WAC 2022 banner
IVES 9 IVES Conference Series 9 WAC 9 WAC 2022 9 4 - WAC - Oral presentations 9 Wine lees: characterization and valorization by kombucha fermentation

Wine lees: characterization and valorization by kombucha fermentation

Abstract

Winemaking generates various types of residues (vine shoots, stalks, pomace, wine lees and filtration cakes) which can have a notable environmental and economic impact. Wine by-products are rich in bioactive compounds and therefore their valorization can be beneficial on different levels. Lees are the material that settles after vinification, and consist mainly of yeast cells, grape skins, tartrates, phenolic compounds, and other residues. The objective of this study was to valorize the wine lees by the Kombucha process in order to create a new beverage. 

Kombucha is a traditional beverage obtained by the fermentation of sweetened tea with a symbiotic culture of yeast and bacteria. The consumption of kombucha is associated with many health benefits due to its rich composition in bioactive compounds. Different substrates were used as raw material for Kombucha fermentation, and the obtained beverages displayed an increase in the concentration of biological compounds and enhancement of health activities. 

Red wine lees used in this study presented a pH of 3.31 ± 0.01, a total acidity of 2.86 ± 0.45 g/L (sulfuric acid equivalent), a total polyphenol content of 2041 ± 233.35 mg/L GAE (Gallic acid equivalent), and an antioxidant activity of 59.03 ± 4.25 % inhibition against DPPH radicals. 

In order to ferment the wines lees by Kombucha Scoby, wine lees were subject to two dilutions of 1:2 and 1:4. These dilutions were fermented for 24 days at 25°C. Samples were taken each 3 days in order to monitor the physico-chemical evolution of the new beverage. Results showed that the sugar consumption (70 g/L) was not complete after 24 days of fermentation. pH of the new beverage is 2.88. Fermentation time and substrate concentration influenced the studied variables, for instance the strongest antioxidant activity was detected on the 9th day for the lees kombucha diluted to the half (93.27%) whereas the highest quantity of polyphenols was found on day 21 (1599.30 mg/L GAE).

DOI:

Publication date: June 14, 2022

Issue: WAC 2022

Type: Article

Authors

Youssef El Rayess, Nathalie Barakat, Sandra Beaufort, Samar Azzi-Achkouty, Ziad Rizk, Chantal Ghanem, Abdo Tannoury, Jalloul Bouajila, Patricia Taillandier, Youssef El Rayess

Presenting author

Youssef El Rayess – Department of Agriculture and Food Engineering, Holy spirit University of Kaslik, Jounieh, Lebanon

Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France | Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France | Department of Agriculture and Food Engineering, School of Engineering, Holy Spirit University of Kaslik, Jounieh, Lebanon | Lebanese Agricultural Research Institute, Fanar Station, P.O. Box 90-1965, Jdeidet El-Metn, Fanar, Lebanon | Lebanese Agricultural Research Institute, Fanar Station, P.O. Box 90-1965, Jdeidet El-Metn, Fanar, Lebanon | Lebanese Agricultural Research Institute, Fanar Station, P.O. Box 90-1965, Jdeidet El-Metn, Fanar, Lebanon | Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France | Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France | Department of Agriculture and Food Engineering, School of Engineering, Holy Spirit University of Kaslik, Jounieh, Lebanon 

Contact the author

Keywords

wine lees-Kombucha-polyphenols-antioxidants

Tags

IVES Conference Series | WAC 2022

Citation

Related articles…

Climate change projections to support the transition to climate-smart viticulture

The Earth’s system is undergoing major changes through a wide range of spatial and temporal scales as a response to growing anthropogenic radiative forcing, which is pushing the whole system far beyond its natural variability. Sources of greenhouse gases largely exceed their sinks, thus leading to a strengthened greenhouse effect. More energy is thereby being supplied to the system, with inevitable shifts in climatic patterns and weather regimes. Over the last decades, these modifications have been manifested in the full statistical distributions of the atmospheric variables, with dramatic changes in the frequency and intensity of extremes. Natural hazards, such as severe droughts, floods, forest fires, or heatwaves, are being triggered by extreme atmospheric events worldwide, thus threatening human activities. Viticultculture is not only exposed to changing climates but is also highly vulnerable, as grapevine phenology and physiological development are strongly controlled by atmospheric conditions. Therefore, the assessment of climate change projections for a given region is critical for climate change adaptation and risk reduction in viticulture. By adopting timely and suitable measures, the future sustainability and resiliency of the sector can be fostered. Climate-grapevine chain modelling is an essential tool for better planning and management. However, the accuracy of the resulting projections is limited by many uncertainties that must be duly taken into account when transferring knowledge to stakeholders and decision-makers. Climate-smart viticulture will comprise ensembles of locally tuned strategies, envisioning both adaptation and mitigation, assisted by emerging technologies and decision-support systems.

Impact of changes in pruning practices on vine growth and yield

A gradual decline in vineyards has been observed over the past twenty years worldwide. This might be explained by the climate change, practices change or the increase of dieback diseases. To increase the longevity of vines, we studied the impact of different pruning strategies in four adult and four young vineyards located in France and Spain. In France, vineyards were planted with Cabernet franc on 3309C while Spanish trials were planted with Tempranillo grafted on 110R. Vegetative expression, yield, quality of berries and wood vessels conductivity were measured. The distribution of vegetative expression, yield and berry composition between primary and secondary vegetation were quantified. Finally, tomography was used to evaluate the implication of the treatments on sap flows.
First results show that i) the respectful pruning leads to an increase of 30 to 50% more secondary shoots than the aggressive pruning in France and between 15 and 20% in Spain, ii) there is no major effect on the yield over the first two years following the implementation of the new pruning practices, although the proportion of clusters from suckers is higher on the respectful pruning method. On young vines, the development of the trunk according to a respectful pruning leads to a loss of harvest 2 years after planting. This is due to the removal, on the future trunk, of the green suckers which carrying bunches. This operation carried out in spring rather than during winter pruning, would promote a better leaf / fruit balance when the plant comes into production, and could lead to better hydraulic conduction in the vessels of the trunk. Maintaining these trials for several years will provide more robust data to assess the impact of these practices on the vines over the long term.

De novo Vitis champinii whole genome assembly allows rootstock-specific identification of potential candidate genes for drought and salt tolerance

Vitis champinii cultivars Ramsey and Dog-ridge are main choices for rootstocks to adapt viticulture in semi-arid and arid regions thanks to their distinctive tolerance to drought and salinity. However, genetic studies on non-vinifera rootstocks have heavily relied on the grapevine (Vitis vinifera) reference genome, which difficulted the assessment of the genetic variation between rootstock species and grapevines. In the present study, this limitation is addressed by introducing a novo phased genome assembly and annotation of Vitis champinii. This new Vitis champinii genome was employed as reference for mapping RNA-seq reads from the same species under drought and salt stresses, and for comparison the same reads were also mapped to the Vitis vinifera PN40024.V4 reference genome. A significant increase in alignment rate was gained when mapping Vitis champinii RNA-seq reads to its own genome, compared to the Vitis vinifera PN40024.V4 reference genome, thus revealing the expression levels of genes specific to Vitis champinii. Moreover, differences in coding sequences were observed in ortholog genes between Vitis champinii and Vitis vinifera, which therefore challenges previous differential expression analyses performed between contrasting Vitis genotypes on the same gene from the Vitis vinifera genome. Genes with possible implications in drought and salt tolerance have been identified across the genome of Vitis champinii, and the same genomic data can potentially guide the discovery of candidate genes specific from Vitis champinii for other traits of interest, therefore becoming a valuable resource for rootstock breeding designs, specially towards increased drought and salinity due to climate change.

Mapping and tracking canopy size with VitiCanopy

Understanding vineyard variability to target management strategies, apply inputs efficiently and deliver consistent grape quality to the winery is essential. However, despite inherent vineyard variability, the majority are managed as if they are uniform. VitiCanopy is a simple, grower-friendly tool for precision/digital viticulture that allows users to collect and interpret objective spatial information about vineyard performance. After four years of field and market research, an upgraded VitiCanopy has been created to achieve a more streamlined, technology-assisted vine monitoring tool that provides users with a set of superior new features, which could significantly improve the way users monitor their grapevines. These new features include:
• New user interface
• User authentication
• Batch analysis of multiple images
• Ease the learning curve through enhanced help features
• Reporting via the creation of colour maps that will allow users to assess the spatial differences in canopies within a vineyard.
Use-case examples are presented to demonstrate the quantification and mapping of vineyard variability through objective canopy measurements, ground-truthing of remotely sensed measurements, monitoring of crop conditions, implementation of disease and water management decisions as well as creating a history of each site to forecast quality. This intelligent tool allows users to manage grapevines and make informed management choices to achieve the desired production targets and remain profitable.

Effects of graft quality on growth and grapevine-water relations

Climate change is challenging viticulture worldwide compromising its sustainability due to warmer temperatures and the increased frequency of extreme events. Grafting Vitis vinifera L.