Enological evaluation of the attitude of the grapevine fumin to give varietal wines

Abstract

Initiatives have been ongoing in recent years to safeguard biodiversity in the oenological sector via a process of enhancement of ancient varieties, under a pressure of a market strongly oriented towards production deriving from native vines of specific geographical zones. In that sense, Aosta Valley (Italy) has raised the need to preserve and characterize its minority vine varieties which have the potentiality to give varietal wines. Fumin represents the 7% of the production of the region with 16 hectares of vineyards and 753 hectolitres of derived wine. Due to its large phenolic potential, strong astringency and deep colour, it has long been, and is still today, assembled or blended with other varieties as occurs, for example, for the Torrette. It is the wine most produced in Aosta Valley and represents the 16% of the production. Previous studies carried out by our group highlighted for their oenological interest red Petit rou ge, Vuillermin, Cornalin, and Mayolet. The results outlined the needing of further researchers to evaluate the composition, behaviour and evolution of Fumin varietal wines. Body The aim of this work was to evaluate and compare the impact of three different types of winemaking of Fumin grapes in which the individual or combined effects of pre-fermentative and post-fermentative maceration, barrique and steel aging, malolactic fermentation and microoxygenation were tested. The sensory profiling of the wines obtained as well as the changes occurring in the chemical composition, colour parameters, polyphenol and aroma compounds, volatile phenols and biogenic amines were determined according to O.I.V. methods and metabolomic approaches thorough UPLC-MS. It was observed that pre-fermentative and post-fermentative maceration, as well as barrique and steel aging produced changes of the same magnitude in all the analyzed compounds. Sensory data also revealed that Fumin produced varietal wines with a great potential which would provide a viable alternative to some international red grape varieties and would favor the differentiation of the Aosta Valley on the national and international wine markets. In line with the new enological trends aimed at implementing the production of high-quality red wines from the exploitation of the intrinsic characteristics of the grapes and their preservation in the final product, the data provided by this study could be used as a chemotaxonomic tool to fingerprint Fumin for the first time.