Elemental profile and 207Pb/206Pb, 208Pb/206Pb, 204Pb/206Pb, 87Sr/86Sr isotope ratio as fingerprints for geographical traceability of Romanian wines

Abstract

Geographical wine traceability is an important topic in the context of wine authentification. Therefore, many researchers have addressed this subject by developing different methodologies based on multivariate analysis of organic and inorganic parameters and also by isotopic signature. The goal of this research was to assess the potential of elemental composition and isotopic signature of lead (207Pb/206Pb, 208Pb/206Pb and 204Pb/206Pb) and strontium (87Sr/86Sr) of wines from three Romanian vineyards, in order to highlight reliable markers for wine geographical origin. The ICP-MS method was used for the concentration determination for 30 elements (Ag, Al, As, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, In, K, Li, Mg, Mn, Na, Ni, Pb, Rb, Se, Sr, Tl, V, U, Zn, Hg). In this study 10 wines (2 red and 8 white) obtained from 'Merlot', 'Fetească neagră', 'Fetească albă', 'Fetească regală', 'Babeasca gri', 'Şarba', 'Aligoté', 'Sauvignon blanc', 'Muscat Ottonel', 'Italian Riesling' cultivars were investigated. The wine samples were obtained from micro-wine production under conditions of 2014, 2015, 2016 from Dealu Bujorului, Murfatlar and Ştefaneăti-Argeş vineyards. The high level of K (148.66±5.41-633.74±4.13 mg/L), Mg (88.23±0.84-131.66±3.42 mg/L), Ca (49.84±1.22-89.18±2.34) and Fe were observed in the wine samples analysed. Heavy metals like Hg, Pb, As and Cd (10.2-315 μg/L) were found below acceptable limits. Concentration of Na (1 mg/L), Cu (1 mg/L), As (0.2 mg/L), Cd (0.01 mg/L), Zn (5 mg/L) and Pb (0.15 mg/L) metals in analysed wine samples were under Maximum Permissible Limits (MPL), respectively as published by the Organization of Vine and Wine. The variation of the 207Pb/206Pb, 208Pb/206Pb, 204Pb/206Pb and 87Sr/86Sr ratio and K/Rb, Ca/Sr of the investigated wine clearly demonstrated that these variables are suitable traces for wine geographical origin determination. The proposed methodology allowed a 100% successful classification of wines according to the region of provenance.