Macrowine 2021
IVES 9 IVES Conference Series 9 HEAT BERRY : Sensitivity of berries ripening to higher temperature and impact on phenolic compounds in wine

HEAT BERRY : Sensitivity of berries ripening to higher temperature and impact on phenolic compounds in wine

Abstract

The grapevine is an important economical crop that is very sensitive to climate changes and microclimate. The observations made during the last decades at a vineyard scale all concur to show the impact of climate change on vine physiology, resulting in accelerated phenology and earlier harvest (Jones and Davis 2000). It is well-known that berry content is affected by the ambient temperature. While the first experiences were primarily conducted on the impact of temperature on anthocyanin accumulation in the grape, few studies have focused on others component of phenolic metabolism, such as tannins. Due to their chemical structure they are involved in the sensation of astringency / bitterness and play a key role in the quality of wines (Downey, Dokoozlian, and Krstic 2006). In a context of climate change and global warming, it is necessary to ask the question of the effect of temperature on the metabolism and its impact on wine quality. One of the goals of the HEAT BERRY project is to understand the physiological basis of the response of secondary metabolism to heat and microclimate, in grape berries, and their resulting effects on wine chemistry and organoleptic properties. A passive heating system made of polycarbonate screens has been set up at the vineyard. Field experiments conducted on Cabernet Sauvignon showed that this system induces 1 to 3°C increase in berry temperature. The heating system was set up in June at fruit set, and berries juices were sampled and used for ripening analysis between veraison and harvest time. The results of ripening agreed with previous studies: phenolic maturity and extractability of anthocyanins were decreased on heated berries. Nowadays, it is well-known that tannins nature within different berry tissues has an impact on bitterness and astringency (skins tannins mainly participate to the sensation of astringency, while seeds tannins also contribute to bitterness) as well as the percentage of each berry part. But nothing was shown about the importance of a temperature increase on these aspects. Microvinifications were performed on ripe (and over-ripe) berries. First, tastings demonstrated significant differences between wines from heated berries and non-heated berries in accordance with ripening process and berry compounds. Second, phenolics compounds (tannins levels, Dpm, tannins composition) were analyzed in berries and in wines. The analytical results will be compared with the sensory analysis in order to better understand the qualitative impact of heat treatment on berries and wine properties. Overall, the aim of HEAT BERRY is to address the poor knowledge of the effects of high temperatures on berry composition and wines. This should provide useful clues for the adaptation of viticulture to climate change.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Article

Authors

Julie Drappier*, Cécile Thibon, Darriet Philippe, Jing Wu, Laurence Geny-Denis, Michael Jourdes, Philippe Pieri, Robin Rabagliato, Serge Delrot

*ISVV

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Evaluation of Polarized Projective Mapping as a possible tool for attributing South African Chenin blanc dry wine styles

Multiple Factor Analysis (MFA) According to the Chenin blanc Association of South Africa, there are three recognized dry wine styles, Fresh and Fruity (FF), Rich and Ripe Unwooded (RRU), and Rich and Ripe Wooded (RRW), classically attributed with the help of sensory evaluation. One of the “rapid methods” has drawn our attention for the purpose of simplifying and making style attribution for large sample sets, evaluated during different sessions, more robust. Polarized Projective Mapping (PPM) is a hybrid of Projective Mapping (PM) and Polarised Sensory Positioning (PSP). It is a reference-based method in which poles
(references) are used for the evaluation of similarities and dissimilarities between samples.

Characterization of Glycosidically Bound Aroma Compounds of País cv. grapes of different Chilean zones

País grape has been estimated to arrive to Chile almost 500 years ago, being the first strain grown in this country. Traditionally, this grape has been used to mix with other varieties, to produce poor quality wines, but today is beginning to be used in the production of high quality wines. However, very little is known about the chemical characteristics of this variety. The aroma is one of the most important quality attributes of wine. Volatile compounds of this beverage may come from the grape (varietal aromas), from the fermentation process, from the ageing. The aromatic compounds are found in the grape in two forms: as free volatile compounds and as non-volatile compounds. The last ones, are aroma precursors present mainly as glycoconjugates formed by a sugar and an aglycone…

Dissecting the polysaccharide‐rich grape cell wall matrix during the red winemaking process, using high‐throughput and fractionation methods

Limited information is available on grape wall-derived polymeric structure/composition and how this changes during fermentation. Commercial winemaking operations use enzymes that target the polysaccharide-rich polymers of the cell walls of grape tissues to clarify musts and extract pigments during the fermentations. In this study we have assessed changes in polysaccharide composition/ turnover throughout the winemaking process by applying recently developed cell wall profiling approaches to both wine and pomace polysaccharides. The methods included gas chromatography for monosaccharide composition (GC-MS), infra-red (IR) spectroscopy and comprehensive microarray polymer profiling
(CoMPP) using cell wall probes.

Novel contribution to the study of mouth-feel properties in wines

In general, there is a well-established lexicon related to wine aroma and taste properties; however mouth-feel-related vocabulary usually includes heterogeneous, multimodal and personalized terms. Gawel et al.
(2000) published a wheel related to mouthfeel properties of red wine. However, its use in scientific publications has been limited. The authors accepted that the approach had certain limitations as it included redundant and terms with hedonic tone and some others were absent. It is of high interest to generate a mouth-feel lexicon and finding the chemical compound or group of compounds responsible for such properties in red wine. In the present work a chemical fractionation method has been developed.

Comparison of aroma-related compounds of carbonic maceration and traditional young red winemaking in case of Merlot by means of targeted metabolomic approach

Winemaking decisions and techniques are known to affect the final aromatic composition of red wines. Winemakers put a constant effort into the improved controlling of vinification procedures to achieve better quality. Anyway an increased customer’s demand for uniqueness is often forcing them to adjust and offer new and new interesting products. To support the producers, an improved knowledge on aromatic potential as affected by classical and alternative strategies is needed.