terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Metabolomic profiling of botrytized grape berries: unravelling the dynamic chemical transformations during noble rot

Metabolomic profiling of botrytized grape berries: unravelling the dynamic chemical transformations during noble rot

Abstract

Botrytis cinerea, a fungal pathogen commonly known as grey mold, which under specific climatic conditions can develop into a desirable form known as noble rot. In this process the fungus penetrates the grape skin, allowing water evaporation and concentration of sugars and flavors, while profoundly affects the metabolite composition of grapes, leading to the production of unique and desirable compounds in the resulting wines. The result is a unique and complex wine with a luscious sweetness, heightened aromatics, and a distinct character. This study aimed to explore the metabolite profiles and chemical transformations associated with noble rot in grape berries from the Betsek area in the Tokaj region. Botrytized grape samples were collected monthly from August to November, covering six phases of botritization. Immediate freezing in liquid nitrogen was performed on-field to preserve sample integrity. Metabolomic analysis was conducted by cryomilling the samples, followed by extraction with methanol and ethyl acetate. The extracts were analyzed using liquid chromatography coupled with quadrupole time-of-flight mass spectrometry, utilizing both positive and negative electrospray ionization. The resulting metabolomic data was processed and statistically analyzed. A principal component analysis (PCA) was performed on the untargeted metabolomic profiles obtained from the botrytized grape samples, which revealed distinct differences between each phase of botritization. The main source of variance observed in the PCA plot was attributed to the botrytization process itself. This finding suggests that the metabolic changes occurring during the different stages of botritization significantly contribute to the overall metabolite composition of the grape berries. Results provided a valuable overview of the dynamic nature of the metabolic transformations associated with noble rot, highlighting the temporal evolution of the metabolite profiles throughout the botrytization process. Further analysis will enable the identification of specific metabolites that contribute to the unique chemical characteristics of noble rot-affected grape berries.

Acknowledgements: This research was funded by the National Research, Development and Innovation Office under the project titled “Research and development to improve sustainability and climate resilience of viticulture and oenology at the Eszterházy Károly Catholic University” with the grant number TKP2021-NKTA-16.

DOI:

Publication date: October 10, 2023

Issue: ICGWS 2023

Type: Poster

Authors

Miklós Lovas1*, Marietta Korózs1, Anna Molnár1, Ádám Hegyi1, Kriszta Szabadi1, Thomas Cels1, Kálmán Zoltán Váczy1

1Research and Development Centre, Eszterházy Károly Catholic University, Eger, Hungary

Contact the author*

Keywords

noble rot, botrytis, metabolomics, grape, LCMS

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Effect of pH and ethanol on Lactiplantibacillus plantarum in red must fermentation: potential use of wine lees

Wine is the result of the alcoholic fermentation (AF) of grape must. Besides AF, wine can also undergo the malolactic fermentation (MLF) driven out by lactic acid bacteria (LAB). Among LAB, Oenococcus oeni and Lactiplantibacillus plantarum are the dominant species in wine. Even if O. oeni is the most common LAB undergoing MLF in wine, due to its high tolerance to wine conditions, L. plantarum can be used to undergo MLF in must. The moderate tolerance of L. plantarum to low pH and ethanol, may compromise the fermentative process in harsh wines.

Sustainable management of grapevine trunk diseases

Grapevine trunk diseases (GTD) occur wherever grapes are grown and are considered the main biotic factor reducing yields and shortening vineyards’ lifespan. Currently, no product is available to eradicate GTD once grapevines are infected. Therefore, prophylactic strategies based on pruning wound protection and ‘remedial surgery’, the only eradication method based on the elimination of infected wood and renewal of the vine by means of new canes or suckers, are the only effective strategies available. The Canadian grape and wine industry focusses on a sustainable production and thus, looking for alternatives to chemicals for disease management is a top priority.

Adsorption of tetraconazole by organic residues and vineyard organically-amended soils 

Spain is the country with the largest wine-producing area in the EU and its productivity is largely controlled applying fungicides. However, residues of these compounds can move and contaminate surface and groundwater. The objective of this work was to evaluate the capacity of bioadsorbents from different origin to adsorb and immobilize tetraconazole by themselves or when applied as organic soil amendment, and to prevent soil and water contamination by this fungicide. The adsorption of tetraconazole by 3 organic residues: spent mushroom substrate (SMS), green compost (GC) and vine pruning sawdust (VP), as well as by vineyard soils unamended and amended individually with these residues at 1.5% (w/w) was evaluated using the batch equilibrium technique.

Detoxification capacities of heavy metals and pesticides by yeasts 

Winegrowing is still characterized by the extensive use of chemical fertilizers and plant protection products, despite strong recommendations to limit these practices. A part of these xenobiotics and metals are then found in grape juice and wine, causing a major health concern, as well as negatively affecting the fermentation process. In recent years, there has been renewed interest in non-Saccharomyces yeasts. These species have a wide phenotypic diversity, which would be exploited to broaden the aromatic palette of wines.

Distribution and sensory impact of new oak wood-derived compounds in wines

Despite the numerous research studies carried out in recent years, the study of wine aroma remains of great interest due to its complexity. Wine maturation in oak barrels is described as an important step in the production of quality wines. In fact, oak wood develops several aromatic nuances through its toasting which can be released into the wine. A great deal of work has been performed in order to identify the wood-derived volatile compounds that contribute to wine aroma (e.g., whisky-lactone, maltol, eugenol, guaiacol, vanillin).