近红外光谱检测柑橘糖度光照角度可调装置设计与试验  

Design and experiment of light angle adjustable device for measuring sugar content of citrus by near infrared spectroscopy

作　　者：曾贤明 韩龙波 文韬[2] 代兴勇 ZENG Xianming;HAN Longbo;WEN Tao;DAI Xingyong(Hunan Commodity Evaluation Center,Changsha,Hunan 410004,China;College of Mechanical and Electrical Engineering,Central South University of Forestry and Technology,Changsha,Hunan 410004,China)

机构地区：[1]湖南省产商品评审中心,湖南长沙410004 [2]中南林业科技大学机电工程学院,湖南长沙410004

出　　处：《食品与机械》2023年第8期76-83,共8页Food and Machinery

基　　金：湖南省自然科学基金(编号:2020JJ4142);湖南省重点研发计划项目(编号:2018NK2066);湖南省教育厅科学研究重点项目(编号:20A515)。

摘　　要：目的:解决近红外光谱检测水果糖度固定光照角度获得光谱信息不够全面等问题。方法:基于光源远程运动中心简化模型,设计了一种漫透射近红外光谱检测柑橘糖度的光照角度可调装置,并对该装置进行了结构性能分析,开展了不同光照角度的柑橘糖度光谱检测试验。结果:该装置光照角度的调节范围可设置为0°~60°;60°时4个光源光斑中心与靶心位移偏差最小为7.5 mm;不同光照角度下2、3、4号光源光照角度平均值与1号光源基准值的误差在1°以下;光照角度30°时,原始透射率光谱数据所建的柑橘糖度预测模型效果最佳,预测集、校正集的相关系数和均方根误差分别为0.8876,0.8975和0.4560,0.4309°Brix。结论:所研制的近红外光谱检测装置能够实现自动同步调节4个光源对准水果中心的光照角度。Objective:To solve the problem of insufficient spectral information obtained by the fixed illumination angle of the near-infrared spectroscopy to detect the sugar content of fruits.Methods:A light angle adjustable device for the diffuse transmission near-infrared spectroscopy was designed to detect the sugar content of citrus based on the simplified model of the remote motion center of the light source.The device had carried out the structural performance analysis and the test of the citrus sugar under different illumination angles.Results:The adjustment range of the light angle of the device was set to 0°~60°.The displacement deviation between the center of the four light sources and the bullseye was the smallest(7.5 mm)at 60°.Under different illumination angles,the error between the average illumination angle of light source 2,3 and 4 and the reference value of light source 1 was within 1°.When the illumination angle was 30°,the citrus sugar prediction model based on the original transmittance spectrum data had the best effect.At this time,the correlation coefficient of the prediction set,the root mean square error of the prediction set,the correlation coefficient of the correction set,and the root mean square error of the correction set were 0.8876,0.8975,0.4560,0.4309°Brix,respectively.Conclusion:The developed near-infrared spectroscopy detection device can automatically synchronize and adjust the angle of illumination of four light sources to align with the center of the fruit.

关 键 词：近红外光谱 柑橘 糖度 光照角度 无损检测 

分 类 号：TS255.7[轻工技术与工程—农产品加工及贮藏工程] O657.33[轻工技术与工程—食品科学与工程]