Macrowine 2021
IVES 9 IVES Conference Series 9 Evaluation of intrinsic grape berry and cluster traits for postharvest withering kinetics prediction

Evaluation of intrinsic grape berry and cluster traits for postharvest withering kinetics prediction

Abstract

To make some particular wine styles (e.g., Amarone), grapes are harvested and stored in dehydrating rooms before vinification, in a process called withering. This practice increases the concentration of sugars and other solutes and encourages the accumulation of unique aroma compounds in berries. Previous investigations evidenced that the kinetics of grape dehydration highly affects the quality of the produced wine. Along with the well-known effects of the environmental conditions, the cluster and berry morphology have an important role in the determination of the grape water loss rate. However, the relative contribution of each cluster/berry physical trait to the dehydration rate and the possibility to predict the latter parameter in advance, are poorly studied aspects. The aim of this work was to investigate the effect of several grape physical/morphological parameters on the withering kinetic rate, individuating potential predictors of the grapes behavior during postharvest dehydration. Four red wine grape cultivars, Corvina, Corvinone, Cabernet-Sauvignon and Cavrara, were harvested at commercial ripening and their cluster compactness, berry surface area to volume ratio, skin thickness and skin waxes quantity were measured. Furthermore, a novel rapid dehydration test in a controlled forcing environment (50 °C; 400 mbar; 24 h) was applied on grape clusters to assess their intrinsic tendency to lose water. The grapes were then withered for 77 days, under controlled environmental conditions simulating the commercial process, and the dehydration kinetic rates were obtained. Multivariate and correlation analyses were employed to search and score the relation between each measured parameter and the withering kinetic rate. The parameters which were pointed out as good predictors of the grapes water loss attitude were the skin thickness, berry surface area to volume ratio and cluster compactness. However, intra-cultivar analyses performed on Corvina and Corvinone separately have not identified parameters with significant correlations to the withering kinetic rate, likely because of the very low variability observed among accessions of the same cultivar.

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Ron Shmuleviz 

Department of Biotechnology, University of Verona, Via della Pieve 70, 37029 – San Floriano, San Pietro in Cariano – VR, Italy., Giovanni Battista TORNIELLI, Department of Biotechnology, University of Verona, Via della Pieve 70, 37029 – San Floriano, San Pietro in Cariano – VR, Italy.

Contact the author

Keywords

wine grapes, dehydration kinetics, withering, fruit morphology, amarone

Citation

Related articles…

Application of satellite-derived vegetation indices for frost damage detection in grapevines

Wine grape production is increasingly vulnerable to freeze damage due to warming climates, milder winters, and unpredictable late spring frosts. Traditional methods for assessing frost damage in grapevines which combine fieldwork and meteorological data, are expensive, time-consuming, and labor-intensive. Remote sensing could offer a rapid, inexpensive way to detect frost damage at a regional scale. Remote sensing approaches were used to assess freeze damage in grapevines by evaluating satellite-derived vegetation indices (VIs) to understand the severity and spatial distribution of damage in several New York vineyards immediately after a frost event (May 17th-18th, 2023). PlanetScope 3m satellite images acquired before and after the freeze were used to map damage and measure changes in VIs for vineyards in the Finger Lakes region.

Read More

Mitigating the effects of climate change on berry composition by canopy management

Primary and secondary metabolites are major components of grape composition and their balances define wine typicality

Read More

Generation of functional chitosan derivatives to better understanding the antiseptic effect on Brettanomyces bruxellensis in wine

The addition of fungal chitosan in wine is allowed since 2009 to release some spoilage microorganisms such as Brettanomyces bruxellensis (OIV/OENO 338A/2009; EC 53/2011). This yeast is able to produce volatil phenols and is responsible of organoleptic deviations compromising quality and typicality of red wines [1]. Despite the fact that fungal chitosan is highly renewable, no toxic and non-allergenic, its use remains marginal because this treatment is relatively recent (compare to sulphites treatment) and information are contradictory between different studies described in literature. For all these reasons,

Read More

Mining microbiome data to identify antagonists of grapevine downy mildew (Plasmopara viticola)

Vineyards are home to a myriad of microorganisms that interact with each other and with the vines. Some microorganisms are plant pathogens, such as the oomycete Plasmopara viticola, causing grapevine downy mildew. Others have a positive effect on vine health, such as disease biocontrol agents. These beneficial plant-microbe and microbe-microbe interactions have gained more attention in recent years because they could represent an alternative to the use of fungicides in viticulture.

Read More

Mannoproteins from oenological by-products as tartaric stabilization and color agents in white and red wines

Climate change is drastically modifying grape composition and wine quality. As consequence, must and wines are becoming unbalanced, with high sugar concentration, increased alcohol content, lower acidity, excessive astringency, color instability and also a rise in the incidence of tartaric instability is being showed.

Read More