OENO IVAS 2019 banner
IVES 9 IVES Conference Series 9 OENO IVAS 9 OENO IVAS 2019 9 Analytical developments from grape to wine, spirits : omics, chemometrics approaches… 9 Integrated multiblock data analysis for improved understanding of grape maturity and vineyard site contributions to wine composition and sensory domains

Integrated multiblock data analysis for improved understanding of grape maturity and vineyard site contributions to wine composition and sensory domains

Abstract

Much research has sought to define the complex contribution of terroir (varieties x site x cultural practices) on wine composition. This investigation applied recent advances in chemometrics to determine relative contributions of vine growth, berry maturity and site mesoclimate to wine composition and sensory profiles of Shiraz and Cabernet Sauvignon for two vintages. 

Grape maturation was monitored using a berry sugar accumulation model and wines made from sequentially harvested grapes at three stages for each variety and vintage. Comprehensive targeted grape analysis of amino acids, carotenoids, sugars, organic acids, anthocyanins and volatile compounds were combined with targeted wine volatile and non-volatile chemical measures of composition and sensory descriptive analysis. Chemometric models of balanced sample sets derived from the pool samples were used in an ANOVA multiblock framework with orthogonal projection to latent structures (Boccard and Rudaz, 2016) to elucidate the relative importance of model design factors. 

Multiple data matrices derived from the experimental design factors are subtracted from the original data matrix to obtain pure effects and interaction submatrices with structured orthogonal data. A response matrix is derived from the positive eigenvalues associated with SVD of each effect matrix and residuals are then added to each submatrix prior to kernel OPLS. Model performance evaluated from residual structure ratio (RSR), goodness of fit (R2Y) and permutation testing identified the significant factors from each model. Projection of sample scores of significant factors against scores of the residual matrix is used to assess sample clusters with confidence intervals based on Hotelling T2. 

Loadings from significant experimental factors of each model were used for hierarchical cluster analysis (HCA) with Euclidean distance measures and Wards grouping criteria. Prior to HCA scores and loadings are rotated to consistent presentation of factor levels in model plots. A conservative interpretation of loadings heat maps was considered appropriate and a summary heat map for explanatory factors is presented that enable interpretation of the impact of cultivar, site (soil x mesoclimate), grape maturity and region on grape and wine composition. The integrated data driven approach used in this investigation may be of assistance for other investigators for omics based experiments.

Ref: Boccard, J. & Rudaz, S. 2016. Anal Chim Acta. 920:18-28.

DOI:

Publication date: June 19, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Leigh Schmidtke, Guillaume Antalick, Katja Suklje, John Blackman, Alain Deloire

National Wine and Grape Industry Centre, Charles Sturt University, Locked Bag 588 – Wagga Wagga – New South Wales 2678 – AUSTRALIA
Wine Research Centre, University of Nova Gorica, Vipavska, 5000 Nova Gorica, Slovenia
Agricultrual Institute of Solvenia, Lubljana, 1000, Slovenia
Montpellier SupAgro, Montpellier 34060,

Contact the author

Keywords

AMOPLS, sequential harvest, berry sugar accumulation, targeted metabolomics 

Tags

IVES Conference Series | OENO IVAS 2019

Citation

Related articles…

Spatial variability of grape berry maturation program at the molecular level 

The application of sensors in viticulture is a fast and efficient method to monitor grapevine vegetative, yield and quality parameters and determine their spatial intra-vineyard variability. Molecular analysis at the gene expression level can further contribute to the understanding of the observed variability by elucidating how pathways responsible for different grape quality traits behave in zones diverging for one or the other parameter. The intra-vineyard variability of a Cabernet Sauvignon vineyard was evaluated by a standard Normalized Difference Vegetation Index (NDVI) mapping approach, employing UAV platform, accompanied by detailed ground-truthing (e.g. vegetative, yield, and berry ripening compositional parameters) that was applied in 14 spots in the vineyard. Berries from different spots were additionally investigated by microarray gene expression analysis, performed at five time points from fruit set to full ripening.

FLAVANOL COMPOSITION OF VARIETAL AND BLEND WINES MADE BEFORE AND AFTER FERMENTATION FROM SYRAH, MARSELAN AND TANNAT

Background: The Flavan-3-ol extraction from grape skin and seed during red-winemaking and their retention into wines depend on many factors, some of which are modified in the winemaking of blend wines. Recent research shows that Marselan, have grapes with high proportion of skins with high concentrations of flavanols, but produces red-wines with low proportion of skin derived flavanols, differently to the observed in Syrah or Tannat. But the factors explaining these differences are not yet understood.

Distribution and sensory impact of new oak wood-derived compounds in wines

Despite the numerous research studies carried out in recent years, the study of wine aroma remains of great interest due to its complexity. Wine maturation in oak barrels is described as an important step in the production of quality wines. In fact, oak wood develops several aromatic nuances through its toasting which can be released into the wine. A great deal of work has been performed in order to identify the wood-derived volatile compounds that contribute to wine aroma (e.g., whisky-lactone, maltol, eugenol, guaiacol, vanillin).

The influence of soil management practices on functional traits and biodiversity of weed communities in Swiss vineyards

Green cover in vine rows provides many ecological services, but can also negatively impact the crop, depending on the weed species. The composition of a vineyard weed community is influenced by many parameters. Ensuring an evolution of the vine row flora into a desired direction is therefore very complex. A key step towards this goal is to know which factors influence the establishment of the weed community and which types of communities are best suited for vineyards. In this study, we analysed the weed communities of several vineyards in the Lake Geneva region (379 botanical surveys on 117 plots), with the aim to highlight the links between soil management practices (chemical and mechanical weeding, mowing, mulching roll) and phytosociological profiles, biodiversity and selected functional traits (growth forms, life strategies, root depth). T

Hormone metabolism regulates fruit maturation in a slow ripening grape genotype

Context and purpose of the study. Rising temperatures and prolonged heat accelerate berry sugar accumulation in advance of the accumulation of compounds responsible for aroma, colour and mouthfeel.