OENO IVAS 2019 banner
IVES 9 IVES Conference Series 9 Red wine astringency: evolution of tribological parameters during different harvest dates

Red wine astringency: evolution of tribological parameters during different harvest dates

Abstract

Astringency is a specific oral sensation dominated by dryness and puckering feeling and is one of the leading quality factors for red wines, as well as some fruit products. Based on this sensory parameter, are made relevant decisions in wine production including the moment of grape harvest (phenolic ripeness), the time and intensity of maceration, the time and type of aging process, and the target market of wines. Notably, the selection of the optimal grape astringency during ripeness is one of the most crucial decisions in winemaking. However, grape astringency is an attribute challenging to evaluate and standardize by tasters since the grapes are heterogeneous and generate along their ripeness different sensory descriptors, such as the typical drying astringency found in immature grapes. Here we used a tribological system to determinate the red wine astringency produced on different harvest dates. Mixtures of whole human saliva and red wines as Cabernet Sauvignon and Carménère, with similar tannin content but different sub-quality (rough and soft/velvety, respectively), were evaluated by their lubrication behavior. Red wines produced significant changes in the saliva friction coefficient during the harvest dates, with an opposite evolution between the Cabernet Sauvignon and Carménère. Also, microstructure observation revealed differences between conformation and surface of the tan-ninprotein aggregates of both red wines, suggesting a correlation between them and the astringency sensory perception. Results from this work demonstrate that tribology techniques can be a useful tool for both to evaluate astringency on red wines and to help us to understand the phenomenon of sub-qualities.

DOI:

Publication date: June 19, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Natalia Brossard, Giuseppina Parpinello, Fernando Osorio, Edmundo Bordeu, Jianshe Chen

Department of Food Sciences, University of Bologna, P.za Goidanich 60, I-47023 Cesena, Italy.
Department of Food Science and Technology, University of Santiago Chile, Avda. Libertador Bernardo O’Higgins 3363, San-tiago, 9170022, Chile.
Department of Fruit Trees and Enology, Pontifical Catholic University of Chile, Avda. Vicuña Mackenna 4860, Santiago, 7820436, Chile.
School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, P. R. China.

Contact the author

Keywords

wine astringency, tribology, human saliva, harvest dates 

Tags

IVES Conference Series | OENO IVAS 2019

Citation

Related articles…

Metabolomics of grape polyphenols as a consequence of post-harvest drying: on-plant dehydration vs warehouse withering

A method of suspect screening analysis to study grape metabolomics, was developed [1]. By performing ultra-high performance liquid chromatography (UHPLC) – high-resolution mass spectrometry (HRMS) analysis of the grape extract, averaging 320-450 putative grape compounds are identified which include mainly polyphenols. Identification of metabolites is performed by a new HRMS-database of putative grape and wine compounds expressly constructed (GrapeMetabolomics) which currently includes around 1,100 entries.

Hydroxycinnamic acids in grapes and wines made of Tannat, Marselan and Syrah from Uruguay

Background: hydroxycinnamic acids (HCA), present in pulp and skin of grapes, are relevant compounds in red winemaking

Grape ripening timing as a base for viticultural zoning: an agro-ecological approach

Due to the central role of the ripening timing in the evaluation of the varietal response to the environmental resources, a method to manage maturation curves has been developed. The method produces an index of veraison precocity and overcomes several methodological problems, like the visual evaluation of the veraison point and the multi-annual and multi-varieties data processing. It is based on a statistical and mathematical processing of the sugar ripening curves.

AGING PATTERNS OF VARIETAL VOLATILE PROFILES OF WHITE WINES: A CASE STUDY ON 18 ITALIAN VARIETAL WHITE WINES

During wine aging many compositional changes take place. In particular, aroma undergoes dramatic modifications through a wide range of reactions that to date are only partly understood. Italy owns one of the largest ampelographic heritages worldwide, with over three-hundred different varieties. Among these, many white grapes are employed for the production of dry still white wines. Some of these wines are consumed young while others are more prone to aging. For many of these wines, the aging patterns related to volatile composition are still unknown.

Proteomic profiling of grape berry presenting early loss of mesocarp cell vitality

From fruit set to ripening, the grape berry mesocarp experiences a wide range of dynamic physical, physiological, and biochemical changes, such as mesocarp cell death (MCD) and hydraulic isolation. The premature occurrence of such events is a characteristic of the Niagara Rosada (NR) variety, utilised as table grapes and winemaking. In our opinion, the onset of ripening would not cause MCD, but a down-regulation of respiratory enzymes during the early loss of cell viability, while maintaining membrane integrity. For this, we investigated three distinct developmental stages (green (E-L33), veraison (E-L35), and ripe (E-L39)) of NR berries by label-free proteomics, enzymatic respiratory activity and outer mesocarp imaging. Cell wall-modifying proteins were found to accumulate differently throughout ripening, while cytoplasmic membranes continue intact.