Geographical Discrimination of Croatian Wines by Stable Isotope Ratios and Multielemental Composition Analysis

Renata Leder; Ivana Vladimira Petric; Josipa Jusup; Mara Banović

doi:10.3389/fnut.2021.625613

Geographical Discrimination of Croatian Wines by Stable Isotope Ratios and Multielemental Composition Analysis

Front Nutr. 2021 Mar 4:8:625613. doi: 10.3389/fnut.2021.625613. eCollection 2021.

Authors

Renata Leder¹, Ivana Vladimira Petric², Josipa Jusup³, Mara Banović⁴

Affiliations

¹ Department of Physico-Chemical Testing, Center for Viticulture, Enology and Edible Oils Analysis, Croatian Agency for Agriculture and Food, Zagreb, Croatia.
² Department for Authentic Products, Center for Viticulture, Enology and Edible Oils Analysis, Croatian Agency for Agriculture and Food, Zagreb, Croatia.
³ Primevigilance d.o.o., Zagreb, Croatia.
⁴ Department of Food Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Zagreb, Croatia.

Abstract

The δ¹⁸O and δ¹³C (analyzed by isotope ratio mass spectrometry, IRMS) and concentration of 22 selected elements (analyzed by inductively coupled plasma-optical emission spectrometry, ICP-OES) in 190 Croatian microvinified and commercial wine samples from continental and coastal winegrowing areas and from three viticultural zones (B, CI, and CII) were measured to investigate whether multivariate statistical methods could provide the fingerprint for geographical origin determination. The highest power for discrimination of wines produced in Croatian winegrowing areas was achieved by general discriminant analysis (GDA) showing correct classification of 97.9% of all investigated samples, 100.0% of microvinified samples and 84.8% of commercial samples in the cross-validation matrix. The most significant markers for discrimination of coastal and continental areas found by GDA were δ¹⁸O and Co, followed by K, Rb, Sn, Li, and δ¹³C in descending order. GDA showed higher levels of correctly classified samples from three viticultural zones in Croatia if only microvinified samples were employed in the analysis (94.9%) than for all samples together (86.3%) or for commercial samples (66.1%) in the cross-validation matrix. The discrimination of viticultural zones B, CI, and CII in Croatia was achieved by δ¹⁸O, Co, Rb, Li, K, and Sn. The results obtained showed that the relationships between the isotopic ratios and concentrations of different considered elements combined with appropriate statistical model represent a powerful tool in discrimination of wines produced in different Croatian winegrowing areas.

Keywords: Croatian wines fingerprint; elements; geographical origin; inductively coupled plasma optical emission spectroscopy; isotope ratio mass spectrometry; stable isotopes.