 IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Grapevine diversity and viticultural practices for sustainable grape growing 9 The effects of canopy side on the chemical composition of merlot, Cabernet-Sauvignon, and Carmenère (Vitis vinifera L.) Grapes during ripening

The effects of canopy side on the chemical composition of merlot, Cabernet-Sauvignon, and Carmenère (Vitis vinifera L.) Grapes during ripening

Abstract

AIM: Evaluating the effects of canopy side on the chemical composition of Merlot, Cabernet-Sauvignon and Carmenère fruit during ripening of a Vertical shoot positioning, VSP, trained experimental vineyard with north-south row orientation.

METHODS: Cabernet-Sauvignon, Carmenère, and Merlot grapes were harvested from a VSP trained experimental vineyard with north-south row orientation, located in the O’Higgins Region of Chile (34°20’06.9″S 70°47’54.3″W). For each cultivar, three representative rows were selected, and 200 berries were randomly collected in a 50 m span, keeping samples of both sides of the canopy separated. Samplings were carried out fortnightly from the veraison to the harvest (i.e., 0, 7, 21, 35 and 49, days post veraison). Soluble solids, titratable acidity, and pH were measured according to OIV-MA-AS313-01 and OIV-MA- AS313-15 methodologies. The content of glucose, fructose, malic acid, and tartaric acid in juices were analyzed by commercial enzymatic kits. Phenolic extracts were obtained by ultrasound maceration in a 50% ethanol-water mixture from which condensed tannins by the methylcellulose precipitation assay, total phenolics by Folin-Cioacalteu, and low molecular weight phenolics by HPLC-DAD were analyzed.

RESULTS: Contrary to some investigations, our results did not show major differences in fruit composition between the varieties and canopy side, particularly when major juice parameters such as sugars or acids were analyzed. Like so, the phenolics extracts did not show statistical differences when total phenolics or condensed tannins were compared according to canopy side but was possible to identify differences and highest phenolic amount within Cabernet-Sauvignon and Merlot compared to Carmenère; however, some of the low molecular weight phenolics significantly differ when varieties from different sides of the canopy were analyzed. For instance, catechin was significatively higher in fruit from the westside of the canopy in Cabernet-Sauvignon and Merlot, whilst east facing cluster from the three varieties had higher malvidin-3-glucoside concentration. Besides the prior, significant differences in the concentration of phenolics lengthwise the ripening, were observed for the tree varieties under study.

CONCLUSIONS:

Under the conditions of this study, only minor differences on fruit composition by varieties and canopy side were observed, particularly when it comes to low molecular weight phenolics.

DOI:

Publication date: September 2, 2021

Issue: Macrowine 2021

Type: Article

Authors

Paula A. Peña-Martínez, Liudis L. PINO María A. NAVARRO, Felipe LAURIE

Universidad de Talca, Chile.

Contact the author

Keywords

canopy side, phenolics, Cabernet-Sauvignon, Merlot, Carmenère

Citation

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Short-term relationships between climate and grapevine trunk diseases in southern French vineyards

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Spatial determination of areas in the Western Balkans region favorable for organic production

In problematic conditions for production of grapes and wine caused by the COVID-19 pandemic and the resulting occurrence of wine surpluses, producers are increasingly turning to the innovative viticulture and winemaking of products that are more appealing to the market and the consumers. On the other hand, consumption of the food safety or organic products, and therefore of organic grapes and wine, is increasingly common in the world, in particular in Europe. The Regional Rural Development Standing Working Group (SWG RRD), as a regional intergovernmental organization gathers actors in the viticulture and winemaking sector from states and territories of the Western Balkans (South-East Europe) in the Expert Working Group for Wine, with the aim of improving viticulture and winemaking in this region through joint activities. In accordance with the aforementioned, the SWG RRD is working on advancing organic production of grapes and wine, and on recognition of specificities of the terroir of wine-growing areas in Western Balkans. In addition, as part of the project “Facilitation of Exchange and Advice on Wine Regulations in Western Balkan Countries” helmed by the German Federal Ministry of Food and Agriculture, in addition to harmonization of relevant legislation with EU regulations, efforts are being invested towards recognition of organic wines. Within activities and project implemented by this organization, expert analyses and scientific research of the terroir of Western Balkans were carried out, and some of the results are presented in this paper.