Terroir 2020 banner
IVES 9 IVES Conference Series 9 Application of fluorescence spectroscopy with multivariate analysis for authentication of Shiraz wines from different regions

Application of fluorescence spectroscopy with multivariate analysis for authentication of Shiraz wines from different regions

Abstract

Aim: To investigate the possibility of utilising simultaneous measurements of absorbance-transmittance and fluorescence excitation-emission matrix (A-TEEM) combined with chemometrics, as a robust method that gives rapid results for classification of wines from different regions of South Australia according to their Geographical Indication (GI), and to gain insight into the effect of terroir on inter regional variation.

Methods and Results: Additionally, to obtaining various colour parameters, the A-TEEM technique enables the “fingerprint” of wine samples to be attained in response to the presence of fluorophoric compounds. This is accomplished by recording a three-dimensional excitation-emission matrix (EEM) over multiple excitation and emission wavelengths, which can then be analysed using multivariate statistical modelling to classify wines. Shiraz wine samples (n = 134) from six different GIs of South Australia (Barossa Valley, Clare Valley, Eden Valley, Langhorne Creek, McLaren Vale, and Riverland) were analysed and absorbance spectra, hue, intensity, CIE L*a*b, CIE 1931, and EEMs were recorded for each sample. EEM data were evaluated according to the cross-validation model built with extreme gradient boost discriminant analysis (XGBDA) using score probability to assess the accuracy of classification according to the region of origin. Preliminary results have shown a high prediction ability and the data extracted from A-TEEM could be used to investigate phenolics as potential chemical markers that may provide effective regional discrimination.

Conclusions: 

The molecular fingerprinting capability and sensitivity of EEM in conjunction with multivariate statistical analysis of the fluorescence data using the XGBDA algorithm provided sufficient chemical/spectral information to facilitate accurate classification of Shiraz wines according to the region of origin. A-TEEM coupled with XGBDA modelling appears to be a promising tool for wine authentication according to its geographical origin.

Significance and Impact of the Study: Having tangible evidence that Australian fine wines may be discriminated on the basis of geographical origin, will help to improve the international reputation of Australian wines and increase global competitiveness. Understanding of the important regional chemical parameters would allow grape growers and winemakers to optimise their viticultural and winemaking practices to preserve these characteristics of their terroir. Moreover, verifying the content in the bottle according to the label descriptions with a rapid method, has the potential to verify product provenance and counteract fraud in cases where wine of inferior/questionable quality or contaminated wine is presented as originating from Australia.

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type : Video

Authors

R.K.R. Ranaweeraa, A. M. Gilmoreb, D.L. Caponea, c, S.E.P. Bastiana,c, D.W Jefferya, c*

aDepartment of Wine and Food Science, The University of Adelaide, South Australia, Australia
bHORIBA Instruments Inc., 20 Knightsbridge Rd., Piscataway, NJ 08854, United States
cAustralian Research Council Training Centre for Innovative Wine Production, The University of Adelaide

Contact the author

Keywords

Geographical origin, chemometrics, modelling, excitation-emission matrix

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Biodiversity in the vineyard agroecosystem: exploring systemic approaches

Biodiversity conservation and restoration are essential for guarantee the provision of ecosystem services associated to vineyard agroecosystem such as climate regulation trough carbon sequestration and control of pests and diseases. Most of published research dealing with the complexity of the vineyard agroecosystems emphasizes the necessity of innovative approaches, including the integration of information at different temporal and spatial scales and development of systemic analysis based on modelling. A biodiversity survey was conducted in the Franciacorta wine-growing area (Lombardy, Italy), one of the most important Italian wine-growing regions for sparkling wine production, considering a portion of the territory of 112 ha. The area was divided into several Environmental Units (EUs), defined as a whole vineyard or portion of vineyard homogenous in terms of four agronomic characteristics: planting year, planting density, cultivar, and training system. In each EU a set of compartments was identified and characterised by specific variables. The compartments are meteorology, morphology (altitude, slope, aspect, row orientation, and solar irradiance), ecological infrastructures and management. The landscape surrounding EU was also characterised in terms of land-use in a buffer zone of 500 m. For each component a specific methodology was identified and applied. Different statistical approaches were used to evaluate the method to integrate the information related to different compartments within the EU and related to the buffer zone. These approaches were also preliminarily evaluated for their ability to describe the contribution of biodiversity and landscape components to ecosystem services. This methodological exploration provides useful indication for the development of a fully systemic approach to structural and functional biodiversity in vineyard agroecosystems, contributing to promote a multifunctional perspective for the all wine-growing sector.

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)

Exploring resilience and competitiveness of wine estates in Languedoc-Roussillon in the recent past: a multi-level perspective

The Languedoc-Roussillon wineries are facing a decline in wine yields particularly PGI yields due to many factors. Climate change is just ones, but is expected to increase in the future. There is also structurally a large heterogeneity of yield profiles among terroirs, varieties and strategies. This work investigates the link between yield, competitiveness and resilience to explore how resilient winegrowers have been in the recent past. To this end two approaches have been combined; (i) an accountancy database analysis at estate scale and (ii) municipality level competitiveness analysis. A new resilience indicator that characterizes the capacity of an estate to absorb yield variation is also defined. The FADN database between 2000 and 2018 of ex-Languedoc-Roussillon (France) and other data are used to analyse the current situation and the past evolution of competitiveness and resilience by type of estate (type of farm: PGI and/or PDO & type of commercialization: bulk and/or bottles). The net margin, which defines competitiveness, is not correlated to yield for all types but depends on the type of commercialization and the level of specialisation. The resilience indicator shows that the net margin of estates specialized in PGI is particularly sensitive to yield declines. We also show that price evolutions seem to compensate the effect of yield losses for the majority of types. Municipality scale analysis shows the links between local pedoclimate, yield, commercialization strategies and price. Overlapping a PDO with a PGI does not always increase a municipality’s PGI competitiveness. It is difficult to make links between causes and effects due to the complexity of the wine production system. Production diversification may be a solution. Resorting to the two level of analysis helps resolving the data gap that is necessary to explore the links between yield and economic performance of the wine estates in the long term.

A predictive model of spatial Eca variability in the vineyard to support the monitoring of plant status

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Influence of a spontaneous cover crop on the vineyard and soil erosion under Mediterranean climate

Sixty five % of the agricultural area of the Basque Country located in the DO Ca Rioja corresponds to vineyards. More than 40% of it has an average slope greater than 10%, which makes it sensitive to erosive processes. Furthermore, it is foreseeable that extreme weather events (storms, hail, extreme heat and cold, etc.) will be favored due to climate change. Cover cropping can mitigate this risk, and therefore the objective of this work is to evaluate the impact that a vegetable cover has on the agronomic behavior of the vineyard, the quality of the grape and soil erosion. For this, a trial has been carried out with a Graciano variety vineyard with a slope between 10% -20% during the years 2020 and 2021. Conventional tillage management in the area has been compared (4-6 passes per year of tillage machinery) versus spontaneous vegetation cover management in the vineyard. This implies not tilling and allowing the grass of the land to colonize the range between the lines of vines, controlling their height through 1-3 mowing passes per year, always trying to affect the surface of the land as little as possible. The vegetative growth, yield and quality of the grape and wine was measured. Furthermore, erosion has been measured using Gerlasch boxes. The yield was lower in the second year of the trial in the cover crop treatment, but erosion was significantly reduced.