Specificity and Origin of the Stability of the Sr Isotopic Ratio in Champagne Wines

Robin Cellier,Ekaterina Epova,Patrick Ors,Anne-Laure Ronzani,Julien Barre,Stanislas Milcent,Olivier F X Donard,Cornelis Van Leeuwen,Sylvain Bérail

doi:10.3390/molecules26165104

Abstract

The 87Sr/86Sr ratio of 39 Champagnes from six different brands, originating from the whole “Appellation d’Origine Contrôlée” (AOC) Champagne was analyzed to establish a possible relation with the geographical origin. Musts (i.e., grape juice) and base wines were also analyzed to study the evolution of the Sr isotopic ratio during the elaboration process of sparkling wine. The results demonstrate that there is a very homogeneous Sr isotopic ratio (87Sr/86Sr = 0.70812, n = 37) and a narrow span of variability (2σ = 0.00007, n = 37). Moreover, the Sr concentrations in Champagnes have also low variability, which can be in part explained by the homogeneity of the bedrock in the AOC Champagne. Measurements of the 87Sr/86Sr ratio from musts and base wines show that blending during Champagne production plays a major role in the limited variability observed. Further, the 87Sr/86Sr of the musts were closely linked to the 87Sr/86Sr ratio of the vineyard soil. It appears that the 87Sr/86Sr of the product does not change during the elaboration process, but its variability decreases throughout the process due to blending. Both the homogeneity of the soil composition in the Champagne AOC and the blending process during the wine making process with several blending steps at different stages account for the unique and stable Sr isotopic signature of the Champagne wines.

Highlights

The geographical origin of food products has become an increasingly important issue for consumers, producers and distributors
The Sr isotopic ratios of 39 Champagnes from six different brands were determined by MC-ICP-MS
Since there is no blending at all during the different steps of the wine making process for these single vineyard Champagnes, and that we have previously demonstrated in this paper that the grape varieties have no influence on the Sr isotopic signature, these slight but significant differences of Sr isotopic signature most likely originate from the soil composition

Summary

Introduction

The geographical origin of food products has become an increasingly important issue for consumers, producers and distributors. The wine composition is influenced by many factors such as soil, climate, grapevine variety, training system, vineyard floor management and other parameters linked to oenological practices and the use of additives [1,2] In this context, for all wines, and here for sparkling wines, the Sr isotopic ratios can be considered as an important variable that will trace the “terroir” and the environment of the wine. During the uptake of Sr and the metabolism pathway of the plant, the Sr isotopic ratio is unaffected so its signature is extremely conservative [5] It remains generally unchanged throughout the process from grapes to wine [12,13]

Methods

Results

Conclusion