terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Wine racking in the winery and the use of inerting gases

Wine racking in the winery and the use of inerting gases

Abstract

The O2 uptake in the different winemaking processes is generally considered to be negative for the sensory characteristics of white and rosé wines. Wine racking is a critical point of O2 uptake, as the large surface area of the wine exposed during this operation and the inability to maintain an effective inert gas blanket over it.

The objective was to study O2 uptake during the racking of a model wine without using inert gases and to compare it with the purging of the destination tank with different inert gases. In addition, inert gases were also used to protect the wine in the racking tank by blanketing the wine. Finally, a full-scale inerting study was carried out in a commercial winery during the racking of a white wine to evaluate the effectiveness of the use of different inert gases. Tank ullage space oxygen (HSO) and wine dissolved oxygen (DO) were monitored in different points during the wine racking.

Purging an empty tank with different inert gases was effective being the CO2:Ar (20:80) mixture clearly the most effective, requiring less gas volume to displace O2. The opposite result was found with N2 because it worked in dilution mode. Although from an economic viewpoint, the most recommendable gas was CO2.

The level of protection of the racked wine and the headspace over the racked wine in the empty destination tank differed depending on the gas used and the thickness (% of the tank volume) of the blanket formed with each gas. Based on the results obtained, purging with 25% of the empty tank volume of each inert gas is recommended to protect racked wine in a good cost-benefit way. To keep the headspace of the racking tank inert, blanketing with 50% of tank volume of Ar, CO2 or the mixture of both were sufficient. Applying different volumes of gas had little effect on the DO of the wine at the tank outlet.

Acknowledgements: This research has been funded by ITACyL through a collaboration agreement with the University of Valladolid and the Fundación del Parque Científico de la Universidad de Valladolid. This project has received funding from AEI and Ministry of Science and Innovation MICINN (RTC2019-007319-2 Oxiprestop Project). The authors would like to tank Carburos Metálicos (Air Products group) and IVG Colbachini S.p.A for their material Support.

DOI:

Publication date: October 13, 2023

Issue: ICGWS 2023

Type: Poster

Authors

Ignacio Nevares*, Rubén del Barrio Galán, Elena Pérez-Cardo, María Asensio-Cuadrado, Ana Martínez-Gil, Luis Miguel Cárcel, Alberto Gómez, Sonia Villanueva, Julio A. Pinto Solano, Carlos Moro González, and Maria del Alamo-Sanza

Grupo UVaMOX-Universidad de Valladolid. Avda. Madrid 50. 34001 Palencia, Spain

Contact the author*

Keywords

inert gases, racking wine, blanketing, oxygen, purging

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Vineyard yield estimation using image analysis: assessing bunch occlusions and its dependency on fruiting zone canopy features

Performing accurate vineyard yield estimation is of upmost importance as it provides important benefits to the whole vine and wine industry. Recently, image-analysis approaches have been explored to address this issue however this approach has as main challenge the bunch occlusion, mostly by vegetation but also by neighboring bunches. The present work aims at assessing the magnitude of bunch occlusion by neighboring bunches and to evaluate its dependency on a selection of vegetative and reproductive vine parameters assessed at fruiting zone. Forty vine segments (1 m) of two vineyard plots of the white cultivars ‘Alvarinho’ and ‘Arinto’ were assessed for vegetative and reproductive features at fruiting zone and imaged with a 2D camera.

Antimicrobial activity of oenological polyphenols against Gram positive and Gram negative intestinal multidrug-resistant bacteria

Bacterial antibiotic resistance is a major current health problem. Polyphenols have demonstrated antibacterial activity, and in this work we studied the effect of oenological polyphenols on the growth of intestinal multidrug-resistant strains of human and animal origin. Two Enterococcus faecium strains, resistant to vancomycin and other antibiotics, and four Escherichia coli strains, resistant to ampicillin and other antibiotics, were included in this study. All strains showed multidrug resistant phenotypes and genotypes to at least two antibiotic families.

Impact of polyclonal selection for abiotic stress tolerance on the yield and must quality traits of grapevine varieties

The effects of climate change in viticulture are currently a major concern, with heat waves and drought affecting yield, wine quality, and in extreme cases, even plant survival. Ancient grapevine varieties have high intravarietal genetic variability that so far has been explored successfully to improve yield and must quality. Currently, there is little information available on intravarietal variability regarding responses to stress. In the current work, the intravarietal genetic variability of several Portuguese varieties was studied for yield, must quality, and tolerance to abiotic stress, through indirect, rapid, and nondestructive measurements carried out in the field.

Perception, liking and emotional response of tropical fruit aromas in Chardonnay wines

Tropical fruit aromas in wines are thought to be important to wine consumers, although there is little research to confirm this statement. With so many wine styles available, it has become important to understand the qualities that are desirable to consumers and how to achieve those qualities. Thiols and esters are compounds that have been found to cause tropical fruit aromas in chardonnay (ref). Fermentation temperature gradients and skin contact were found to increase these compounds using micro scale fermentations. This work aimed to scale up these fermentations/operations to determine if the desired tropical fruit aromas could still be achieved and if there is a perceivable difference in tropical fruit aromas, liking, and emotional response in the wines at the consumer level.

Early defoliation positively enhances bioactive composition of berries with no effect on cuticle characteristics

Leaf removal in the fruit-zone has been employed to improve cluster light exposure and ventilation and therefore increase metabolite accumulation and reduce botrytis incidence in berries. When applied before flowering (early defoliation – ED), it can also decrease cluster compactness and regulate yield in high-yielding varieties. This study aimed to evaluate the impact of ED on the physiology and metabolism of Aragonez (syn. Tempranillo) berries along the ripening period. The experiment was set up in 2013 at a commercial vineyard located in the Lisbon winegrowing region.