The role and quantification of vitamins in wine: what do we know?

Abstract

AIM: Vitamins are essential compounds to numerous organisms, including yeasts, and appear highly significant during winemaking processes. Acting as cofactors in major yeast metabolic pathways, such as those of alcohols, amino acids and fatty acids, it appears very likely that their involvement in fermentation courses, as well as in the development of aromatic compounds in wine is consequential.

METHODS: Numerous assays have been developed to determine and quantify vitaminic contents in grape musts and wines. Microbial assays, relying on the specific growth requirements of selected microorganisms, were the earliest methods used pursuing this goal, however poorly precise and accurate. Methods relying on vitamin properties, such as acid titrations and spectrophotometry have also been used to quantify vitamins in grape musts and wines, although they require specific physicochemical properties, and do not allow for simultaneous determination of several vitamin groups.

RESULTS: As a consequence, contemporary techniques, such as chromatography-based methods, stand as efficient means to quantify vitamins in grape musts. However, no method has recently been developed to assay vitamin contents in this specific matrix. Similarly, assays relying on spectroscopy and electrophoresis, proved efficient in simultaneously quantifying vitamins in several fruit matrixes, appear promising for extension towards the grape must and wine matrixes. In addition, winemaking processes, such as the addition of sulfites or clarifying agents, or vatting lengths have been shown to significantly impact vitamin contents.

CONCLUSION

The development of more methods to quantify vitamins in grape musts, relying on more sensitive and precise recent analytical techniques could offer ground for a broad range of prospects in the wine science field. Such developments could support better comprehensions of yeast requirements during winemaking, and allow for finer modulations of the processes, as well as elucidate the role of vitamins in the development of aroma in wines