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…

Ability of lactic acid bacterial laccases to degrade biogenic amines and OTA in wine

Two of the most harmful microbial metabolites for human health that can be present in wines and either fermented or raw foods are biogenic amines (BA) and ochratoxine A (OTA). Winemakers are aware of the need to avoid their presence in wine by using different strategies, one of them is the use of enzymes. Some recombinant laccases have been characterized and revealed as potential tools to degrade these toxic compounds in wine[1], specifically biogenic amines[2].

Development of a new method for detecting acetic acid bacteria in wine

The presence of acetic acid bacteria in wine can lead to the appearance of acetic acid at concentrations above the perception threshold, causing the wine rejection by the consumer. During the winemaking process, avoiding the presence of acetic acid bacteria is very difficult, as there is always a residual population accompanying the wine[1], and the problem arises with the significant development of these microorganisms that metabolizes large amounts of acetic acid.
The concern of wineries to control the presence of acetic acid bacteria in wines during their conservation is due to the absence of simple and effective analyses that allow the detection of these microorganisms in the initial stages.

The tolerance of grapevine rootstocks to water deficit is related to root morphology and xylem anatomy traits 

Climate change is altering water balances, thereby compromising water availability for crops. In grapevine, the strategic selection of genotypes more tolerant to soil water deficit can improve the resilience of the vineyard under this scenario. Previous studies demonstrated that root anatomical and morphological traits determine vine performance under water deficit conditions. Therefore, 13 ungrafted rootstock genotypes, 6 commercial (420 A, 41 B, Evex 13-5, Fercal, 140 Ru y 110 R), and 7 from new breeding programs (RG2, RG3, RG4, RG7, RG8, RG9 and RM2) were evaluated in pots during 2021 and 2022.

White grape must processed by UHPH as an alternative to SO2 addition: Effect on the phenolic composition in three varieties

The quantity and distribution of polyphenols in musts play a fundamental role in the white winemaking. This is because these substances are exposed to oxidation reactions, which are catalysed by the polyphenol oxidase (PPO), leading to a decrease in the quality of the wines produced. PPO is inactivated by SO2, but currently, due to the restrictions of the legislation, other methodologies are being investigated. Ultra-High Pressure Homogenization (UHPH) is a non-thermal physic technology that exerts an ultrahigh pressure pumping (>200 MPa) of a fluid through a valve in a continuous system.

Biodiversity and biocontrol ability of Trichoderma natural populations in soil vineyards from Castilla y León region (Spain)

Trichoderma is a microorganism present in many agricultural soils and some of its species could be used as natural biological control agents. In this work, the presence of natural populations of Trichoderma was estimated in soil vineyard and its biocontrol capacity against Phaeoacremonium minimum, one of the main agent causals of grapevine trunk diseases instead of using pesticides. Moreover, physicochemical variables in soil such as pH, organic matter and nutrients were evaluated to determine a possible correlation to natural populations of Trichoderma.