qNMR metabolomics a tool for wine authenticity and winemaking processes discrimination

Abstract

qNMR Metabolomic applied to wine offers many possibilities. The first application that is increasingly being studied is the authentication of wines through environmental factors such as geographical origin, grape variety or vintage (Gougeon et al., 2019). Another less common approach is from a qualitative point of view by studying the various oenological practices used that are an integral part of the elaboration of a wine. We wondered whether quantitative NMR could be used to dissociate the physical or chemical processes commonly used in oenology. The objective of this work was to provide a better understanding of the interactions between oenological processes and wine by determining the metabolites responsible for differentiation through 1H-NMR fingerprinting and chemometrics. 

About 40 molecules were quantified on wine samples that have undergone several physical and chemical processes. Principal Component Analysis (PCA), Partial Least Squares Discriminant Analysis (PLS-DA) and S-score were performed for the analytical discrimination of winemaking processes. 

The results obtained show that qNMR combined with chemometrics allows to dissociate not only physical processes such as filtration, but also chemical processes such as maceration temperature, enzymatic treatment and fining. In addition, the metabolites involved in the discrimination of these winemaking processes could also be determined.

The 1H-NMR metabolomics is a fast technique that could be used as a tool to help professionals decide on technical itineraries.