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…

USE OF COLD LIQUID STABULATION AS AN OENOLOGICAL TECHNIQUE IN WHITE WINEMAKING: EFFECTS ON PHENOLIC, AROMATIC AND SENSORIAL COMPOSITION

The application of different winemaking techniques helps to modify the basic parameters, phenolic profile, and aroma components influencing the final wine quality. In particular, pre-fermentative processes aim to increase the extraction and preservation of grape native compounds. Among them, cold liquid stabulation (macération sur bourbes) consists in maintaining the grape juice on its lees, in suspended condition at low temperature (0-8 °C) for a variable time (generally from 7 to 21 days). The aim of this work is to apply the cold liquid stabulation on two Italian white grape varieties, Arneis and Cortese, to evaluate the impact on basic parameters, color, polyphenolic compounds (TPI), antioxidant power (DPPH), total polysaccharides, and free and glycosylated volatile compounds (GC-MS analysis) during and after the process.
Read More

NEW METHOD FOR THE QUANTIFICATION OF CONDENSED TANNINS AND OTHER WINE PHENOLIC COMPOUNDS USING THE AUTOMATED BIOSYSTEMS SPICA ANALIZER

Wine phenolic compounds are important secondary metabolites in enology due to their antioxidant and nutraceutical properties, and their role in the development of color, taste, and protection of wine from oxidation and spoilage. Tannins are valuable phenolic compounds that contribute significantly to these wine properties, especially in mouthfeel characteristics; however, tannin determination remains a significant challenge, with manual and time-consuming methods or complex methodologies. The purpose of this study is to propose a novel method for quantifying condensed tannins in finished wine products.

Read More

IMPACT OF METSCHNIKOWIA PULCHERRIMA DURING FERMENTATION ON AROMATIC PROFILE OF VIDAL BLANC ICEWINE

Non-Saccharomyces yeasts not only increase microbial diversity during wine fermentation, but also have a positive effect on improving wine aroma. Among these non-Saccharomyces yeast species, Metschnikowia pulcherrima is often studied and used in winemaking in recent years, but its application in icewine has been rarely reported. In this study, indigenous M. pulcherrima strains and Saccharomyces cerevisiae strains (commercial and indigenous strains) were sequentially inoculated for icewine fermentations; meanwhile, pure S. cerevisiae fermentations were used as the control; indigenous strains used above were screened from spontaneous fermentations of Vidal blanc icewine.

Read More

FOLIAR APPLICATION OF METHYL JASMONATE AND METHYL JASMONATE PLUSUREA: INFLUENCE ON PHENOLIC, AROMATIC AND NITROGEN COMPOSITION OFTEMPRANILLO WINES

Phenolic, volatile and nitrogen compounds are key to wine quality. On one hand, phenolic compounds are related to wine color, mouthfeel properties, ageing potential. and are associated with beneficial health properties. On the other hand, wine aroma is influenced by hundreds of volatile compounds. Fermentative aromas represent, quantitatively, the wine aroma, and among these volatile compounds, esters, higher alcohols and acids are mainly responsible for the fermentation bouquet.

Read More

Molecular approaches for understanding and modulating wine taste

Wine consumers generally demand wines having a perception of softer tannins and less ripe, having a heaviness and richness on palate (full-body wine) with a limpid and stable color. However, polyphenol
(tannins)-rich wines have been also correlated with unpleasant taste properties such as astringency and
bitterness when perceived at high intensities. Modulating these unpleasant properties could be important for consumer’s approval of wines.

Read More