 IVES 9 IVES Conference Series 9 Phenolic extraction and mechanical properties of skins and seeds during maceration of four main italian red wine grape varieties

Phenolic extraction and mechanical properties of skins and seeds during maceration of four main italian red wine grape varieties

Abstract

AIM: Red grape varieties are characterized by different phenolic contents (prominently tannins and anthocyanins) found in skins and seeds. The extractability of these compounds varies during maceration, as well as the mechanical properties of skins and seeds. Four main Italian red winegrape varieties were tested to understand these differences during a simulated maceration process.

METHODS: Vitis vinifera L. cv. Aglianico, Nebbiolo, Primitivo, and Sangiovese grape skins, seeds, and joint skin+seeds were subjected to 10-day simulated maceration in a buffer solution (pH 3.40), with increasing contents of ethanol to simulate the fermentation trend. The phenolic extractable content (tannins and anthocyanins by spectrophotometry and HPLC) was evaluated during the simulated maceration. Mechanical-acoustic properties of skins and seeds were performed before and after maceration.

RESULTS: The combined total phenolics release during the maceration of separately-extracted seeds and skins were higher compared to the joint extraction (seeds+skins); in this latter case, the seeds contribution become significant (p < 0.05) after 3 (Nebbiolo), 4 (Aglianico) or 10 days (Primitivo and Sangiovese). In three cases out of four the anthocyanin content was found slightly reduced when the seeds were jointly present: these appeared red-coloured at the end of the maceration, and a further extraction and quantitation of the colouring matter retained by seeds was conducted. Diverging effects on the skin or seeds mechanical-acoustic measurements were found with the maceration process, depending by the variety.

CONCLUSIONS

Varietal differences were highlighted in phenolic compounds simulated extraction from solid parts, particularly for seeds contribution and for their ability to hold colour pigments.

ACKNOWLEDGMENTS

MIUR project PRIN n. 20157RN44Y. P. Arapitsas, A. Gambuti, M. Marangon, L. Moio, L. Nouvelet, G. Parpinello, D. Perenzoni, L. Picariello, D. Slaghenaufi, G.B. Tornielli, A. Versari, S. Vincenzi

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Simone Giacosa

University of Torino, Italy – Maria Alessandra PAISSONI, University of Torino, Italy – Susana RÍO SEGADE, University of Torino, Italy – Andrea CURIONI, University of Padova, Italy – Fulvio MATTIVI, University of Trento, Italy – Paola PIOMBINO, University of Napoli, Italy – Arianna RICCI, University of Bologna, Italy – Maurizio UGLIANO, University of Verona, Italy – Vincenzo GERBI, University of Torino, Italy – Luca ROLLE, University of Torino, Italy

Contact the author

Keywords

italian red winegrapes, phenolic extraction, anthocyanins, tannins, grape seeds

Citation

The importance of soil and geology in tasting terroir; a case history from the Willamette valley, Oregon

Wines differ from each other based on seven different factors: the type of grape; the bedrock geology and resulting soils; the climate; the soil hydrology; physiography of the site; the winemaker and the vineyard management techniques. The first five of these factors make up what the French call terroir, “the taste of the place”.

Chemical activation of ABA signaling in grapevine through ABA receptor agonists

Grapevine (Vitis vinifera) and its derived products, in terms of cultivated area and economic volume, constitute the most relevant fruit crop in the world (7.5 million cultivated hectares). In the current context of climate change, the wine sector faces unprecedented challenges to satisfy a growing demand for wines of greater quality through sustainable viticulture. Global warming threatens quality wine production in Mediterranean wine regions in particular. The increase in heatwaves and drought episodes accelerate the vine phenology and alter the ripening and composition of grapes and wine. Extreme abiotic stress episodes compromise grape production and plant survival, intensifying the pressure on the use of limited resources like water. Abscisic acid (ABA) is an important hormone in the ripening of certain fruits and in plant response to abiotic stress.

Differential responses of red and white grape cultivars trained to a single trellis system – the VSP

Commercial grape production relies on training grapevine cultivars onto a variety of trellis systems. Training allows for well-lit leaves and clusters, maximizing fruit quality in addition to facilitating cultivation, harvesting, and diseases control. Although grapevines can be trained onto an infinite variety of trellis systems, most red and white cultivars are trained to the standard VSP (Vertical Shoot Positioning) system. However, red and white cultivars respond differently to VSP in fruit composition and growth characteristics, which are yet to be fully understood. Therefore, the objective of this study was to examine the influence of the VSP trellis system on fruit composition of three red, Cabernet Sauvignon, Merlot and Syrah, and three white, Chardonnay, Riesling, and Gewurztraminer cultivars grown under uniform growing conditions in the same vineyard. All cultivars were monitored for maturity and harvested at their physiologically maximum possible sugar concentration to compare various fruit quality attributes such as Brix, pH, TA, malic and tartaric acids, glucose and fructose, potassium, YAN, and phenolic compounds including total anthocyanins, anthocyanin profile, and tannins. A distinct pattern in fruit composition was observed in each cultivar. In regards to growth characteristics, Syrah grew vigorously with the highest cluster weight. Although all cultivars developed pyriform seeds, the seed size and weight varied among all cultivars. Also varied were mesocarp cell viability, brush morphology, and cane structure. This knowledge of the canopy architectural characteristics assessed by the widely employed fruit compositional attributes and growth characteristics will aid the growers in better management of the vines in varied situations.

Isotope composition of wine as indicator of terroir spatial variability

The goal of this work was to determine the spatial variability of terroir using the isotope composition of wine. Carbon (δ13C) and oxygen (δ18O) stable isotope composition was measured in wines from Tempranillo (Vitis vinifera L.) vineyard, located in Rioja Appellation (Spain). Stable isotope composition, leaf area, vigour, yield components, grape and wine composition were determined in a grid of 85 geo-referenced points, that was drawn across the 5 ha vineyard area

Factors involved in the acumulation of acetic acid inside the grapes during winemaking by carbonic maceration

Vinification by carbonic maceration (CM) is based in the anaerobic fermentative metabolism also called intracellular fermentation (IF).