terclim by ICS banner
IVES 9 IVES Conference Series 9 DISCRIMINATION OF BOTRYTIS CINEREA INFECTED GRAPES USING UNTARGE-TED METABOLOMIC ANALYSIS WITH DIRECT ELECTROSPRAY IONISATION MASS SPECTROMETRY

DISCRIMINATION OF BOTRYTIS CINEREA INFECTED GRAPES USING UNTARGE-TED METABOLOMIC ANALYSIS WITH DIRECT ELECTROSPRAY IONISATION MASS SPECTROMETRY

Abstract

Infection of grapes (Vitis vinifera) by Botrytis cinerea (grey mould) is a frequent occurrence in vineyards and during prolonged wet and humid conditions can lead to significant detrimental impact on yield and overall quality. Growth of B. cinerea causes oxidisation of phenolic compounds resulting in a loss of colour and formation of a suite of off-flavours and odours in wine made from excessively infected fruit. Apart from wine grapes, developing post-harvest B. cinerea infection in high-value horticultural products during storage, shipment and marketing may cause significant loss in fresh fruits, vegetables and other crops. A rapid and sensitive assessment method to detect, screen and quantify fungal infection would greatly assist viticultural growers and winemakers in determining fruit quality.
In this study metabolites were extracted from homogenate samples using acetonitrile with the data set comprising 140 healthy and infected grapes representing different vintages, cultivars, regions and maturity stages. Sample extracts were randomly analysed by direct injection into a LTQ ion mass spectrometer, operating in negative mode, including regular quality assurance samples with data collected from 50-2000 m/z for 1 minute. Molecular feature abundances were summed between 0.1-0.4 minutes and minmax normalised prior to PCA for quality control. Samples were randomly assigned to a calibration and independent test data set, with feature reduction, a two-class model PLS-DA, cross validation and permutation testing performed with the calibration data set. Prediction of sample class in the independent test samples demonstrated an overall predictive error of less than 5%. Feature importance was assessed using a combined VIP and selectivity ratio plot which demonstrated a high level of correlation with standard volcano plots. Annotation of important molecular features was undertaken using a high resolution Orbitrap MS detector, and LCqTOF of selected samples from healthy and infected extracts.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Article

Authors

Liang Jiang1-3, Morphy C. Dumlao1,2,4, William A. Donald4, Christopher C. Steel1,3, Leigh M. Schmidtke1-3

1. Gulbali Institute, Charles Sturt University, Wagga Wagga, New South Wales, Australia 2678
2. The Australian Research Council Training Centre for Innovative Wine Production, University of Adelaide (Waite Campus), South Australia 5064
3. School of Agricultural, Environmental and Veterinary Science, Faculty of Science, Charles Sturt University, Wagga Wagga, New South Wales, Australia 2678
4. School of Chemistry, Faculty of Science, University of New South Wales (Sydney), New South Wales, Australia, 2052

Contact the author*

Keywords

Rapid analysis, metabolomics work flow, high resolution mass spectrometry, fruit quality

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

YEAST DERIVATIVE PRODUCTS: CHARACTERIZATION AND IMPACT ON RIBOFLAVIN RELEASE DURING THE ALCOHOLIC FERMENTATION

Light-struck taste (LST) is a wine fault that can occur in white and sparkling wines when exposed to light. This defect is mainly associated to the formation of methanethiol and dimethyl disulfide due to light-induced reactions involving riboflavin (RF) and methionine [1]. The presence of RF in wine is mainly due to the metabolism of yeast [2] which fermenting activity can be favoured by using yeast derivative products (YDPs) as nutrients. Nonetheless, a previous study showed the addition of YDPs before the alcoholic fermentation (AF) led to higher concentrations of RF in wines [3]. Due to the widespread use of YDPs in the winemaking process, this study aimed to understand the possible relation between the content of RF in wine and the YDP adopted as nutrient for AF.
Read More

RED WINE AGING THROUGH 1H-NMR METABOLOMICS

Premium red wines are often aged in oak barrel. This widespread winemaking process is used, among others, to provide roundness and complexity to the wine. The study of wine evolution during barrel aging is crucial to better ensure control of wine quality.
¹H-NMR has already been proved to be an efficient tool to monitor winemaking process [1]. Indeed, it is a non-destructive technique, it requires a small amount of sample and a short time of analysis, yet it provides clues about several chemical families.

Read More

LARGE-SCALE PHENOTYPIC SCREENING OF THE SPOILAGE YEAST BRETTANOMYCES BRUXELLENSIS: UNTANGLING PATTERNS OF ADAPTATION AND SELECTION, AND CONSEQUENCES FOR INNOVATIVE WINE TREATMENTS

Brettanomyces bruxellensis is considered as the main spoilage yeast in oenology. Its presence in red wine leads to off-flavour due to the production of volatile phenols such as 4-vinylphenol, 4-vinylguaiacol, 4-ethylphenol and 4-ethylguaiacol, whose aromatic notes are unpleasant (e.g. animal, leather, horse or pharmaceutical). Beside wine, B. bruxellensis is commonly isolated from beer, kombucha and bioethanol production, where its role can be described as negative or positive. Recent genomic studies unveiled the existence of various populations.

Read More

SHIRAZ FLAVONOID EXTRACTABILITY IMPACTED BY HIGH AND EXTREME HIGH TEMPERATURES

Climate change is leading to an increase in average temperature and in the severity and occurrence of heatwaves, and is already disrupting grapevine phenology. In Australia, with the evolution of the weather of grape growing regions that are already warm and hot, berry composition including flavonoids, for which biosynthesis depends on bunch microclimate, are expected to be impacted [1]. These compounds, such as anthocyanins and tannins, contribute substantially to grape and wine quality. The goal of this research was to determine how flavonoid extraction is impacted when bunches are exposed to high (>35 °C) and extreme high (>45 °C) temperatures during berry development and maturity.

Read More

INFLUENCE OF THE NITROGEN / LIPIDS RATIO OF MUSTS ON THE REVELATION OF AROMATIC COMPOUNDS IN SAUVIGNON BLANC WINE

Production of volatile compounds by yeast is known to be modulated by must nitrogen. Nevertheless, various parameter of must quality have an impact on yeast fermentation. In this study we propose to evaluate the impact of nitrogen / lipids balance on a Sauvignon Blanc grape juice (Val de Loire).
Must was prepared from the same grapes at pilot scale. Three modalities were carried out: direct pressing, direct pressing with a pre-fermentation cold stabulation and pellicular maceration before pressing.

Read More