Multivariate analysis of FTIR and ion chromatographic data for the quality control of tequila
Multivariate analysis of FTIR and ion chromatographic data for the quality control of tequila
复制标题
DOI：
10.1021/jf048637f
复制
发表时间：
2005-03-23
影响因子：
6.1
通讯作者：
Schreier, P
中科院分区：
文献类型：
--
作者：
Lachenmeier, DW;Richling, E;Schreier, P
主成分分析（PCA）被施加到正宗的墨西哥龙舌兰酒（n = 14）和市售样品在墨西哥和德国（n = 24）的色谱和光谱数据。占变异性78%的氯离子、硝酸根、硫酸根、乙酸根和草酸根阴离子的前两个主成分（PC）的分数散点图允许对墨西哥和海外瓶装的龙舌兰酒进行分类;然而，龙舌兰酒类别之间不可能存在歧视。墨西哥产品的无机阴离子浓度（范围= 1.5-5.1 mg/L;平均值= 2.5 mg/L）显著（p = 0.0014）低于进口国瓶装产品（范围= 3.3-62.6 mg/L;平均值= 26.3 mg/L）。FTIR允许使用偏最小二乘回归快速筛选密度和乙醇以及挥发性化合物甲醇、乙酸乙酯、丙醇-1、异丁醇和2-/3-甲基-1-丁醇（精密度= 5.3- 29.3%）。使用挥发性化合物的PCA，来自“100%龙舌兰”（龙舌兰韦伯变种）的龙舌兰之间的区别。阿苏尔，龙舌兰科）和龙舌兰酒与其他发酵糖（“混合”龙舌兰酒）是可能的。前两个PC描述了数据总变异性的89%。甲醇和异丁醇影响PC 1的变异性，从而导致歧视。甲醇和异丁醇的浓度显著高于（甲醇，p = 0.004;异丁醇，p = 0.005）（甲醇，297.9 +/- 49.5;异丁醇，251.3 +/- 34.9）比混合龙舌兰酒（甲醇，197.8 +/- 118.5;异丁醇，151.4 +/- 52.8）。
Principal component analysis (PCA) was applied to the chromatographic and spectroscopic data of authentic Mexican tequilas (n = 14) and commercially available samples purchased in Mexico and Germany (n = 24). The scores scatter plot of the first two principal components (PC) of the anions chloride, nitrate, sulfate, acetate, and oxalate accounting for 78 % of the variability allowed a classification between tequilas bottled in Mexico and overseas; however, no discrimination between tequila categories was possible. Mexican products had a significantly (p = 0.0014) lower inorganic anion concentration (range = 1.5-5.1 mg/L; mean = 2.5 mg/L) than the products bottled in the importing countries (range = 3.3-62.6 mg/L; mean = 26.3 mg/L). FTIR allowed a rapid screening of density and ethanol as well as the volatile compounds methanol, ethyl acetate, propanol-1, isobutanol, and 2-/3-methyl-1-butanol using partial least-squares regression (precisions = 5.3-29.3 %). Using PCA of the volatile compounds, a differentiation between tequila derived from "100 % agave" (Agave tequilana Weber var. azul, Agavaceae) and tequila produced with other fermentable sugars ("mixed" tequila) was possible. The first two PCs describe 89 % of the total variability of the data. Methanol and isobutanol influenced the variability in PC1, which led to discrimination. The concentrations of methanol and isobutanol were significantly higher (methanol, p = 0.004; isobutanol, p = 0.005) in the 100 % agave (methanol, 297.9 +/- 49.5; isobutanol, 251.3 +/- 34.9) than in the mixed tequilas (methanol, 197.8 +/- 118.5; isobutanol, 151.4 +/- 52.8).