Vitamins in musts : an unexplored field

Abstract

Vitamins are major compounds, involved in several prime yeast metabolic pathways. Yet, their significance in oenology has remained mostly unexplored for several decades and our current knowledge on the matter still remaining obscure to this day. While the vitaminic contents of grape musts have been approached in these ancient investigations, their vitameric composition have never even been investigated so far. To shed light onto this unexplored field, a novel HPLC procedure has been developed and validated for the simultaneous and direct analysis of 19 different vitamers from 8 different vitaminic groups (B1, B2, B3, B5, B6, B8, B9, C) in a one-hour chromatography run, that is exempted from any treatment of the sample prior to injection. This technique has allowed for the characterization of 85 white grape musts from different geographical origins, cultivars, as well as vintages. Noticeable patterns appeared in regard to the grapevines areas of cultivation, suggesting possible leads for further characterization. Overall, vitamins stand as highly diverse and versatile in concentrations, strongly varying between musts. This analytical tool could allow to further define the yeast nutritional requirements for vitamins, and, as such, better conduct the alcoholic fermentations in oenology in regards to possible deficiencies in grape musts, as well as allowing to investigate the influence held by vitamins in oenology in regards to wine aromatic profiles.