Department of Analytical Chemistry, Faculty of Science and Technology, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, 48080 Bilbao, Spain.
Talanta. 2012 Jan 15;88:303-10. doi: 10.1016/j.talanta.2011.10.045. Epub 2011 Oct 31.
The feasibility of using Fourier Transform Mid-Infrared Spectroscopy (FT-MIR) combined with Partial Least Squares Regression (PLS-R) for the determination of 12 anthocyanins (3-O-glucosides of delphinidin, cyanidin, petunidin, peonidin and malvidin, as well as acetic acid esters and p-coumaric acid esters of petunidin, peonidin and malvidin and caffeic acid ester of malvidin) and three sums (sum of non-acylated anthocyanins, sum of acetylated anthocyanins and sum of coumaroylated anthocyanins), in red wines has been tested. Reference values of anthocyanin concentrations by reverse-phase High Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD) were used to calibrate the models. A Principal Component Analysis (PCA) was applied to these reference values and a differentiation of wine samples by wine type (young wines of 2005, young wines of 2004 and crianza and reserva wines) has been possible. A calibration model using PLS-R was built with 153 samples of Rioja wines and the prediction of the anthocyanin concentrations using this model was evaluated by internal and external validation sample sets. Most of the anthocyanins and their sums have been predicted with a Standard Error of Prediction (SEP) of 15-30% for young wines recently bottled. However, for young wines after one year of being bottled, and for crianza and reserva wines, these errors were unacceptable. The obtained results suggest that the model built for FT-IR instrument calibration is a useful tool for a quick determination of the anthocyanin content of young wines of the current vintage, but a careful robust external validated calibration of the technique is necessary in order to maintain the prediction errors within controlled limits.
使用傅里叶变换中红外光谱（FT-MIR）结合偏最小二乘回归（PLS-R）测定 12 种花色苷（矢车菊素、飞燕草素、锦葵素、芍药素的 3-O-葡萄糖苷，以及矢车菊素、芍药素和锦葵素的乙酸酯和对香豆酸酯，以及锦葵素的咖啡酸酯）和三种总和（酰化花色苷的总和、乙酰化花色苷的总和和香豆酰化花色苷的总和）的可行性已在红葡萄酒中进行了测试。反相高效液相色谱-二极管阵列检测（HPLC-DAD）的花色苷浓度参考值用于校准模型。对这些参考值进行主成分分析（PCA），并通过葡萄酒类型（2005 年轻葡萄酒、2004 年轻葡萄酒和陈酿葡萄酒和珍藏葡萄酒）对葡萄酒样品进行了区分。使用 PLS-R 建立了一个校准模型，其中包含 153 个里奥哈葡萄酒样本，使用该模型预测花色苷浓度的内部和外部验证样本集进行了评估。对于最近装瓶的年轻葡萄酒，大多数花色苷及其总和的预测标准误差（SEP）为 15-30%。然而，对于装瓶一年后的年轻葡萄酒和陈酿葡萄酒和珍藏葡萄酒，这些误差是不可接受的。结果表明，为 FT-IR 仪器校准建立的模型是快速测定当前年份年轻葡萄酒花色苷含量的有用工具，但需要对该技术进行仔细的稳健外部验证校准，以将预测误差控制在可接受范围内。
