Abstract：
Stable isotope ratios and trace elements are well-established tools that act as signatures of the product\'s environmental conditions and agricultural processes; but they involve time, money, and environmentally destructive chemicals. In this study, we tested for the first time the potential of near-infrared reflectance spectroscopy (NIR) to estimate/predict isotope and elemental compositions for the origin verification of coffee. Green coffee samples from two continents, 4 countries, and 10 regions were analysed for five isotope ratios (δ13C, δ15N, δ18O, δ2H, and δ34S) and 41 trace elements. NIR (1100-2400 nm) calibrations were developed using pre-processing with extended multiplicative scatter correction (EMSC) and mean centering and partial-least squares regression (PLS-R). Five elements (Mn, Mo, Rb, B, La) and three isotope ratios (δ13C, δ18O, δ2H) were moderately to well predicted by NIR (R2: 0.69 to 0.93). NIR indirectly measured these parameters by association with organic compounds in coffee. These parameters were related to altitude, temperature and rainfall differences across countries and regions and were previously found to be origin discriminators for coffee.
摘要：
稳定的同位素比率和微量元素是完善的工具，作为产品的环境条件和农业过程的特征;但它们涉及时间，钱，和环境破坏性化学品。在这项研究中,我们首次测试了近红外反射光谱（NIR）估计/预测同位素和元素组成的潜力，用于咖啡的来源验证。来自两大洲的绿咖啡样本，4个国家,并分析了10个区域的5个同位素比率(δ13C，δ15N,δ18O,δ2H,和δ34S）和41种微量元素。NIR（1100-2400nm）校准是使用具有扩展乘法散射校正（EMSC）和均值居中和偏最小二乘回归（PLS-R）的预处理开发的。五种元素（Mn，Mo,Rb,B,La）和三个同位素比率（δ13C，δ18O,δ2H）通过NIR（R2：0.69至0.93）中度到很好地预测。NIR通过与咖啡中的有机化合物结合来间接测量这些参数。这些参数与海拔高度有关,不同国家和地区的温度和降雨差异，以前被发现是咖啡的原产地鉴别器。
