摘要
基于漫反射法的番石榴可溶性固形物含量(SSC)无损检测中,确定番石榴最佳光谱取样的位置和数量,对提高检测精度具有重要意义。分别采集番石榴顶端、赤道和底部区域漫反射光谱,每个区域采集4处,以赤道1处、赤道4处平均和全部12处平均光谱作为各样本的光谱,建立PLS模型并对独立预测集样本进行预测。结果显示,12处平均光谱数据建模效果最好,其预测相关系数Rp=0.962,预测均方根误差RMSEP=0.432;赤道4处平均光谱建模效果次之,Rp=0.793,RMSEP为0.588;赤道1处光谱建模效果最差,Rp=0.687,RMSEP=0.599。再经过连续投影算法(SPA)筛选全谱变量,得到23个特征波长,此时PLS模型的Rp=0.902,RMSEP=0.438。试验结果表明,番石榴多处平均的漫反射光谱充分携带其内在品质信息,建模效果优于单处或单区域采样光谱。
It is important to select optimum spectra sampling position and quantity in noninvasive examination of guava based on near-infrared diffuse reflection. Firstly, 12 kinds of spectra were collected from top, equator and bottom, respectively, then models were built based on 1 spectrum in equator, average spectrum of 4 spectra in equator and average spectrum of 12 spectra all over the samples. The prediction results demonstrated that the model based on average spectrum of 12 spectra all over the samples was the best, with Rp=0.962, RMSEP=0.432; the model based on average spectrum of 4 spectra in equator was better, with Rp=0.793, RMSEP=0.588; the model based on 1 spectrum in equator was the worst, with Rp=0.687, RMSEP=0.438. At last, 23 wavelengths were derived through successive projections algorithm. The model based on the 23 wavelengths produced Rp=0.902, RMSEP=0.438. As a result, the average transmission spectra all over top, equator and bottom contain the sample internal quality information adequately. The model based on the all over average spectrum had better result than the models based on single point or average spectrum over single district.
出处
《广东农业科学》
CAS
CSCD
北大核心
2014年第6期205-208,共4页
Guangdong Agricultural Sciences
基金
广东省教育厅高校优秀青年创新人才培养计划(2012LYM_0028)
教育部高等学校博士学科点专项科研基金(20124404120006)
国家自然科学基金青年基金(31201129)
关键词
番石榴
可溶性固形物
漫反射
光谱取样位置
近红外光谱
guava
soluble solid content
diffuse reflection
spectrum sampling position
near-infrared spectra
