Characterizing wine terroir using strontium isotope ratios: a review

This paper presents a detailed review of the use of Sr-87/Sr-86 isotope systematics for wine provenance studies. The method is based on the principle that the Sr isotope ratio in wine reflects that of the labile fraction of the vineyard soil from which the wine is produced. The review encompasses Sr-87/Sr-86 data from wine samples published between 1993 and 2021 from terroirs in 22 different countries. The analytical procedures and techniques adopted by the different authors and the range of isotope ratios obtained in the different studies are discussed and evaluated. This study provides a bibliometric analysis of the Sr-87/Sr-86 isotope approach for wine authentication at different scales. Although limitations are evident when implemented at large (global) scales, we demonstrate that the Sr-87/Sr-86 isotope tracing technique remains a powerful and reliable tool for determining the geographical origin of wine when combined with detailed knowledge of the geological and soil characteristics of the substrata. For example, this combination of data allows the wines grown in the volcanic soils of Central and Southern Italy to be unambiguously fingerprinted. We present a detailed protocol for the application of the Sr isotope technique to wine authentication.