近红外光谱结合不同偏最小二乘法快速检测镇江香醋的浑浊度

利用近红外光谱(4000cm-1～10000cm-1)结合化学计量学方法快速检测了镇江香醋中的浑浊度。首先,用近红外光谱仪采集香醋样本的近红外光谱数据以及用离心法测定样本的浑浊度值;然后,采用间隔偏最小二乘法(iPLS)、反向区间偏最小二乘法(biPLS)、联合间隔偏最小二乘算法(siPLS)优选光谱特征区间;最后,采用全光谱(4000cm-1～10000cm-1)偏最小二乘法(PLS)对优选出来的区间建立香醋浑浊度近红外光谱模型。结果表明,采用siPLS将全光谱均匀划分30个子区间,选择4个子区间4 10 18 27]联合时,建立的模型预测效果最佳,其RMSECV和RMSEP分别为0.173和0.208,校正集和预测集相关系数分别为0.9337和0.9004。因此,利用近红外光谱技术快速检测香醋中的浑浊度是可行的。

Determination of turbidity of Zhenjiang fragrance vinegar based on NIR combined with different PLS methods

Near infrared spectroscopy（4000cm-1～10000cm-1） combined with chemometrics methods was applied for turbidity determination of Zhenjiang fragrance vinegar.Firstly,data of fragrance vinegar were collected using near infrared reflectance spectroscopy（NIRS） equipment and the turbidity of samples were got by centrifugation;secondly,three improved partial least squares（PLS） methods,including interval partial least squares（iPLS）,backward interval partial least squares（biPLS） and synergy interval partial least squares（siPLS）,were used to find the most informative ranges;lastly,models with better predictive turbidity of fragrance vinegar using PLS was established in the whole wavelength range 4000cm-1～10000cm-1.The results showed that the models by siPLS method,which separated the whole spectra into 30 intervals,and combine four intervals of 4 10 18 27] had the best predictive ability,the RMSECV and RMSEP were 0.173 and 0.208,respectively,and the calibration and prediction correlation coefficient were 0.9337 and 0.9004.Using NIRS for rapid detection of turbidity of fragrance vinegar was feasible.