Investigation of heavy metal concentrations in some Turkish wines

Characterization of Semisweet and Sweet Wines from Kos Island Produced Traditionally and Conventionally

Eight wines, four semisweet rosé and four sweet red, produced on Kos Island in Greece, were analyzed. Wines produced following different winemaking procedures were characterized based on their physicochemical parameters, total phenolic content, antioxidant activity, and chromatic properties. Moreover, their elemental composition was studied with ICP-OES. Differences were observed among the measurements performed. All of the samples were below the levels set for SO2 content. The sweet red wines had higher alcoholic strength than semisweet rosé ones, and were characterized by a higher yellow proportion. The vinification process significantly affected SO2 levels, phenolics, and antioxidant activity. The red wines were high in Na content, with one sample exceeding the level set by OIV (International Organization of Vine and Wine). The levels of all the other elements related to quality (Fe, Cu, Zn) or safety (Pb, Cd) were far below the limits set. Rosé wines contained less Mg, but were higher in Na than the red ones. The obtained data suggest that sweet and semisweet wines produced with traditional procedures are safe and of high quality, holding antioxidant capacity beneficial to health. The information reported contributes to a better understanding of these types of wines.

Determination of Metal Content by Inductively Coupled Plasma-Mass Spectrometry in Polish Red and White Wine Samples in Relation to Their Type, Origin, Grape Variety and Health Risk Assessment

The main objective of the research was to assess the influence of selected factors (type of wine, grape variety, origin, alcohol content and daily consumption) on the concentration levels of 26 elements in 53 Polish wine samples, also using chemometric analysis tools. Concentration of Al, As, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Ni, Pb, Sb, Se, Sr, Ti, V, Zn and Zr was analyzed by ICP-MS, while concentration of Ca, Na, K and Mg was determined by ICP-OES. White wines were characterized by higher concentrations of Al, As, Be, Ca, Co, Cu, Fe, Hg, Li, Mg, Na, Pb, Sb, Ti, V, Zn and Zr (mean values: 0.075-86,403 μg·L-1 in white wines, 0.069-81,232 μg·L-1 in red wines). Red wines were characterized by higher concentrations of Ba, Cd, Cr, K, Mn, Se and Sr (mean values: 0.407-1,160,000 μg·L-1 in white wines, 0.448-1,521,363 μg·L-1 in red wines). The results obtained for the health risk assessment indices, including the Target Hazard Quotient (THQ, mean values per glass of wine: 2.097 × 10-5 (Cr)-0.041 (B) in all wines), indicate that the analyzed elements do not show a potential toxic effect resulting from wine consumption. The chemometric analysis confirmed that elements such as Li, Ti, Ca, Mn, Sr, Ba, Zn, Mg, Cu, Se and B were closely related to local conditions and soil properties, and the presence of Fe, Cr, V and Pb was related to contamination of the soil.

Democratization of Copper Analysis in Grape Must Following a Polymer-Based Lab-on-a-Chip Approach

Quality control in the food industry is of the upmost importance from the food safety, organoleptic and commercial viewpoints. Accordingly, the development of in situ, rapid, and costless analytical tools is a valuable task in which we are working. Regarding this point, the copper content of grape must has to be determined by wineries along the wine production process. For this purpose, grape must samples are sent to laboratories where the copper content is measured usually by flame atomic absorption spectrometry or by inductively coupled plasma mass spectrometry. We herein propose a straightforward, rapid, and inexpensive methodology based both on a film-shaped colorimetric polymer sensor and a smartphone method that at the same time can be used by unskilled personnel. The sensory polymer films change their color upon dipping them on the grape must, and the color evolution is analyzed using the digital color parameters of a picture taken to the film with a smartphone. Furthermore, the analytical procedure is automatically carried out by a smartphone app. The limit of detection of copper of the polymer sensor is 0.08 ppm. Following this approach, 18 production samples coming from the French Groupe ICV company were studied. The copper content of the samples was analyzed by the usual procedure carried out by the company (flame atomic absorption spectrometry) and by the method proposed in this work, ranging this content from 0.41 to 6.08 ppm. The statistical study showed that the results of both methods are fully consistent, showing the validity of the proposed method for the determination of copper in grape must within the frame of wine production wineries and industries.

Copper in grape and wine industry: Source, presence, impacts on production and human health, and removal methods

Heavy metals are of particular concern in grape and wine processing, especially copper. The sources of copper are diverse, including vineyard soil, copper-containing pesticides on the fruit surface, copper wine-making equipment, and exogenous addition in winemaking. Copper has potential risks to human nerves, metabolism, and others. It can inhibit yeast growth, delay fermentation, and also mediate oxidation reactions, which has a huge impact on the nutritional quality and sensory quality of fresh wine and aged wine. It is therefore crucial to detect, quantify, and remove copper from grapes and wine. However, the copper situations in the wine industries of various countries are complicated and diverse, and the existing forms of copper are quite different, which makes the research challenging. This review summarizes and analyzes the existence and influence of copper in the wine industry by analyzing the sources of, the current situation regarding, and the detection and removal methods for copper in wine. With the study, a better understanding of copper's impact on wine production will be gained, facilitating further control of copper in wine and helping the wine industry grow.

Multivariate Statistical Analysis for Mutual Dependence Assessment of Selected Polyphenols, Organic Acids and Metals in Cool-Climate Wines

Polyphenols, organic acids and metal ions are an important group of compounds that affect the human health and quality of food and beverage products, including wines. It is known that a specific correlation between these groups exist. While wines coming from the New World and the Old World countries are extensively studied, wines coming from cool-climate countries are rarely discussed in the literature. One of the goals of this study was to determine the elemental composition of the wine samples, which later on, together as polyphenols and organic acids content, was used as input data for chemometric analysis. The multivariate statistical approach was applied in order to find specific correlations between the selected group of compounds in the cool-climate wines and the features that distinguish the most and differ between red and white wines and rosé wines. Moreover, special attention was paid to resveratrol and its correlation with selected wine constituents.

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.

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.

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.

Voltammetric Determination of Lead and Copper in Wine by Modified Glassy Carbon Electrode

This paper describes the determination of Pb and Cu with a Nafion-modified glassy carbon electrode and MnCo₂O₄ nanoparticles as working electrode for anodic stripping voltammetry. Pb and Cu were accumulated in HCl/KCl (0.1 mol dm^-3) at a potential of -1.4 V (vs. Ag/AgCl electrode) for 480 s, followed by a linear sweep anodic stripping voltammetry (ASV) scan from -1.0 to +0.5 V. Under optimum conditions, the calibration curves were linear in the range of 0.01 - 8 and 0.01 - 5 mg dm^-3 for Pb and Cu, respectively. Effect of sample dilution, accumulation time and potential were optimized. A study of interfering substances was performed. A significant increase in current was obtained at the modified electrode in comparison with the bare glassy carbon electrode. The modified electrode was successfully applied for determination of Pb and Cu in wine samples after a simple preparation procedure. Pb and Cu content in wine was used for estimation of the target hazard quotient (THQ) values for minimal and maximal levels of the metals.

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.

Mineral Composition Evaluation in Energy Drinks Using ICP OES and Chemometric Tools

This study reports the simultaneous determination of the total concentrations of Al, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, and Zn in 17  samples of commercial energy drinks through inductively coupled plasma optical emission spectrometry and multivariate methods, such as Pearson correlation and principal component analysis (PCA), in order to conduct a more thorough evaluation of the original data. The samples studied were stored in two types of containers (polyethylene terephthalate bottles and aluminum cans) and purchased in the city of Belém (State of Pará, Brazil). The results showed high Na content in energy drinks, followed by K, Ca, and Mg. The accuracy of the optimized method was evaluated with the certified reference materials to assess trace elements in water (NIST 1643e); the resultant recoveries varied from 83 to 105%. Energy drinks stored in cans presented higher levels of aluminum and magnesium, while those bottled in polyethylene terephthalate bottles had a higher K content. There were significant differences between the observed Na concentrations and the values dictated on the drink package. Furthermore, PCA explained 70.38% of the total variance, allowing for an evaluation of the degree of similarity between the energy drinks studied and showing that the main contributions to the formation of groups are related to Fe, Na, Mg, and Zn contents. These results will be used to better understand the distribution of inorganic elements contained in energy drinks.

A Human Health Risk Assessment of Trace Elements Present in Chinese Wine

The concentrations of trace elements in wines and health risk assessment via wine consumption were investigated in 315 wines. Samples were collected from eight major wine-producing regions in China. The concentrations of twelve trace elements were determined by inductively coupled plasma mass spectrometry (ICP-MS) and Duncan's multiple range test was applied to analyze significant variations (p < 0.05) of trace elements in different regions. Based on a 60 kg adult drinker consuming 200 mL of wine per day, the estimated daily intake (EDI) of each element from wines was far below the provisional tolerable daily intake (PTDI). Health risk assessment indicated the ingestion influence of individual elements and combined elements through this Chinese wine daily intake did not constitute a health hazard to people. However, Cr and Mn were the potential contaminants of higher health risk in Chinese wines. The cumulative impact of wine consumption on trace elements intake in the daily diet of drinkers should not be ignored due to the presence of other intake pathways.

Quantification of toxic metals during different winemaking stages

Heavy metals in beverages can constitute serious problems to human health. Consumption of wine may contribute to the daily dietary intake of pollutants, especially of toxic (heavy) metals. These compounds are also known as priority pollutants due to their potential toxic effects, if concentrations are not kept under allowable limits. Many characteristics such as: quality, origin, aroma and health safety of wine are influenced by environmental and anthropogenic factors. Hence, the contamination of wine by priority pollutants may occur at different stages of vine-growing, due to the application of agricultural chemicals, or at different stage of winemaking and ageing, because of the extended contact of wine with winemaking equipment materials (aluminium, brass, glass, stainless steel and wood, etc.), or chemicals used for cleaning and sanitation. The aim of this study is to identify and quantify the heavy metal ions from red wines. A particular focus was attributed to Zn and Cd from destemming-pressing-filtration-bottling stages in Fetească neagră grape variety from Cotnari vine growing region of Romania. Results indicated that heavy metals were linked to diverse Zn and Cd sources and complexes during the winemaking processes. Concentration of Zn and Cd were generally higher in must than in wine, although heavy metals concentrations were lower than the limits recommended by the International Organization of Vine and Wine for human health safety.

Analytical features of microwave plasma-atomic emission spectrometry (MP-AES) for the quantitation of manganese (Mn) in wild grape (Vitis coignetiae) red wines: Comparison with inductively coupled plasma-optical emission spectrometry (ICP-OES)

The analytical features of MP-AES for the determination of Mn in wine were studied as compared with ICP-OES. The optimum spectral line (403.076 nm) of MP-AES was different from that (259.373 nm) of ICP-OES. Significant matrix effect was observed with MP-AES, but not with ICP-OES. A simple and cost-effective MP-AES for the quantitation of Mn in wild grape (Vitis coignetiae) red wines were developed and validated. A standard addition method was used to compensate the matrix effects. The sensitivity of MP-AES was comparable to that of ICP-OES. MP-AES was sensitive, precise, accurate and reliable. The Mn concentration in the wild grape wines was in the range of 502-3627 μg L^-1. MP-AES had a distinct drawback of low matrix tolerance. However, MP-AES had a clear advantage of the low running cost due to the use of nitrogen gas generated from air with a nitrogen generator.

Differences in the levels of pesticides, metals, sulphites and ochratoxin A between organically and conventionally produced wines

Organic products are generally recognized to be healthier and safer than conventional products. However, the actual scientific data regarding the importance of organic production on particular contaminant/additive content of wines is scarce. This study aimed to evaluate contents of pesticides, metals, sulphites and ochratoxin A in organically (org) and conventionally (conv) produced wines from eleven locations in different winegrowing regions of Croatia. All wines contained significantly lower levels of residues as compared to the maximum limits (MLs) with the exception of excessive amounts of Cu and Zn in one sample. Pb and Mg were mainly significantly less represented in org wines. There were no significant differences in the content of sulphite or ochratoxin A between org and conv wines. Significantly lower total pesticide concentrations and average number of pesticides per sample were obtained in org wines. The majority of ochratoxin A positive wines were from conv wine producers.

Determination of Selected Metals in Fruit Wines by Spectroscopic Techniques

BACKGROUND

The determination of metals in different types of food and beverages samples has drawn significant attention due to several reasons with the most important one being the nutritional and toxic effects of these elements or their compounds. The knowledge of certain elements content in wines/fruit wines is of special interest due to their toxicity in case of excessive intake and also the effect they seem to have on the organoleptic properties of wine.

RESULTS

The study was focused on measuring the concentration levels of trace metals in fruit wines. Analysis of K, Ca, Fe, Zn, Cd, Mg, Pb, Sn, and Hg in so-called homemade fruit wine was carried out by AES, AAS, CV-AAS, and GF-AAS techniques. The calculated calibration curves showed good linearity range for all tested analytes (with coefficient of determination in the range from 0.989 to 0.999). The low values of the limit of detection (from 0.0031 μg/L to 0.47 mg/L) and the limit of quantification (from 0.009 μg/L to 1.41 mg/L) were obtained.

CONCLUSIONS

The allowed levels of metal in fruit wines are prescribed by the International Office for Grapes and Wines (OIV). The data obtained from the study area for all metals did not exceed the international limits.

Elemental composition as a tool for the assessment of type, seasonal variability, and geographical origin of wine and its contribution to daily elemental intake

This study was designed to fill a gap, about Serbian wines, analysing 63 wines produced in 4 different regions in Serbia.

Blackberry wines mineral and heavy metal content determination after dry ashing: multivariate data analysis as a tool for fruit wine quality control

This study brings out the data on the content of 21 mineral and heavy metal in 15 blackberry wines made of conventionally and organically grown blackberries. The objective of this study was to classify the blackberry wine samples based on their mineral composition and the applied cultivation method of the starting raw material by using chemometric analysis. The metal content of Croatian blackberry wine samples was determined by AAS after dry ashing. The comparison between an organic and conventional group of investigated blackberry wines showed statistically significant difference in concentrations of Si and Li, where the organic group contained higher concentrations of these compounds. According to multivariate data analysis, the model based on the original metal content data set finally included seven original variables (K, Fe, Mn, Cu, Ba, Cd and Cr) and gave a satisfactory separation of two applied cultivation methods of the starting raw material.