What do metals tell us about wine?

The Influence of the Soil Profile on the Formation of the Elemental Image of Grapes and Wine of the Cabernet Sauvignon Variety

The features for assessing the authenticity of wines by region of origin are studied, based on the relationship between the mineral composition of the wine, the grapes, and the soil profile (0 to 160 cm) from the place of growth of Cabernet Sauvignon grapes. Soil, grape, and wine samples were taken from the territories of six vineyards in the Anapa district of Krasnodar Territory, Russia. Using the methods of ICP-OES, thermal, and X-ray phase analysis, the soils were differentiated into three groups, differing in mineralogical and mineral compositions. The soil samples of the first group contained up to 31% quartz, the second group up to 25% quartz and 19% mixed calcite, and the third group up to 32% calcite and 15% quartz. The formation of the elemental image of the grapes was studied, taking into account the total content and mobile forms of metals in the soil. The territorial proximity of the vineyards did not affect the extraction of elements from the soil into the grape berry, and the migration of metals for each territory was selective. According to the values of the biological absorption coefficient, the degree of transition of metals from the soil to a berry was estimated. For K, Ti, Zn, Rb, Cu, and Fe in all berries, the coefficient was higher than 1.00, which means that the berry extracts contained not only mobile-form, but also difficult-to-dissolve metal compounds. The migration of macro-components from the soil to the berry was low, and amounted to 6-7% for Ca, 0.8-3.0% for Na, and 25-70% for Mg of the concentration of their mobile forms. For all territories, the maximum correlation between metal concentrations in grapes and soil was observed for samples from a depth of 0-40 cm. The discriminant model based on concentrations of Rb, Al, K, Sr, Co, Na, Pb, Ca, and Ni showed the formation of clusters in the territories of vineyard cultivation. The developed model allow the problems of identifying wines by region to be solved with high accuracy, using their elemental image.

Authentication of selected white wines by geographical origin using ICP spectrometric and chemometric analysis

An important aspect of assessing the authenticity of wines is its geographical origin. The aim of the work is to authenticate by geographical origin according to the data of the ICP-spectrometric and chemometric analysis of elemental "images" of wines produced from white grape varieties Chardonnay, Riesling and Muscat grown in four regions of the Krasnodar Territory, Russia. The difference in the contents of Al, Ba, Ca and Rb in wines was found depending on the variety, and Al, Ba, Rb, Fe, Li, Sr - depending on the region of grape growth. Different models of the experimental data processing were used for attribution of the produced varieties of wine to the area of the grape's growth. The criterion for the quality of the constructed models was the accuracy of the attribution of a wine variety to the area of the grape's growth (%). Analysis of the elemental analysis data of 153 wine samples showed that in terms of attribution accuracy, automated neural networks (100 %) are preferred among machine learning methods, followed by support vector machines (98.69 %) and general discriminant analysis (94.77 %). The applied mathematical models enabled the revealing of the cluster structure of the analyzed wine varieties and their attribution to the area of a grape growth with high accuracy. Sr, Li and Fe concentrations in wines were found as the dominating predictors in the constructed models for definition of the geographical origin of wines. The combination of ICP-spectrometric analysis data with the capabilities of statistical modeling of machine learning methods focused on large-dimensional data made it possible to successfully solve small-dimensional problems of the definition of the geographical origin of wines by their elemental composition and variety.

Effects of geographical origin, vintage, and soil on stable isotopes and mineral elements in Ecolly grape berries for traceability

Stable isotopes and multi-element profiles of grapes and corresponding soils from different origins and vintages were determined by IRMS and ICP-MS, respectively. Stable isotope ratios and multi-element contents show significant differences among distinct regions and vintages. Grapes and soils were separated using δ2H and δ18O according to regions and vintages. PCA and CA results further verified that multi-element profiles were influenced by origins and vintages. In particular, δ2H, δ18O, and 21 elements in grapes were correlated with those in soil. Redundancy and Spearman analyses revealed that the BCF values were related to the longitude, latitude, altitude, precipitation, and average temperature. RF shows better performance than PLS-DA for discriminating grape origins and vintages. K, Tb, Cs, δ2H, and Co were important variables in discriminating grape origins. These findings confirm that isotopic and elemental profiles depend on the origin, vintage, and soil, establishing a promising method to discriminate grape origins and vintages.

Development of a green liquid-phase microextraction procedure using a customized device for the comprehensive determination of legacy and current pesticides in distinct types of wine samples

In this work, we reported the development of a novel, simple, and green liquid-phase microextraction (LPME) procedure based on the use of a customized device for the determination of 47 multiclass pesticides in red, white, and rosè wine samples by GC-MS. The main parameters that affect the LPME were optimized using multivariate statistical techniques such as centroid-simplex mixture design and Doehlert design. The optimal conditions were: 70 μL of toluene as extractor solvent; concentration of NaCl (2.7%, m v-1); pH 4; and an extraction time of 30 min, under vortex-assisted agitation (at 500 rpm). After validation, it was possible to obtain LOQ values as low as 7.63 ng L-1 and extraction recoveries ranging from 81.7% to 119% for most of the target pesticides. The application of exploratory analysis, specifically Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA), provided evidence indicating contamination in the different types of wine samples, primarily by systemic fungicides.

Elemental Profile and Health Risk of Fruška Gora Wines

The elemental composition of wine is influenced by endogenous sources and interventions from winemakers. The ICP-MS analysis of Fruška Gora wines (113) from vintages spanning across a decade (2011-2020), produced by 30 wineries and representing 18 autochthonous and international wine varieties, allowed a comprehensive insight into their elemental composition. Based on the mean concentrations of 23 investigated elements, B, Fe, and Mn, which were determined in mg per L of wine regardless of its colour or origin, were the most abundant. Red and white wines showed significant concentration differences in the case of B, Mn, and Sr (higher in red) as well as Be, Al, V, As, Mo, and Pb (higher in white). The elements of the highest toxicological concern were found in all (Pb and As) or almost all of the samples (Cd and Hg). Pb levels (maximum 47.1, 61.6, and 73.2 μg/L in red, rose, and white, respectively) were well below the legal limit. The applied risk assessment approaches (hazard quotient and index, margin of exposure) revealed no health concerns associated with consumption of Fruška Gora wines, except for a slightly increased lifetime cancer risk in the case of high wine consumption, and thus supported the promotion of Fruška Gora wines in the highly competitive international market.

Comparison and Intercorrelation of Various Bentonite Products for Oenological Properties, Elemental Compositions, Volatile Compounds and Organoleptic Attributes of White Wine

Bentonite fining is one of the generally applied wine-making technological elements that may seriously affect wine components. The aim of this study was (i) to investigate the effect of 21 bentonite products on eight oenological parameters, 19 elements, 21 volatile organic compounds (VOCs) and 10 organoleptic properties of white wine; and (ii) to quantify intercorrelations among the parameters separately for each of the four quality attributes. Among oenological parameters, sugar, acidity, malic-, lactic-, citric acid and total phenol contents were significant among several bentonite products. The amounts of elements were the lowest in the control wine treatments (with exceptions of, e.g., Ni and Cu); and these values were significantly different from several bentonite products. The relative presence of the VOCs was above 100% for most VOCs, but it was below 100% for 1-propanol, 4-amino-1,5-pentandioic acid and butane-dioic acid, and diethyl ester in all treatments. For organoleptic parameters, the values of clearness, colour, flavour intensity and taste persistency was the lowest in the control wine treatment, while the values of flavour character, flavour quality, taste intensity, taste character, and overall harmony were the highest for the bentonite products of AP, EBE, M-SA, EBE, EBE, respectively. Results of correlation and factor analyses showed strong intercorrelative effects of bentonite fining on the four quality attributes. In conclusion, this study can help in the proper choice of a specific bentonite product in relation to complexity effects of bentonite fining.

Distilled beverage aging: A review on aroma characteristics, maturation mechanisms, and artificial aging techniques

The market value of distilled beverage relies on its quality with a major contribution of distinctive and fascinating aromas. The aroma of distilled beverage is built on the basis of chemical components and can be modified through a series of physical and chemical processes such as aging. Revealing the hidden knowledge behind the evolution of numerous chemical components during these physicochemical processes in distilled beverages is not only significant but also challenging due to its complex system. In this review, the trends in the changes of associated aroma compounds over aging are proposed on the basis of understanding the relationship between chemical components and aroma profiles of numerous typical distilled beverages. The different aging systems, both classical platforms from Eastern countries (pottery jars) to Western countries (wood barrels), and modern platforms such as artificial aging technologies are outlined and compared with their respective applications. Optimizing aging processes is a challenging but imperative step, which warrants further fundamental knowledge from targeting aging-related molecules to the exploration of multitude physicochemical reaction mechanisms that occur during this process, such as the formation of potent odorant compounds in specific containers and environments, as well as mass transfer processes between solid and liquid interfaces. Understanding these maturation mechanisms of distilled beverages expressed by chemosensory signature holds promise for major improvements in future aging technologies that can efficiently yield stable and high-quality products.

Exploratory Analysis of South American Wines Using Artificial Intelligence

In this work, microwave-induced plasma optical emission spectrometry was applied for multielement determination in South American wine samples. The analytes were determined after acid digestion of 47 samples of Brazilian and Argentinian wines. Then, logistic regression, support vector machine, and decision tree for exploratory analysis and comparison of these algorithms in differentiating red wine samples by region of origin were carried out. All wine samples were classified according to their geographical origin. The quantification limits (mg L^-1) were P: 0.06, B: 0.08, K: 0.17, Mn: 0.002, Cr: 0.002, and Al: 0.02. The accuracy of the method was evaluated by analyzing the wine samples by ICP OES for results' comparison. The concentrations in mg L^-1 found for each element in wine samples were as follows: Al (< 0.02-1.82), Cr (0.15-0.50), Mn (< 0.002-0.8), P (97-277), B (1.7-11.6), Pb (< 0.06-0.3), Na (8.84-41.57), and K (604-1701), in mg L^-1.

Assessment of Physicochemical, Macro- and Microelements, Heavy Metals, and Related Human Health Risk from Organically, Conventionally, and Homemade Romanian Wines

From the consumers’ perspective, organic and homemade products have become more attractive than conventional ones. However, scientific data regarding the characteristics, properties, and composition of these products are scarce. This study assessed the elemental composition of organic, conventional, and homemade Romanian wines. The physicochemical composition, SO2 (free and total) and total concentration of macroelements, microelements, and heavy metals from nine wine regions containing 165 samples of white (38 organic/70 conventional/57 homemade), 67 red (22/31/14) and 7 rosé (2/2/3) wines were analyzed by inductively coupled plasma mass spectrometry. Dietary intake and target hazard quotient were also evaluated. The phytochemical and elemental compositions of the wine samples varied across regions and wine types. The highest levels of Ca, K, Fe and Al were detected in conventional wines, while homemade wines recorded high concentrations of Na, Mg, V, Ba and Rb. In the case of the rosé wine samples, the levels of trace elements and heavy metals were below the admissible limit. The estimated daily intake of a glass of wine provided less than 0.5% of the tolerable daily intake of the analyzed elements. No health concerns were identified. All wine samples can be safely consumed, regardless of the culture system used for production, and homemade wines are not of a lower quality than organic or conventional wines.

Application of benchtop total-reflection X-ray fluorescence spectrometry and chemometrics in classification of origin and type of Croatian wines

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A low-power benchtop TXRF system was used for analysis of 70 wine samples.

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The metal content of K, Ca, Fe, Cu, Zn, Mn, Sr, Rb, Ba, Pb, Ni, Cr and V was estimated by chemometric methods.

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Mn, K, Ni, Sr, Rb and Ba were the main variables used to differentiate by wine type and origin.

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LDA showed good detection and prediction abilities with selected elements.

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Classification of origin and type of Croatian wines by chemometric tools.

The contents of selected metals (K, Ca, Fe, Cu, Zn, Mn, Sr, Rb, Ba, Pb, Ni, Cr and V) in 70 wine samples from Continental and Adriatic part of Croatia and different types of wine (red and white) were determined by TXRF. The aim of this study was to compare the elemental composition of wines from two different regions and to determine the discriminant ability of each variable and to indicate which variables discriminate between the four categories considered.

Principal component analysis and cluster analysis showed that K, Mn, Ba and Ni can be considered as the most important characteristics to distinguish between Continental red and white wines, Rb, Ni and Ba for Continental red and Adriatic red wines while Sr is the only metal that completely distinguishes the samples of each category. Finally, linear discriminant analysis showed good recognition (100%) and prediction abilities (96.43%) using these selected elements.

Analysis of Selected Minerals in Homemade Grape Vinegars Obtained by Spontaneous Fermentation

Fruit vinegars are widely used as a spice and food preservative. They are considered as functional food, containing many bioactive compounds with pro-health benefits. Grape vinegars can be also a source of mineral compounds. Their quantity and diversity can be determined by environmental factors and growing conditions, such as temperature, mineral composition of the soil, heavy metal contamination, sunlight availability as well as grape variety and fruit ripeness stage. The aim of the study was to determine the content of minerals in homemade grape vinegars, obtained by spontaneous fermentation. Five different grape (Vitis vinifera L.) varieties were used in the study (Cabernet Cortis, Johanniter, Solaris, Souvignier gris and Prior). Moreover, the effect of sugar addition in the fermentation process on the mineral content was examined. The mineral content was determined using the ICP-OES method. Among the analysed samples, potassium was the most abundant element (936.07-1472.3 mg/L of vinegar). Comparative analysis showed that the content of Ca, Fe and Cr was significantly higher in vinegars prepared from red varieties than in white-coloured ones. In turn, vinegars prepared from white grape varieties contained statistically significantly higher content of potassium. Vinegar colour did not have a significant influence on the content of the remaining elements included in the analysis. Furthermore, statistical analysis did not reveal any significant differences in the content of the analysed minerals in any of the grape varieties used between the samples with and without sugar addition.

From Soil to Grape and Wine: Geographical Variations in Elemental Profiles in Different Chinese Regions

Elemental profiles are frequently applied to identify the geographical origin and authenticity of food products, to guarantee quality. The concentrations of fifteen major, minor, and trace elements (Na, Mg, K, Ca, Al, Fe, Mn, Cu, Zn, Rb, Sr, Li, Cd, Cs, and Ba) were determined in soils, “Meili” grapes, and wines from six regions in China by inductively coupled plasma mass spectrometry (ICP-MS). The elemental concentrations in these samples, according to the geographical origins, were analyzed by one-way analysis of variance (ANOVA) with Duncan’s multiple comparisons. The bioconcentration factor (BCF) from soil to grape and the transfer factor (TF) from grape to wine were calculated. Mg, K, Ca, Cu, Zn, Rb, Sr, and Ba presented higher BCF values than the other seven elements. The TF values of six elements (Na, Mg, K, Zn, Li, and Cs) were found to be greater than one. Moreover, the correlation of element content between the pairs of soil–grape, grape–wine, and bioconcentration factor (BCF)–environmental factor were analyzed. Significant correspondences among soil, grape, and wine were observed for K and Li. Two elements (Sr and Li) showed significant correlations between BCF and environmental factor (relative humidity, temperature, and latitude). A linear discriminant analysis (LDA) with three variables (K, Sr, Li) revealed a high accuracy (>90%) to determine the geographical origin for different Chinese regions.

Elemental composition, rare earths and minority elements in organic and conventional wines from volcanic areas: The Canary Islands (Spain)

The organic wine market is rapidly growing worldwide, both in terms of production and consumption. However, the scientific literature is not conclusive regarding differences in the elemental composition of wines according to their production method, including both major and trace elements. Minerals can be present in wine as a result of both anthropogenic and environmental factors. To date, this has not been evaluated in volcanic contexts, neither has the emergent issue of rare earths and other minority elements as potential sources of food contamination. This study using inductively coupled plasma mass spectrometry (ICP-MS) analyses organic and conventional wines produced in the Canary Islands (Spain), an archipelago of volcanic origin, to compare their content of 49 elements, including rare earths and minority elements. Our results showed that organic wines presented lower potential toxic element content on average than their conventional counterparts, but differences were not significant. Geographical origin of the wine samples (island) was the only significant variable differentiating wine samples by their composition profiles. By comparing our data with the literature, no agreement was found in terms of differences between organic and conventionally-produced wines. This confirms that other factors prevail over elemental composition when considering differences between wine production methods. Regarding the toxicological profile of the wines, five samples (three organic and two conventional) exceeded the maximum limits established by international legislation. This highlights the need for stricter analytical monitoring in the Canary Islands, with a particular focus on Cu and Ni concentration, and potentially in other volcanic areas.

Plant uptake and soil retention of radionuclides and metals in vineyard environments

In most European countries, each adult citizen drinks on average more than 20 L of wine every year. Three popular wine-growing areas (Aleksandrovac, Topola, and Orahovac) in Serbia were studied in order to investigate the abundance and uptake of elements from vineyard soil to plants. The specific activities of radionuclides (²²⁶Ra, ²³²Th, ⁴⁰K, ¹³⁷Cs, and ⁷Be) were measured in soil, leaves, and grape berries. ²²⁶Ra and ²³²Th were positively correlated with silt and clay and negatively correlated with sand content in soil. Specific activities of natural radionuclides were also negatively correlated with soil pH and CaCO₃. Significant correlations of ⁴⁰K and ¹³⁷Cs with organic matter in soil were found. Concentrations of fifteen metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, Fe, K, Na, Ca, Mg, and Hg) were also measured in soil samples as well as in grapevine leaves. Analyzed soils were rich in Ni, Cu, Co, Cr, and Cd. High concentrations of Cu were probably caused by long-term use of Cu-based fungicides. Cu was correlated with Fe and organic matter content in soil. Soil-to-plant transfer factors (TF) were calculated to estimate the uptake of radionuclides and metals. Correlations obtained via PCA enable distinction between the sites Aleksandrovac and Topola relative to Orahovac. The first principal component (PC1) accounting for 30.70% of the total variance correlated significantly with soil pH (H₂O), contents of CaCO₃, Na, Ca, ⁴⁰K, and ²²⁶Ra in soil, as well as with ²²⁶Ra, Na, Ca in plants and TF_Ca. The second principal component (PC2), with total variance of 17.21%, was mainly correlated with variables pertaining to Mg, Co, and Cr in the soil and TF_K.

Ethnic food beverages with heavy metal contents: Parameters for associated risk to human health, North-East India

Food beverage consumption is a worldwide age-old practice. It is also a common run-through habit among the tribes of North Eastern parts of India. The food beverage group Jou is a traditionally fermented rice-based beverage by Bodo community of Assam, the largest plain tribe. It is not only consumed by Bodos on regular basis but also widely used in their socio-cultural activities. Joubidwi (JB, fermented product), Joufinai (JF, preserved product) and Jougwran (JG, distilled) are the three varieties of Jou. Herewith, it had been reported; the concentrations of metals such as Cd, Co, Cr, Cu, Fe, K, Mn, Na, Ni, Pb and Zn in the three varieties of Jou to make people aware about the possible health benefits as well as the risks associated with the consumption of Jou. The metal contents were estimated using ICP-OES after digesting the samples with 10:1 mixture of concentrated nitric and concentrated sulfuric acid. The estimated daily intakes (EDI) of metals from consumption of JB, JF and JG were also within the recommended daily allowances (RDA). From the estimated target hazard quotient (THQ) values, it was observed no health risk associated with the consumption of Jou; whereas total target hazard quotient (TTHQ) of Joufinai were associated with more health risks. Metal concentrations of all metals in Bodo beverages was lower in comparison with barely based and wheat based beverages.

A fast, low-cost, sensitive, selective, and non-laborious method based on functionalized magnetic nanoparticles, magnetic solid-phase extraction, and fluorescent carbon dots for the fluorimetric determination of copper in wines without prior sample treatment

A new fluorimetric method for copper(II) determination in wines was developed combining functionalized magnetic nanoparticles (FMNP) and fluorescent carbon dots (FCD). To produce FMNP, Fe₃O₄ was coated with Al₂O₃ forming Fe₃O₄@Al₂O₃ core-shell magnetic nanoparticles and functionalized with PAN and SDS. FCD was synthesized from pineapple juice through hydrothermal carbonization. For copper determination, aliquots of wine, the FMNP dispersion, and Britton-Robinson buffer (pH = 4.0) were mixed under stirring to allow the adsorption of copper by FMNP. Cu-FMNP complex was attracted by a niobium magnet and, after discarding the non-magnetic material, the copper(II) ions were eluted with an FCD dispersion before fluorescence quenching measurements. The proposed method presented a linear range from 0.020 to 0.100 mg L^-1 (r² = 0.9953), RSD (intraday) < 3.0%, and recovery rates from 96 to 105 %. FMNP and FCD properties permitted extraction/preconcentration/determination of copper within 1 min with an enrichment factor of nine and without prior sample treatment.

Influence of food matrix and food processing on the chemical interaction and bioaccessibility of dietary phytochemicals: A review

Consumption of phytochemicals-rich foods shows the health effect on some chronic diseases. However, the bioaccessibility of these phytochemicals is extremely low, and they are often consumed in the diet along with the food matrix. The food matrix can be described as a complex assembly of various physical and chemical interactions that take place between the compounds present in the food. Some studies indicated that the physiological response and the health benefits of phytochemicals are resultant in these interactions. Some food substrates inhibit the absorption of phytochemicals via this interaction. Moreover, processing technologies have been developed to facilitate the release and/or to increase the accessibility of phytochemicals in plants or breakdown of the food matrix. Food processing processes may disrupt the activity of phytochemicals or reduce bioaccessibility. Enhancement of functional and sensorial attributes of phytochemicals in the daily diet may be achieved by modifying the food matrix and food processing in appropriate ways. Therefore, this review concisely elaborated on the mechanism and the influence of food matrix in different parts of the digestive tract in the human body, the chemical interaction between phytochemicals and other compounds in a food matrix, and the various food processing technologies on the bioaccessibility and chemical interaction of dietary phytochemicals. Moreover, the enhancing of phytochemical bioaccessibility through food matrix design and the positive/negative of food processing for dietary phytochemicals was also discussed in this study.

Reproducibility of elemental profile across two vintages in Pinot noir wines from fourteen different vineyard sites

The reproducibility of elemental profile in wines produced across vintages of 2015 and 2016 has been studied using grapes from a single scion clone of Vitis vinifera L. cv. Pinot noir. Grapevines were grown on fourteen different vineyard sites, from Oregon to southern California in the U.S.A., which span distances from approximately hundreds of meters to 1450 km, while elevations range from near sea level to nearly 500 m. The number of elements quantified in the wines made from the 2016 vintage was thirty, by using inductively coupled plasma mass spectrometry (ICP-MS). These data were compared with the twenty-seven elements quantified and previously reported in wines made from 2015 vintage, including twenty-four elements reported in both vintages. The composition of each element was analyzed by analysis of variance with main effect of vineyard. Wines were classified according to vineyard origin and environmental growing site with a combination of factors correlated with the wine elemental profile. The low variability (< 25%) of certain elements in wines from at least eight sites across both vintages, including Group 1 (Cs, K, Na and Rb), Group 2 (Ba, Ca, Mg and Sr), Group 3B (Eu), Group 13 (Al, B and Ga), Group 15 (As and P) and Co, Fe, Mn, Ni and V, demonstrated the reproducibility over the seasons analyzed (2015 and 2016). The comparison of elemental profile of wines across growing seasons demonstrates the opportunity to reproduce one key aspect of wine chemistry across vintages.

Heavy metal and essential elements in beers from turkey market: A risk assessment study

In this study, the level of arsenic (As), lead (Pb) and cadmium (Cd) and also essential elements in beer samples consumed in Turkey were investigated using the inductively coupled plasma mass spectrometry (ICP-MS) method. The heavy metal-induced non-carcinogenic and carcinogenic risks were calculated. For essential elements, the calculated estimated daily intake of iron (Fe), copper (Cu), selenium (Se) and cobalt (Co) from beer consumption were compared with their toxicity reference values. Tukey post-hoc test showed that As was found at a significantly higher level when compared to Pb. Also, a significant correlation was found between As level and alcohol by volume percent. All samples had a hazard quotient and hazard index <1, indicating no non-carcinogenic risk from exposure to single or multiple heavy metals. Some samples exceeded the threshold limit of acceptable cancer risk for As in the high beer consumer group. This assessment showed that in addition to health implications based on the alcohol content of beer, there might be a carcinogenic risk associated with the heavy metals content of these beverages.

Elemental Analysis and Phenolic Profiles of Selected Italian Wines

The study of the chemical composition of wines is nowadays a topic of great interest because of the importance of this market, especially in Italy, and also considering the numerous cases of falsification of famous and very expensive wines. The present paper focused on the analysis of metals and polyphenols in Italian wines belonging to different provenance and types. At this purpose 20 elements were quantified by inductively coupled plasma optical emission spectrometry (ICP-OES) and ICP mass spectrometry (ICP-MS). Regarding polyphenols, a total of 32 were quantified, among 6 were anthocyanins. Furthermore, in 4 samples (1 rosè and 3 red wines) 42 anthocyanins and related compounds were identified by ultra-high performance liquid chromatography (UHPLC)-Orbitrap MS technique (among these, 6 were also quantified). Non-anthocyanins were determined using UHPLC coupled with a diode array detector and triple-quadrupole mass spectrometer (UHPLC-DAD-QqQ-MS). Total phenolic content (TPC) and radical scavenging activity (RSA) were measured using spectrophotometric methods. The results obtained by elemental techniques were submitted to principal components analysis (PCA) allowing to get information on both geographical and botanical origin of the examined wine samples. Some polyphenols have been detected in higher concentrations only in a certain type of wine, as for example in the case of Grechetto wine. Most of the identified anthocyanin derivatives (pyranoanthocyanins) are formed during the aging of wine by reaction with the other wine components.

Multi-Elemental Analysis of Wine Samples in Relation to Their Type, Origin, and Grape Variety

Wine is one of the most popular alcoholic beverages. Therefore, the control of the elemental composition is necessary throughout the entire production process from the grapes to the final product. The content of some elements in wine is very important from the organoleptic and nutritional points of view. Nowadays, wine studies have also been undertaken in order to perform wine categorization and/or to verify the authenticity of products. The main objective of this research was to evaluate the influence of the chosen factors (type of wine, producer, origin) on the levels of 28 elements in 180 wine samples. The concentration of studied elements was determined by ICP-MS (Ag, B, Ba, Be, Bi, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Rb, Sb, Sn, Sr, Te, Tl, U, Zn), ICP-OES (Ca, Fe, K, Mg, Ti), and CVAAS (Hg) techniques in 79 red, 75 white, and 26 rose wine samples. In general, red wines contained higher values of mean and median of B, Ba, Cr, Cu, Mn, Sr and Zn in contrast to other wine types (white and rose). In white wines (when compared to red and rose wines) higher levels of elements such as Ag, Be, Bi, Cd, Co, Li, K and Ti were determined. In contrast, rose wines were characterized by a higher concentration of Fe and U. The study also revealed that in the case of 18 samples, the maximum levels of some metals (Cd—8 samples, Pb—9 samples, Cu—1 sample) were slightly exceeded according to the OIV standards, while for Zn and Ti in any wine sample the measured concentrations of these metals were above the permissible levels. Thus, it can be stated that the studied wines contained, in general, lower levels of heavy metals, suggesting that they should have no effect on the safety of consumption. The results also showed higher pH level for red wines as a consequence of the second fermentation process which is typically carried out for this type of wine (malolactic fermentation). The highest median value of pH was reported for Merlot-based wines, while the lowest was for Riesling. It is assumed that dry Riesling has a higher content of tartaric and malic acid than dry Chardonnay grown in the same climate. From all of the studied countries, wines from Poland seemed to present one of the most characteristic elemental fingerprints since for many elements relatively low levels were recorded. Moreover, this study revealed that also wine samples from USA and Australia can be potentially discriminated from the rest of studied wines. For USA the most characteristic metal for positive identification of the country of origin seems to be uranium, whereases for Australia – strontium and manganese. Based on the highly reduced set of samples, it was not possible to differentiate the studied wine products according to the grape variety other than Syrah, and partially Chardonnay. Since all the Syrah-based samples originated from the same country (Australia) thus, the observed grouping should be more related with the country of origin than the grape variety.

Prospect on Rare Earth Elements and Metals Fingerprint for the Geographical Discrimination of Commercial Spanish Wines

This paper presents a novel tool for Spanish commercial wine discrimination according to their designation of origin (PDO). A total of 65 commercial wines from different Spanish designation of origin (Alicante, Bullas, Campo de Borja, Jumilla, Castilla la Mancha, Ribeiro, Ribera de Duero, Rioja, Rueda, Utiel-Requena, Valdepeñas and Valencia) were characterized. The rare earth elements (REEs) content was determined by a high-temperature torch integrated sample introduction system (hTISIS) coupled to inductively coupled plasma mass spectrometry (ICP-MS). The REE content was used to draw characteristic PDOs radar charts. Results indicated that the REEs fingerprint provides a good prospect to discriminate the different Spanish PDOs, except for Alicante, Castilla la Mancha, Jumilla, Utiel-Requena and Valdepeñas. Finally, for those PDOs that were not properly distinguished, a second fingerprint obtained from Ba, Co, Cr, Mn, Ni, Pb and V content was used for discrimination purposes.

Preliminary Study of Microelements, Phenolics as well as Antioxidant Activity in Local, Homemade Wines from North-East Greece

The present study is aimed to analyze the composition of microelements in wines prepared by amateur winemakers in Drama region (recognized as Protected Geographical Indication (PGI)), especially the toxic ones, as well as the phenolic content and antioxidant activity of these wines since moderate wine consumption may contribute to health benefits to the consumers. A total of twenty-four wines, comprising sixteen red and eight white, were tested. The micro and macroelements were determined with ICP-OES (Inductively coupled plasma-optical emission spectrometry). Chromatic characteristics of wines and total phenolic and flavonoid compounds as well as their antioxidant activity with three different assays were determined spectrophotometrically. The amateur’s wines showed levels of contaminants with toxic metals less than the limits set from the International Organization of Vine and Wine (OIV). Moreover, toxic metals concentrations were comparable to those of European wines. The Principal Component Analysis discriminated wines into white and red and further distinguished the red wine into two groups depending on the Total Flavonoid content, antioxidant activity and color intensity. The moderate consumption of amateur wines can be recommended since their consumption is not harmful to the health, and they contain high amount of phenolics and flavonoids comparable or even higher to that of commercial wines.

Authentication and Traceability Study on Barbera d’Asti and Nizza DOCG Wines: The Role of Trace- and Ultra-Trace Elements

Barbera d’Asti—including Barbera d’Asti superiore—and Nizza are two DOCG (Denominazione di Origine Controllata e Garantita) wines produced in Piemonte (Italy) from the Barbera grape variety. Differences among them arise in the production specifications in terms of purity, ageing, and zone of production, in particular with concern to Nizza, which follows the most stringent rules, sells at three times the average price, and is considered to have the highest market value. To guarantee producers and consumers, authentication methods must be developed in order to distinguish among the different wines. As the production zones totally overlap, it is important to verify whether the distinction is possible or not according to metals content, or whether chemical markers more linked to winemaking are needed. In this work, Inductively Coupled Plasma (ICP) elemental analysis and multivariate data analysis are used to study the authentication and traceability of samples from the three designations of 2015 vintage. The results show that, as far as elemental distribution in wine is concerned, work in the cellar, rather than geographic provenance, is crucial for the possibility of distinction.

Vineyard site impact on the elemental composition of Pinot noir wines

Elemental composition was used to characterize and differentiate 14 wines made from the identical clone of Vitis vinifera cv. Pinot noir (clone 667). The vineyards span distances which range from several hundred meters to 1540 km and their elevations vary from near sea level to nearly 500 m. Twenty-seven elements were observed above the limit of quantitation by using inductively coupled plasma mass spectrometry (ICP-MS) in the wines from at least half of the 14 sites. Concentrations of several elements, including Mo, Er, Na, Li, Cs and Pb, varied by 10-fold across the 14 wines. Multiple factor analysis (MFA) of elemental composition with juice chemistry and site characterization show associations consistent with expectations, such as high Ca with high clay content. These results demonstrate that even when grapevine clone and winemaking protocol are controlled, composition differences in wines produced from sites are mediated by diverse soil and microclimate conditions.

Evolution of the Multielemental Content along the Red Wine Production Process from Tempranillo and Grenache Grape Varieties

In the present work, 38 elements were quantified in the different fractions generated by applying amateur winemaking methods. Inductively Coupled Plasma Mass Spectrometry was used as detection technique. Grapes were analyzed and separate metal profiles were also obtained for the skin and seeds. Additional vinification fractions included musts before and after the fermentation process. Meanwhile, solid fractions corresponded to the so-called hat, pressed pomace and the lees obtained after gravitational settling at the tank bottom. Wine was further analyzed. The obtained results revealed a different repartition depending on the particular element and winemaking solid and liquid fraction evaluated. The studies included vinification in presence and in absence of added yeast and grape geographical origin. Principal component analysis helped to discriminate among fractions and to determine the critical elements behaving differently. Finally, a mass balance allowed to unequivocally detect the migration of a given element to the winemaking fractions.

Multivariate optimization of an analytical method for the analysis of Abruzzo white wines by ICP OES

An inductively coupled plasma-optical emission spectrometry (ICP OES) method was optimized and applied for determining the concentration of 14 elements (Ba, Ca, Co, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Sr, V, and Zn) in three representative white wines of the Abruzzo region (Italy). In order to optimise an ICP OES method a three level factorial design for three variables was used. The intensity of the emission lines for analytes was simultaneously maximised by using Derringer's desirability function. Using this approach, the optimal experimental conditions for wine analysis of 0.48 L min-1, 1.8 mL min-1 and 0.5 L min-1 for the nebulizer gas flow rate, sample uptake rate and auxiliary gas flow rate respectively were achieved. A total of 46 white wine samples of the three varieties were analysed by using the optimised experimental conditions. Linear Discriminant Analysis (LDA) and Partial Least Squares Linear Discriminant Analysis (PLS LDA) allowed an acceptable classification of the three varietal samples.

The Use of Macro, Micro, and Trace Elemental Profiles to Differentiate Commercial Single Vineyard Pinot noir Wines at a Sub-Regional Level

The compositional authentication of wine is of great interest, as the geographic origin of the grapes is often associated with quality, uniqueness, and authenticity. Previous elemental fingerprinting studies mainly discriminated wines from different countries or regions within a country. Here, we report the use of element profiles to distinguish commercial Pinot noir wines from five sub-regional appellations or neighborhoods within one American viticultural area (AVA). Fifty-three single cultivar wines were collected over two harvests and analyzed using microwave plasma-atomic emission spectroscopy (MP-AES) and inductively coupled plasma-mass spectrometry (ICP-MS). Of 62 monitored elements that were quantified with fully validated methods, 24 and 32 elements differed significantly across the neighborhoods and vintages, respectively (p < 0.05). Targeted canonical variate analysis (CVA) explained 85–90% of the variance ratio across the two vintages, indicating persistent and stable elemental fingerprints of wines at a sub-regional level. A sixth, newly founded neighborhood was correctly grouped separately from the others using a Soft Independent Modeling of Class Analogy (SIMCA), indicating the potential of elemental fingerprints for wine authenticity.

Variation in the mineral composition of wine produced using different winemaking techniques

It has been reported that the concentrations of minerals in wines can be used to discriminate their geographical origin. However, some winemaking techniques may also affect the mineral concentration of the final product. In this study, we examined the effects of various winemaking techniques, including (i) fining, (ii) aging with oak tips, (iii) maceration with grape skins, (iv) chaptalization and acidification, and (v) yeast nutrient addition for alcohol fermentation, on the concentration of 18 minerals (Li, B, Na, Mg, Si, P, S, K, Ca, Mn, Co, Ni, Ga, Rb, Sr, Mo, Ba and Pb) in a total of 154 wine samples using grapes from different production areas. Among the various winemaking techniques, maceration with grape skin had the largest effect on mineral content, significantly changing the concentrations of 17 or 18 elements (B, Na, Mg, Si, P, S, K, Ca, Mn, Co, Ni, Ga, Rb, Sr, Mo, Ba and Pb). Fining treatment using bentonites had the second largest effect, altering the concentrations of 14 elements (Li, B, Na, Si, P, S, Ca, Co, Ga, Rb, Sr, Mo, Ba and Pb). However, in principal component analysis using all data (n = 154), the wine samples were clearly clustered according to grapes used in the experiments rather than the winemaking technique. In conclusion, some winemaking techniques significantly altered the concentration of some minerals in wine; however, the principal factor influencing wine mineral composition seems to be its geographical origin.

Effects of metals released in strong-flavor baijiu on the evolution of aroma compounds during storage

Storage is essential in improving the quality of strong-flavor baijiu (SFB). Here, we investigated the release behaviors of metals from containers into SFB and their effects on the evolution of aroma compounds during storage. Twenty-six metals were identified in SFB samples. The concentrations of Na, K, Ca, Mg, Al, and Fe obviously increased after storing in pottery jar, whereas those of Fe and Cu greatly increased after storing in stainless-steel vessel. The volatility of most esters, alcohols, ketone, furan, and aldehyde decreased, whereas that of most acids increased after adding the metal ions into fresh SFB. The fluorescence intensity of SFB decreased with increased aging time in pottery jar, whereas the fluorescence intensity of acids was quenched with adding Fe3+ and Cu2+. All these results suggested that some metals released from containers had binding affinities with acids, thereby reducing SFB organoleptic stimulation by forming metal-aroma compound complexes during storage.

Tin and mercury and their speciation (organotin compounds and methylmercury) in worldwide red wine samples determined by ICP-MS and GC-ICP-MS

One hundred and twenty-two red wines were analysed for their total tin, total mercury and speciation concentrations. Total Sn and Hg concentrations were in average 4.4 ± 7.2 µg/L and 0.22 ± 0.12 µg/L, respectively. Two GC-ICP-MS methods were developed and validated for speciation purposes: one to measure organotin compounds (OTCs) with internal standard correction; the other, to evaluate methylmercury (MeHg⁺) by isotopic dilution. Methyltins (mainly dimethyltin, but also monomethyltin) were the most abundant OTCs recovered. Methylation seems to occur biotically during the wine making process and not during the bottling time. Therefore, it also seems to be roughly dependent on the geographical origin of the wine. For higher OTCs, monobutyltin was the most regularly found, but dibutyltin and monooctyltin were also detected sometimes. MeHg⁺ was not recovered in any of the samples investigated, probably due to the low level of Hg. These results suggest that, in terms of these parameters, normal consumption of wine is not a hazard for human health.

Quantification of manganous ions in wine by NMR relaxometry

Proton relaxation in model and real wines is investigated for the first time by fast field cycling NMR relaxometry. The relaxation mechanism unambiguously originates form proton interaction with paramagnetic ions naturally present in wines. Profiles of a white Chardonnay wine from Burgundy, a red Medoc, and model wines are well reproduced by Solomon-Bloembergen-Morgan equations. Relaxation is primarily governed by interactions with Mn²⁺. A straightforward model-independent quantification of the manganese ion concentration (down to few tens of μg/L) is proposed.

An Approach of the Madeira Wine Chemistry

Madeira wine is a fortified Portuguese wine, which has a crucial impact on the Madeira Island economy. The particular properties of Madeira wine result from the unique and specific winemaking and ageing processes that promote the occurrence of chemical reactions among acids, sugars, alcohols, and polyphenols, which are important to the extraordinary quality of the wine. These chemical reactions contribute to the appearance of novel compounds and/or the transformation of others, consequently promoting changes in qualitative and quantitative volatile and non-volatile composition. The current review comprises an overview of Madeira wines related to volatile (e.g., terpenes, norisoprenoids, alcohols, esters, fatty acids) and non-volatile composition (e.g., polyphenols, organic acids, amino acids, biogenic amines, and metals). Moreover, types of aroma compounds, the contribution of volatile organic compounds (VOCs) to the overall Madeira wine aroma, the change of their content during the ageing process, as well as the establishment of the potential ageing markers will also be reviewed. The viability of several analytical methods (e.g., gas chromatography-mass spectrometry (GC-MS), two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC-ToFMS)) combined with chemometrics tools (e.g., partial least squares regression (PLS-R), partial least squares discriminant analysis (PLS-DA) was investigated to establish potential ageing markers to guarantee the Madeira wine authenticity. Acetals, furanic compounds, and lactones are the chemical families most commonly related with the ageing process.

Using neural networks to identify the regional and varietal origin of Cabernet and Merlot dry red wines produced in Krasnodar region

This paper shows a possibility of establishing the authenticity and geographic origin of wines by neural networks based on multi-element analysis. The study used 144 samples of Cabernet and Merlot dry red wines pro- duced in Krasnodar Region according to traditional technologies. The wines were provided by the producers or pur- chased in retail stores. The concentrations of 20 micro- and macroelements in red wines were determined by atomic emission spectroscopy with inductively coupled plasma. The analysis of average elemental contents showed a signi- ficant dependence of wine composition on the grape variety and place of origin, which enabled us to examine inter- relations between the elements and think of a way to identify them by means of classification models. The software STATISTICA Neural Networks was used to assess a possibility of determining the grape variety and geographical origin. The neural networks constructed in the study contained five variables corresponding to the elements with sta- tistically significant correlations between the names of the regions and the wine samples, namely Fe, Mg, Rb, Ti, and Na. These predictors were able to determine the grape variety and place of growth with a sufficiently high accuracy. In the test sample set, the accuracy reached 95.24% and 100% for variety and region identification, respectively. A software product was developed to automate the calculations based on the neural networks. The program can estab- lish the grape variety from a minimal set of microelements, and then, based on the variety and the same set of micro- elements, determine its place of origin.

Mineral composition of organic and conventional white wines from Italy

Despite of the increased interest of consumers for organic agro-food products and of the growing demand for organic wines, scientific literature reports a limited number of studies aimed to evaluate the chemical composition of organic wine with respect to conventional wine in terms of major and trace metals. In the present study the concentrations of 19 elements (Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Sr, V, and Zn) were determined in samples of white wines from Italy, conventionally and organically produced. No significant difference in the mineral composition was found between the two groups, except for Ni, which showed a higher concentration in organic wines. By comparing our data with data from literature it can be pointed out that there is no agreement among the results presented in the different studies referring to comparisons between organically and conventionally produced wines, concluding that the mineral composition of wines depends on factors different from organic/conventional production method.