FTIR/ATR光谱应用于甘蔗糖蜜锤度的快速测定

采用FTIR/ATR光谱,偏最小二乘法(PLS)和Savitzky-Golay(SG)平滑方法建立甘蔗糖蜜锤度的快速测定方法和光谱分析的优化模型。基于全谱4500—600cm-1,利用计算机算法平台,把483种SG平滑模式和1—40的PLS因子数任意组合分别建立PLS模型。根据预测效果,最优模型为原谱平滑,2、3次多项式类型,45平滑点数,PLS因子数为6,预测均方根偏差(RMSEP)、预测相关系数(rp)和相对预测均方根偏差(RRMSEP)分别为0.978%、0.902%和1.05%,预测精度很高,并且大幅度优于未做SG平滑处理直接用PLS建模的预测效果。从而表明,FTIR/ATR光谱能够应用于甘蔗糖蜜锤度的快速准确测定,SG平滑模式和PLS因子数的联合大范围筛选能够有效地应用于FTIR/ATR光谱分析的模型优选。

Rapid Determination of Sugarcane Molasses Brix by the Application of FTIR/ATR Spectroscopy

Sugarcane molasses brix was determined fast by FTIR/ATR spectroscopy with partial least squares (PLS) and Savitzky-Golay (SG) smoothing method,and the optimal spectral analysis model was also established.The PLS model was established by any combination of 483 SG smoothing models and 1-40 PLS factors, based on the whole region (4500-600cm~(-1)) and the computer algorithm platform.According to the prediction effect, the optimal model is the original spectra smoothing, 2 or 3 degree polynomial, 45 smoothing points, the PLS factor of 6,and RMSEP, r_p and RRMSEP of 0.978 %, 0.902 and 1.05 % respectively.The prediction accuracy is very high,and it is substantially superior to the prediction effect of the PLS model without SG smoothing.The results show that FTIR/ATR spectroscopy can be used to the rapidly accurate determination of sugarcane molasses brix, and large-scale optimization combining SG smoothing modes and PLS factors can be effectively applied to the model optimization of FTIR/ATR spectral analysis.