用颜色测量法在线监测真空冻干香蕉含水率

On-line monitoring for moisture content of banana during vacuum freeze-drying based on color mesurement

实时监测真空冷冻干燥过程中果蔬的含水率,不仅可以掌握升华干燥和解析干燥的过程,有助于了解冻干机理,更重要的是可以根据物料实时含水率及时终止冻干,以降低冻干能耗。以香蕉为研究对象,以Matlab颜色测量为技术手段,通过采集样本在一个完整冻干周期中的图像,连续在线监测样本表面R、G、B值的微小变化,并建立颜色变化量和香蕉含水率相关关系模型。结果表明,模型决定系数R2=0.6932,显著性检验概率p<0.0001,说明回归模型极其显著并具有较高的拟合精度。经检验,该方法检测含水率的最大相对误差和最小相对误差分别为4.79%和0.01%,说明方法准确性较好,可以为真空冻干果蔬含水率在线监测提供借鉴和参考。

Real-time monitoring the moisture content of fruits and vegetables during vacuum freeze-drying （VFD） process, not only can master sublimation drying process and help to understand the mechanism of VFD process, more importantly, can terminate the VFD process quickly according to the real-time moisture content, this will led to the lower energy consumption. In this paper, bananas were cut into many tablets, and their surface images were captured by CCD during the whole VFD process. RGB values were calculated using Matlab software. A correlation model with R2=0.6932b and p〈0.0001 between RGB color values and moisture content was established. The result shows that the model is extremely significant and has a high fitting accuracy. Upon examination, the maximum and minimum relative errors of this method were 4.79% and 0.01%, respectively. This indicates that the method is accurate and reliable, and can provide a reference for monitoring moisture content of many other fruits and vegetables.