气介超声干燥水果及其机制的研究

Study on Fruit Drying by Airborne Ultrasound and its Mechanism

气介超声可在常温下去除水分,对干燥热敏性水果有突出优势。该文利用有限元仿真软件和实验研究了气介超声在干燥过程产生的微流现象,分析了气介超声对苹果片微观结构的影响,以及在干燥过程中超声功率对水果含水率的影响。结果表明,气介超声干燥后的苹果组织孔隙显著增大,这将有利于苹果内部的水分扩散,同时气介超声能更好地维持样品的微观结构,与未加超声作用的苹果片相比,气介超声处理后的苹果片含水率显著降低,且干燥速率能在短时间内得到迅速提升。上述结果对理解气介超声干燥机制有参考价值。

The airborne ultrasound can be used to remove the moisture at room temperature,which has outstanding advantages for drying heat-sensitive fruits.This paper investigates the microflow phenomenon the airborne ultrasound during the drying process based on the finite element simulation software and experiments.The effect of airborne ultrasound on the microstructure of apple slices and the effect of the ultrasonic power on the moisture content of fruit during the drying process are studied.The result shows that the tissue porosity of apple after airborne ultrasound drying treatment are significantly enlarged,which is beneficial to the diffusion of moisture inside the apple,at the same time,the airborne ultrasound drying can better maintain the microstructure of the sample.Compared with the apple slices without ultrasound treatment,the moisture content of the apple slices after airborne ultrasound treating has been reduced significantly,and the drying rate can rapidly increase in a short time.The above-mentioned results have reference value for understanding the mechanism of airborne ultrasound drying.