Elemental profile and oxygen isotope ratio ( δ 18 O) for verifying the geographical origin of Chinese wines

Abstract

The elemental profile and oxygen isotope ratio (δO) of 188 wine samples collected from the Changji, Mile, and Changli regions in China were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma optical emission spectroscopy (ICP-OES) and isotope ratio mass spectrometry (IRMS), respectively. By combining the data of δO and the concentration data of 52 elements, the analysis of variance (ANOVA) technique was firstly applied to obtain the important descriptors for the discrimination of the three geographical origins. Ca, Al, Mg, B, Fe, K, Rb, Mn, Na, P, Co, Ga, As, Sr, and δO were identified as the key explanatory factors. In the second step, the key elements were employed as input variables for the subsequent partial least squares discrimination analysis (PLS-DA) and support vector machine (SVM) analyses. Then, cross validation and random data splitting (training set: test set = 70:30, %) were performed to avoid the over-fitting problem. The average correct classification rates of the PLS-DA and SVM models for the training set were both 98%, while for the test set, these values were 95%, 97%, respectively. Thus, it was suggested that the combination of oxygen isotope ratio (δO) and elemental profile with multi-step multivariate analysis is a promising approach for the verification of the considered three geographical origins of Chinese wines.

Geographic classification of U.S. Washington State wines using elemental and water isotope composition

“…In the LDA, δD is identified as the 6th discriminator. Other studies that use δ 18 O and elemental analyses found that δ 18 O contributes significantly to regional discrimination in wines from Brazil, Romania, China and Italy (Dinca et al, 2016, Dutra et al, 2011, Fan et al, 2018, Raco et al, 2015). It was unclear, however, if δD was measured in these studies.

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“…Note that a maximum of 6 comparison pairs are possible for the 4 regions. In many studies world-wide, Mn and Rb have proven to be important independent classifiers (Durdic et al, 2017, Fan et al, 2018, Pepi and Vaccaro, 2018, Taylor et al, 2003). In the present study, only Mn is used in LDA, where it appears as the first classifier, separating CA from SA (Table 2).…”

“…Sr is another important classifier found to discriminate between wines world-wide, here it is the 11th component in the LDA, separating EU and SA (Table 2, Fig. S2) (Coetzee et al, 2014, Fan et al, 2018, Pepi and Vaccaro, 2018, Versari et al, 2014). Sr correlates with As, Na, and B in PC6 (4.7% variance).…”

“…By using C and O stable isotope ratios and concentrations of 10 trace metals, 90.4% classification of the Romanian wines and verification of vintage year were achieved. In a recent study carried out on Chinese wines, δ 18 O also played a significant role in discriminating between wines from different regions (Fan et al, 2018). The European Union implemented stable isotope applications in official food analyses in 1990, including the isotope ratios of H, C, and O of water and ethanol within wines.…”

Разработка Системы Показателей Качества И Технологических Свойств В Цепочке «виноград - Сусло - Виноматериал - Вино», Дифференцирующей Вина Крыма По Географическому Происхождению

“…В качестве идентифицирующих критериев предлагаются показатели, как непосредственно связанные с качественными характеристиками винопродукции (в частности, компоненты углеводно-кислотного [1,2], фенольного [3,4], ароматобразующего [5,6] комплексов), так и показатели, взаимосвяь которых с качеством продукции весьма опосредована или не доказана (аминокислотный, катионно-анионный состав, редкоземельные и микроэлементы [7][8][9][10], соотношениz изотопов 87 Sr/ 86 Sr, 13 с/ 12 с, 18 о/ 16 о [11][12][13] и др. Чаще всего современнные подходы к идентификации происхождения вин базируются на измерении системы показателей [14][15][16].…”