OENO IVAS 2019 banner
IVES 9 IVES Conference Series 9 OENO IVAS 9 OENO IVAS 2019 9 Chemical and Biochemical reactions, including grape and wines microorganisms impact 9 Oenological tannins to prevent Botrytis cinerea damage: reduction of laccase activity

Oenological tannins to prevent Botrytis cinerea damage: reduction of laccase activity

Abstract

Oenological tannins are classified as hydrolysable and condensed tannins. Their use in winemaking is only authorized, to facilitate wine fining. Nevertheless, tannins could also be used to prevent laccase effects. 

Indeed, our group has recently proved their effects against laccase damage [1]. The goal of this study was to better understand the mechanism of action of oenological tannins on laccase activity induced by Botrytis cinerea. Five oenological tannins were used (gallotannin, ellagitannin, quebracho, grape-skin and grape-seed) and compared with ascorbic acid (AA) and sulfur dioxide (SO2). Oenological tannins, AA and SO2 were added to botrytized must at different doses. After 4 minutes, laccase activity was measured by the syringaldazine method [2] using different concentration of subtract. Enzymatic kinetic constants (Km/Vmax) were determined according to Michaelis-Menten model. Furthermore, B. cinerea (strain 213) was grown in a stimulating liquid medium for laccase production [3]. The molecular weight (MW) and the effect of bentonite and tannins upon laccase were studied by SDS-PAGE. The results confirm that all oenological tannins inhibit laccase activity and that the higher the dose the lower the laccase activity. In this way, gallotannin, grape-seed and skins tannins seem to be the most effective tannins. All the tannins were as effective as AA, even though SO2 was clearly the most effective inhibitor. The laccase produced by B. cinerea had a MW of 95 kDa. After bentonite treatment all wine protein bands disappeared and laccase band decreased slightly although its activity remains stable. The interaction between different oenological tannins and laccase was analyzed by measuring the reduction of the intensity of the laccase band. In general, the reduction of band intensity correlates with the reduction of laccase enzymatic activity. 

It can be concluded therefore that oenological tannins a good candidate to prevent laccase effects, helping to diminish the SO2 dose in grapes infected by B. cinerea. 

[1] Vignault, A.; Pascual, O.; Jourdes, M.; Moine, V.; Fermaud, M.; Roudet, J.; Canals, J.M.; Teissedre, P-L.; Zamora, F. Oeno One, 2019. 
[2] Urbano Cuadrado, M.; Pérez-Juan, P.M.; Luque de Castro, M.; Gomez-Nieto, M.A., Anal Chim Acta, 2005, 553, 99-104. 
[3] Quijada-Morin, N.; Garcia, F.; Lambert, K.; Walker, A.S.; Tiers, L.; Viaud, M.; Sauvage, F-X.; Hirtz, C.; Saucier, C.; Aust J Grape Wine Res, 2018, 24, 241-251.

DOI:

Publication date: June 19, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Fernando Zamora (1), Adeline Vignault (2), Jordi Gombau (1), Michael Jourdes (2), Virginie Moine (3), Joan Miquel Canals (1), Pierre-Louis Teissedre (2)

1) Departament de Bioquímica i Biotecnologia. Facultat d’Enologia. Universitat Rovira i Virgili. C/ Marcel.lí Domingo 1, 43007-Tarragona (Spain)
2) Unitéde recherche Oenologie, EA 4577, USC 1366 INRA, ISVV, Universitéde Bordeaux, Bordeaux INP, F33882 Villenave d’Ornon France
3) Laffort, 11 rue Aristide berges, 33270 Floirac, France

Contact the author

Keywords

Oenological tannins, Botrytis cinerea laccase, Kinetics, SDS-PAGE 

Tags

IVES Conference Series | OENO IVAS 2019

Citation

Related articles…

Co-design and evaluation of spatially explicit strategies of adaptation to climate change in a Mediterranean watershed

Climate change challenges differently wine growing systems, depending on their biophysical, sociological and economic features. Therefore, there is a need to locally design and evaluate adaptation strategies combining several technical options, and considering the local opportunities and constraints (e.g. water access, wine typicity). The case study took place in a typical and heterogeneous Mediterranean vineyard of 1,500 ha in the South of France. We developed a participatory modeling approach to (1) conceptualize local climate change issues and design spatially explicit adaptation strategies with stakeholders, (2) numerically evaluate their effects on phenology, yield and irrigation needs under the high-emissions climate change scenario RCP 8.5, and (3) collectively discuss simulation results. We organized five sets of workshops, with in-between modeling phases. A process-based model was developed that allowed to evaluate the effects of six technical options (late varieties, irrigation, water saving by reducing canopy size, adjusting cover cropping, reducing density, and shading) with various distributions in the watershed, as well as vineyard relocation. Overall, we co-designed three adaptation strategies. Delay harvest strategy with late varieties showed little effects on decreasing air temperature during ripening. Water constraint limitation strategy would compensate for production losses if disruptive adaptations (e.g. reduced density) were adopted, and more land got access to irrigation. Relocation strategy would foster high premium wine production in the constrained mountainous areas where grapevine is less impacted by climate change. This research shows that a spatial distribution of technical changes gives room for adaptation to climate change, and that the collaboration with local stakeholders is a key to the identification of relevant adaptation. Further research should explore the potential of adaptation strategies based on soil quality improvement and on water stress tolerant varieties.

Vineyards and clay minerals: multi-technique analytical approach and correlations with soil properties

Purpose of this research is to quantitatively assess the mineral component of vineyard soils, with particular attention to the mineralogical analysis of clays, which represent an element of high importance in the vineyard culture as well as in general agriculture. An X-ray diffraction (XRD) / thermogravimetric (TG) multi-technique analytical approach was developed, tested on soil samples taken from vineyards around the world. This codified analytical procedure was necessary to obtain precise qualitative and quantitative mineralogical data, globally comparable to distinguish the geopedological identity of the vineyards. Soil samples from vineyards of various locations were analysed, in very different geological conditions. The bulk-rock quantitative phase analysis (QPA) was obtained by the Rietveld method while the detailed composition of the clay-sized fraction was determined by modelling of the oriented X-ray diffraction patterns. The research provided a precise classification of the mineral component of soils, distinguishing the mineral phases of the clays and the so-called mixed-layer clay minerals. We found that the content in mixed layers can be directly correlated with the water retention and the cation exchange capacity ​​of the soil, while the presence of other clayey minerals and phyllosilicates in this research did not affect this CEC parameter, which codes the fertility level of the soils. The study demonstrates that terroir, in particular soils formed in complex or very different geological conditions, can only be effectively interpreted by properly analysing its mineral phases, in particular the mixed-layer clay component. These are characteristic abiotic ecological indicators, which may have specific eco-physiological influences on the plant.

Climate, Viticulture, and Wine … my how things have changed!

The planet is warmer than at any time in our recorded past and increasing greenhouse emissions and persistence in the climate system means that continued warming is highly likely. Climate change has already altered the basic framework of growing grapes for wine production worldwide and will likely continue to do so for years to come. The wine sector can continue to play an important role in leading the agricultural sector in addressing climate change. From developing on…

austrianvineyards.com: online viewer of all designations of Austrian wine

To digitally record and present all the origins of Austrian wines in the same perfect and clear way was the motivation for the Austrian Wine Marketing Board (Austrian Wine) to start with the project in 2018. In June 2021 the results were presented to the public in an online viewer showing all the designations of Austrian wine, available at https://austrianvineyards.com in a largely barrier-free manner. The online viewer provides tailored individual maps fitted to the respective zoom level. The smallest unit of wine-origins in Austria is called Ried and is displayed in a plot-specific manner highlighting areas under vine. Information on the Ried include administrative district, winegrowing municipality, cadastral municipality, large collective vineyard site, specific winegrowing region, generic winegrowing region, winegrowing area and, in many cases, an illustrative picture. Complementary data on the size, elevation (minimum-maximum), orientation (in 8 sectors plus flat) and gradient (minimum, maximum, average) are based on the area under vine according to the EU’s Integrated Administration and Control System. Additional information covers climate data. The diagrams are taken from the monthly breakdown of data in the annals of the Central Institute for Meteorology and Geodynamics, Austria provide a display of values for air temperature, precipitation, and sunshine hours for the reference year and the long-term average. Seasonal aggregated data on temperature, precipitation, and sunshine hours complete the display. Short descriptions with emphasis on geology and soil, field name in historical maps, etymology of the denomination, and main planted variety complements the available information for the main designations in the online viewer. These descriptions are compiled by winegrowers, geologists, historians, and journalists. All the information and data can be extracted to a pdf-file. Printed vineyard maps are also available. Missing content regarding wine origins in Styria will be completed in winter 2021/22.

Towards adaptation to climate change in Rioja: Quality evaluation of wines obtained from Grenache x Tempranillo selections

The wine sector is of great relevance and tradition in Mediterranean countries, however, it may be most susceptible to climate change. In recent years, wine production is facing changes worldwide, both at environmental as well as commercial levels, due to global warming and the shift in consumers’ preferences. Wine growers and wine makers are in search of solutions that allow to face these new challenges. One of the most promising initiatives in the long term is the introduction of new plant materials, specifically intraspecific hybridizations between premium varieties that may improve traditional germplasm in its adaptation to climate change. These inter-varietal crosses have the potential to generate quality wines, whilst maintaining the regional typicity, and constitute an attractive alternative for the consumer due to their sensory attributes. In this study, we have evaluated wines from 29 intraspecific Garnacha x Tempranillo hybrids in two different locations, with the aim to assess their oenological potential and sensory attributes. Thirteen of the selections were white and 16 were red. Microvinifications were conducted with two or three replications depending on grape availability. Conventional oenological parameters were determined for all wines. The sensory evaluation and hedonic scores were given by five experts. Red selections obtained higher quality scores than white ones. Among the white selections with higher quality scores, GT-41 Varea and GT-159 Varea outstand, due to their high total acidity and high malic acid content. Regarding red selections, GT-57 Varea and GT-57 UR were perceived as higher in quality, highlighted for their moderate alcoholic and high anthocyanin content. Our results indicate that intraspecific hybridization may be a powerful tool for adapting traditional cultivars to climate change in Rioja.