality of the dried product. This study provides novel insights and methods for optimizing the drying process of , offering a foundation for further research and industrial applications.
为提高干燥产品的物理化学品质、干燥效率和营养成分保留率，本研究考察了超声预处理对切片的射频真空（RFV）干燥特性、微观结构及天然活性物质保留率的影响。将超声时间、功率和频率作为实验因素。结果表明，与传统RFV干燥相比，超声预处理使切片干燥时间缩短了20 - 60分钟。威布尔模型准确描述了不同预处理条件下的水分比变化（R > 0.9984，χ < 2.381 × 10）。在超声时间30分钟、超声功率180瓦、超声频率40千赫的预处理条件下，多糖、总酚、总黄酮和抗氧化剂的保留率达到最佳。此外，超声预处理保留了切片的内部细胞结构，保持了完整的组织细胞和清晰的微通道。然而，超声处理后样品颜色略有降低。总之，超声预处理通过提高干燥效率、保留活性成分和优化干燥产品的物理化学品质，显著改善了切片的RFV干燥过程。本研究为优化[切片名称]的干燥工艺提供了新的见解和方法，为进一步的研究和工业应用奠定了基础。
