OENO IVAS 2019 banner
IVES 9 IVES Conference Series 9 OENO IVAS 9 OENO IVAS 2019 9 Analytical tools using electromagnetic spectroscopy techniques (IR, fluorescence, Raman) 9 Multivariate characterization of Italian monovarietal red wines using FTIR spectroscopy

Multivariate characterization of Italian monovarietal red wines using FTIR spectroscopy

Abstract

The assessment of wine authenticity is of great importance for consumers, producers and regulatory agencies to guarantee the geographical origin of wines and grape variety as well. Since mid-infrared (MIR) spectroscopy with chemometrics represent a suitable tool to ascertain the wine composition, including features associated with the polyphenolic compounds, the aim of this study was to generate MIR spectra of red wines to be exploited for classification of red wines based on the relationship between grape variety and wine composition. Several multivariate data analyses were used, including Principal Component Analysis (PCA), Discriminant Analysis (DA), Support Vector Machine (SVM), and Soft Intelligent Modelling of Class Analogy (SIMCA).

The aim of this study was to investigate the application of MIR spectroscopy (from 4000 to 700 cm-1) combined with multivariate analysis to provide a rapid screening tool for discriminating among different red monovarietal Italian wine varieties.

A total of 110 monovarietal red wines vintage 2016 were collected directly from the companies across different regions of Italy, including the following eleven grape varieties: Sangiovese, Nebbiolo, Aglianico, Nerello Mascalese, Primitivo, Raboso, Cannonau, Teroldego, Sagrantino, Montepulciano and Corvina.

PCA showed five wavelengths that mainly contributed to the PC1, including much-closed peak at 1043 cm-1 that correspond to the C–O stretch absorption bands that are important regions for glycerol, whereas the ethanol peaks at about 1085 cm-1. The band at 877 cm-1 would be related to C-C stretching vibration of organic molecules, whereas the asymmetric stretching for C–O in aromatic –OH group of polyphenols within the spectral regions from 1050 to 1165 cm-1. In particular, the (1175) – 1100 – 1060 cm-1 vibrational bands are combination bands involving C–O stretching and O-H deformation of phenolic rings. The 1166-1168 cm-1 peaks are attributable to in-plane bending deformations of C-H and C–O groups of polyphenols, respectively, which polymerization may cause a slight peak shift due to the formation of H-bridges.

The best results were obtained with the SVM that achieved an overall correct classification up to 72.2 % for test set, and 44.4 % for the validation set of wines, respectively. The Sangiovese wines (n=19) were splitted in two sub-groups (Sang-Romagna n=12; Sang-Tuscany n=7) considering the indeterminacy of its origins, disputed between Romagna and Tuscany. Although the classification of three grape varieties was problematic (i.e. Nerello Mascalese, Raboso and Primitivo), the remaining wines were almost correctly assigned to their actual classes.

Conclusion:

In conclusion, MIR spectroscopy coupled with chemometrics represents an interesting approach for the classification of monovarietal red wines, which is important in quality control and authenticity monitoring.

DOI:

Publication date: June 23, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Giuseppina Paola Parpinello, Andrea Versari, Arianna Ricci, Panagiotis Arapitsas, Andrea Curioni, Luigi Moio, Susanna Rio Segade, Maurizio Ugliano

Department of Agricultural and Food Sciences, University of Bologna, (Italy) 
Fondazione Edmund Mach, Research and Innovation Centre, Department of Food Quality and Nutrition, San Michele all’Adige, (Italy) 
Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, (Italy) 
Department of Agricultural Sciences, Division of Vine and Wine Sciences, University of Naples Federico II, Avellino, (Italy) 
Dipartimento di Scienze Agrarie, Forestali e Alimentari, Universitàdegli Studi di Torino, (Italy) 
Department of Biotechnology, University of Verona, (Italy) 

Contact the author

Keywords

authenticity, FTIR, tannins, red wine

Tags

IVES Conference Series | OENO IVAS 2019

Citation

Related articles…

Mapping and tracking canopy size with VitiCanopy

Understanding vineyard variability to target management strategies, apply inputs efficiently and deliver consistent grape quality to the winery is essential. However, despite inherent vineyard variability, the majority are managed as if they are uniform. VitiCanopy is a simple, grower-friendly tool for precision/digital viticulture that allows users to collect and interpret objective spatial information about vineyard performance. After four years of field and market research, an upgraded VitiCanopy has been created to achieve a more streamlined, technology-assisted vine monitoring tool that provides users with a set of superior new features, which could significantly improve the way users monitor their grapevines. These new features include:
• New user interface
• User authentication
• Batch analysis of multiple images
• Ease the learning curve through enhanced help features
• Reporting via the creation of colour maps that will allow users to assess the spatial differences in canopies within a vineyard.
Use-case examples are presented to demonstrate the quantification and mapping of vineyard variability through objective canopy measurements, ground-truthing of remotely sensed measurements, monitoring of crop conditions, implementation of disease and water management decisions as well as creating a history of each site to forecast quality. This intelligent tool allows users to manage grapevines and make informed management choices to achieve the desired production targets and remain profitable.

Influence of weather and climatic conditions on the viticultural production in Croatia

The research includes an analysis of the impact of weather conditions on phenological development of the vine and grape quality, through monitoring of four experimental cultivars (Chardonnay, Graševina, Merlot and Plavac mali) over two production years. In each experimental vineyard, which were evenly distributed throughout the regions of Slavonia and The Croatian Danube, Croatian Uplands,

Measurement of redox potential as a new analytical winegrowing tool

Excell laboratory has initiated the development of an analytical method based on electrochemistry to evaluate the ability of wines to undergo or resist to oxidative phenomena. Electrochemistry is a powerful tool to probe reactions involving electron transfers and offers possibility of real-time measurements. In that context, the laboratory has implemented electrochemical analysis to assess oxidation state of different wine matrices but also in order to evaluate oxidative or reduced character of leaf and soil. Initially, our laboratory focused on dosage of compounds involved in responses of plant stresses and we were also interested in microbiological activity of soils. These analyses were compared with the measurement of redox potential (Eh) and pH which are two fundamental variables involved in the modulation of plant metabolism. Indeed, the variation of redox states of the plant reflects its biological activity but also its capacity to absorb nutriments. The Eh-pH conditions mainly determine metabolic processes involved in soil and leaf and our goal is to determine if this combined analytical approach will be sufficiently precise to detect biological evolutions (plant health, parasitic attack…).

Ecophysiological performance of Vitis rootstocks under water stress

The use of rootstocks tolerant to soil water deficit is an interesting strategy to cope with limited water availability. Currently, several nurseries are breeding new genotypes, but the physiological basis of its responses under water stress are largely unknown. To this end, an ecophysiological assessment of the conventional 110-Richter (110R) and SO4, and the new M1 and M4 rootstocks was carried out in potted ungrafted plants. During one season, these Vitis genotypes were grown under greenhouse conditions and subjected to two water regimes, well-watered and water deficit. Water potentials of plants under water deficit down to < -1.4 MPa, and net photosynthesis (AN) <5 μmol m-2 s-1 did not cause leaf oxidative stress damage compared to well-watered conditions in any of the genotypes. The antioxidant capacity was sufficient to neutralize the mild oxidative stress suffered. Under both treatments, gravimetric differences in daily water use were observed among genotypes, leading to differences in the biomass of root, shoot and leaf. Under well-watered conditions, SO4 and 110R were the most vigorous and M1 and M4 the least. However, under water stress, SO4 exhibited the greatest reduction in biomass while M4 showed the lowest. Remarkably, under these conditions, SO4 reached the least negative stem water potential (Ψstem), while M1 reduced stomatal conductance (gs) and AN the most. In addition, SO4 and M1 genotypes also showed the highest and lowest hydraulic conductance values, respectively. Our results suggest that there are differences in water use regulation among genotypes, not only attributed to differences in stomatal regulation or intrinsic water use efficiency at the leaf level. Therefore, because no differences in canopy-to-root ratio were achieved, it is hypothesized that xylem vessel anatomical differences may be driving the reported differences among rootstocks performance. Results demonstrate that each Vitis rootstock differs in its ecophysiological responses under water stress.

Making sense of available information for climate change adaptation and building resilience into wine production systems across the world

Effects of climate change on viticulture systems and winemaking processes are being felt across the world. The IPCC 6thAssessment Report concluded widespread and rapid changes have occurred, the scale of recent changes being unprecedented over many centuries to many thousands of years. These changes will continue under all emission scenarios considered, including increases in frequency and intensity of hot extremes, heatwaves, heavy precipitation and droughts. Wine companies need tools and models allowing to peer into the future and identify the moment for intervention and measures for mitigation and/or avoidance. Previously, we presented conceptual guidelines for a 5-stage framework for defining adaptation strategies for wine businesses. That framework allows for direct comparison of different solutions to mitigate perceived climate change risks. Recent global climatic evolution and multiple reports of severe events since then (smoke taint, heatwave and droughts, frost, hail and floods, rising sea levels) imply urgency in providing effective tools to tackle the multiple perceived risks. A coordinated drive towards a higher level of resilience is therefore required. Recent publications such as the Australian Wine Future Climate Atlas and results from projects such as H2020 MED-GOLD inform on expected climate change impacts to the wine sector, foreseeing the climate to expect at regional and vineyard scale in coming decades. We present examples of practical application of the Climate Change Adaptation Framework (CCAF) to impacts affecting wine production in two wine regions: Barossa (Australia) and Douro (Portugal). We demonstrate feasibility of the framework for climate adaptation from available data and tools to estimate historical climate-induced profitability loss, to project it in the future and to identify critical moments when disruptions may occur if timely measures are not implemented. Finally, we discuss adaptation measures and respective timeframes for successful mitigation of disruptive risk while enhancing resilience of wine systems.