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…

Downscaling of remote sensing time series: thermal zone classification approach in Gironde region

In viticulture, the challenges of local climate modelling are multiple: taking into account the local environment, fine temporal and spatial scales, reliable time series of climate data, ease of implementation and reproducibility of the method. At the local scale, recent studies have demonstrated the contribution of spatialization methods for ground-based climate observation data considering topographic factors such as altitude, slope, aspect, and geographic coordinates (Le Roux et al, 2017; De Rességuier et al, 2020). However, these studies have shown questions in terms of the reproducibility and sustainability of this type of climate study. In this context, we evaluated the potential of MODIS thermal satellite images validated with ground-based climate data (Morin et al, 2020). Previous studies have been encouraging, but questions remain to be explored at the regional scale, particularly in the dynamics of the massive use of bioclimatic indices to classify the climate of wine regions. The results at the local scale were encouraging, but this approach was tested in the current study at the regional scale. Several objectives were set: 1) to evaluate the downscaling method for land surface temperature time series, 2) to identify regional thermal structure variations. We used weekly minimum and maximum surface temperature time series acquired by MODIS satellites at a spatial resolution of 1000 m and downscaled at 500 m using topographical variables. Two types of analyses were performed:

Bioclimatic shifts and land use options for Viticulture in Portugal

Land use, plays a relevant role in the climatic system. It endows means for agriculture practices thus contributing to the food supply. Since climate and land are closely intertwined through multiple interface processes, climate change may lead to significant impacts in land use. In this study, 1-km observational gridded datasets are used to assess changes in the Köppen–Geiger and Worldwide Bioclimatic (WBCS)

Assessment of the impact of actions in the vineyard and its surrounding environment on biodiversity in Rioja Alavesa (Spain)

Traditional viticulture areas have experienced in the last decades an intensification of field practices, linked to an increased use of fertilisers and phytosanitary products, and to a more intensive mechanization and uniformization of the landscape. This change in management has sometimes led to higher rates of soil erosion andloss of soil structure, fertility decline, groundwater contamination, and to an increased pressure of pests and diseases. Additionally, intensification usually leads to a simplification of landscapes, of particular concern in prestigious wine grape regions where the economical revenue encourages the conversion of land use from natural habitats to high value wine grape production. To revert this trend, it is necessary that growers implement actions that promote biodiversity in their vineyards. The aim of this study is to assess the impact of the implementation of cover crops, vegetational corridors, dry stone walls and vineyard biodiversity hotspots estimated through the study of arthropods. The work has been carried out in four vineyards in Rioja Alavesa belonging to Ostatu winery, where these infrastructures were implemented in 2020. The presence and diversity of arthropods was studied by capturing them at different times in the season and at different distances from the infrastructure using pit-fall traps in the soil and yellow, white and blue chromatic traps at the canopy level. This is a preliminary study in which all adult insects were sorted to the taxonomic level of order and Coleoptera were classified to morphospecies. The results obtained show that there is a relationship between the basic characteristics of the vineyard and the arthropods captured, with a positive effect, although also dependent on the vineyard, of the presence of infrastructure.

How does aromatic composition of red wines, resulting from varieties adapted to climate change, modulate fruity aroma?

One of the major issues for the wine sector is the impact of climate change linked to the increasing temperatures which affects physicochemical parameters of the grape varieties planted in Bordeaux vineyard and consequently, the quality of wine. In some varietals, the attenuation of their fresh fruity character is accompanied by the accentuation of dried-fruit notes [1]. As a new adaptive strategy on climate change, some winegrowers have initiated changes in the Bordeaux blend of vine varieties [2]. This study intends to explore the fruitiness in wines produced from grape varieties adapted to the future climate of Bordeaux. 10 commercial single–varietal wines from 2018 vintage made from the main grape varieties in the Bordeaux region (Cabernet franc, Cabernet-Sauvignon and Merlot) as well as from indigenous grape varieties from the Mediterranean basin, such as Cyprus (Yiannoudin), France (Syrah), Greece (Agiorgitiko and Xinomavro), Portugal (Touriga Nacional) and Spain (Garnacha and Tempranillo), were selected among 19 samples using sensory descriptive analyses. Both sensory and instrumental analyses were coupled, to investigate their fruity aroma expression. For sensory analysis, samples were prepared from wine, using a semi preparative HPLC method which preserves wine aroma and isolates fruity characteristics in 25 specific fractions [3,4]. Fractions of interest with intense fruity aromas were sensorially selected for each wine by a trained panel and mixed with ethanol and microfiltered water to obtain fruity aromatic reconstitutions (FAR) [5]. A free sorting task was applied to categorize FAR according to their similarities or dissimilarities, and different clusters were highlighted. Instrumental analysis of the different FAR and wines demonstrated variations in their molecular composition. Results obtained from sensory and gas chromatography analysis enrich the knowledge of the fruity expression of red wines from “new” grape varieties opening up new perspectives in wine technology, including blending, thus providing new tools for producers.

Long-term drought resilience of traditional red grapevine varieties from a semi-arid region

In recent decades, the scarcity of water resources in agriculture in certain areas has been aggravated by climate change, which has caused an increase in temperatures, changes in rainfall patterns, as well as an increase in the frequency of extreme phenomena such as droughts and heat waves. Although the vine is considered a drought-tolerant specie, it has to satisfy important water requirements to complete its cycle, which coincides with the hottest and driest months. Achieving sustainable viticulture in this scenario requires high levels of efficiency in the use of water, a scarce resource whose use is expected to be severely restricted in the near future. In this regard, the use of drought-tolerant varieties that are able to maintain grape yield and quality could be an effective strategy to face this change. During three consecutive seasons (2018-2020) the behavior in rainfed regime of 13 traditional red grapevine varieties of the Spain central region was studied. These varieties were cultivated in a collection at Centro de Investigación de la Vid y el Vino de Castilla-La Mancha (IVICAM-IRIAF) located in Tomelloso (Castilla-La Mancha, Spain). Yield components (yield, mean bunch and berry weight, pruning weight), physicochemical parameters of the musts (brix degree, total acidity, pH) and some physiological parameters related with water stress during ripening period (δ13C, δ18O) were analysed. The application of different statistical techniques to the results showed the existence of significant differences between varieties in their response to stressful conditions. A few varieties highlighted for their high ability to adapt to drought, being able to maintain high yields due to their efficiency in the use of water. In addition, it was possible quantify to what extent climate can be a determinant in the δ18O of musts under severe water stress conditions.