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J. C. Marques - One of the best experts on this subject based on the ideXlab platform.
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Classification of Boal, Malvazia, Sercial and Verdelho Wines based on terpenoid patterns
Food Chemistry, 2020Co-Authors: Jose S Câmara, M.a. Alves, J. C. MarquesAbstract:Abstract Thirty-six Madeira Wine samples from Boal, Malvazia, Sercial and Verdelho white grape varieties were analyzed in order to estimate the free fraction of monoterpenols and C 13 norisoprenoids (terpenoid compounds) using dynamic headspace solid phase micro-extraction (HS-SPME) technique coupled with gas chromatography–mass spectrometry (GC–MS). The average values from three vintages (1998–2000) show that these Wines have characteristic profiles of terpenoid compounds. Malvazia Wines exhibits the highest values of total free monoterpenols, contrary to Verdelho Wines which had the lowest levels of terpenoids but produced the highest concentration of farnesol. The use of multivariate analysis techniques allows establishing relations between the compounds and the varieties under investigation. Principal component analysis (PCA) and linear discriminant analysis (LDA) were applied to the obtained matrix data. A good separation and classification power between the four groups as a function of their varietal origin was observed.
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Multivariate Statistical Monitoring of Wine Ageing Processes
Computer-aided chemical engineering, 2020Co-Authors: Ana C Pereira, Marco S Reis, Pedro M Saraiva, J. C. MarquesAbstract:Abstract The flavor pattern is a key quality feature in the Wine industry. Being the result of a complex interplay of different classes of volatile compounds, it presents an important evolution during the final and longer phase of the Wine production process: the ageing period. In this paper, we present a data analysis framework for supporting the proper monitoring of the quality of Wine products, during the ageing process, focusing on their flavor characteristics. We focus our analysis on a high quality Portuguese Wine, the fortified Madeira Wine, for which samples were collected over an extended time period, and analyzed in terms of their flavor composition using GC-MS. Then, several classification methodologies for age prediction were developed and evaluated, after a preliminary feature extraction stage using partial least squares for discriminant analysis (PLS-DA). Our analysis shows that it is indeed possible to identify the relevant ageing patterns and trends in a lower dimensional subspace, and to achieve very interesting classification performances, despite the natural variability present in Wine products. The proposed framework also offers the potential to be applied in identity assurance and fraud detection tasks.
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is sotolon relevant to the aroma of Madeira Wine blends
Biomolecules, 2019Co-Authors: Joao M Gaspar, Vanda Pereira, A I Freitas, Qianzhu Zhao, Joao M Leca, J. C. MarquesAbstract:Madeira Wine (MW) oxidative aging results in the formation of several key aromas. Little is still known about their odor relevance to the aroma of the most commercialized MWs. This report presents an in-depth study of the odor impact of sotolon in MW blends. First, its odor perception was estimated in MWs according to ASTM E679, testing different 3-year-old (3-yo) commercial blends. The odor relevance of sotolon in the aroma of 3-, 5-, and 10-yo commercial blends (89 MWs) was then appraised by calculating its Odor Activity Value (OAV), after determining its content by RP-HPLC-MS/MS. The sotolon odor perception in MW was as low as 23 µg/L, although it was found that little differences in the Wine matrix influenced its perception. OAVs varied between 0.1 and 22, increasing with the blend age. Considering that 16% of the OAVs are higher than 10 (mostly ≥ 10-yo), sotolon was found to be a key contributor to the overall aroma MW blends.
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A Simple Emulsification-Assisted Extraction Method for the GC–MS/SIM Analysis of Wine Markers of Aging and Oxidation: Application for Studying Micro-Oxygenation in Madeira Wine
Food Analytical Methods, 2018Co-Authors: Ana I. Freitas, Vanda Pereira, Francisco Albuquerque, Joao M Leca, Ana C Pereira, J. C. MarquesAbstract:Sotolon and the heterocyclic acetals of glycerol are known as potential aging and oxidation markers in fortified Wines such as Madeira, Port, and Sherry. Thus, determining the evolution of these compounds under different oxidative aging conditions is important for fortified Wine quality purposes. This study proposes a new methodology based on a miniaturized emulsification extraction followed by GC–MS/SIM, which was developed and optimized to follow the formation of sotolon and heterocyclic acetals in fortified Wines that were submitted to traditional accelerated aging and micro-oxygenation. The optimization was achieved by means of a mixed-level factorial design, considering 3 factors: sample volume, extractant volume, and concentrated extract volume, by performing 19 experiments in duplicate. The extraction was optimized using 8 mL of Wine sample, 5 mL of dichloromethane, concentrating the extract up to 10-fold. The method performance was evaluated for sotolon, using a matrix-matched calibration between 10 and 2000 μg/L. The selectivity was confirmed through the analysis of real samples. The methodology showed good linearity (R^2 = 0.999), high sensitivity (LOQ = 6.8 μg/L), recovery about 105%, and good precision (less than 8 and 9%, evaluated by the variation of intra- and inter-day measurements, respectively). This is the first methodology that revealed to be an excellent tool to simultaneously follow the formation of sotolon and heterocyclic acetals in Madeira Wines, using an inexpensive, simple, efficient, and effective experimental layout. Indeed, it was shown that traditional accelerated aging and micro-oxygenation have impact on the formation of such molecules.
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Acetic acid and ethyl acetate in Madeira Wines: Evolution with ageing and assessment of the odour rejection threshold
Ciencia E Tecnica Vitivinicola, 2017Co-Authors: Andreia Miranda, Francisco Albuquerque, Vanda Pereira, Marisela Pontes, J. C. MarquesAbstract:Madeira Wine is an internationally recognized fortified Wine, characterized by a complex flavour and high longevity. Little is known about the impact of volatile acidity in its features along ageing. Thus, this work studied the evolution of acetic acid and ethyl acetate (volatile acidity main contributors) during the ageing processes used in Madeira Wine production, canteiro and estufagem . Wines aged in canteiro for 6 up to 45 years were also evaluated. The odour rejection thresholds (ORT) were assessed in sweet (Malvasia) and dry (Sercial) Wines with 5 and 10 years old, by a regular consumer panel and a non-regular consumer panel. The results showed that the formation trend of acetic acid and ethyl acetate is similar in both ageing processes and is favoured by the ageing, mostly in sweet Wines. The ORT of ethyl acetate was in average 328 mg/L for both panels, while for acetic acid ranged between 1.96 and 5.72 g/L, depending on the evaluation panel and also on the age and sweetness degree of the Madeira Wine. The ORT values expressed in volatile acidity ranged between 1.4 and 3.5 g/L, which are higher than the legal limits. The study pointed out that the olfactory perception of acetic acid and ethyl acetate in Madeira Wines depends on their age and sweetness degree.
Jose S Câmara - One of the best experts on this subject based on the ideXlab platform.
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Classification of Boal, Malvazia, Sercial and Verdelho Wines based on terpenoid patterns
Food Chemistry, 2020Co-Authors: Jose S Câmara, M.a. Alves, J. C. MarquesAbstract:Abstract Thirty-six Madeira Wine samples from Boal, Malvazia, Sercial and Verdelho white grape varieties were analyzed in order to estimate the free fraction of monoterpenols and C 13 norisoprenoids (terpenoid compounds) using dynamic headspace solid phase micro-extraction (HS-SPME) technique coupled with gas chromatography–mass spectrometry (GC–MS). The average values from three vintages (1998–2000) show that these Wines have characteristic profiles of terpenoid compounds. Malvazia Wines exhibits the highest values of total free monoterpenols, contrary to Verdelho Wines which had the lowest levels of terpenoids but produced the highest concentration of farnesol. The use of multivariate analysis techniques allows establishing relations between the compounds and the varieties under investigation. Principal component analysis (PCA) and linear discriminant analysis (LDA) were applied to the obtained matrix data. A good separation and classification power between the four groups as a function of their varietal origin was observed.
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an approach of the Madeira Wine chemistry
Beverages, 2020Co-Authors: Rosa Perestrelo, Catarina Oliveira Silva, Carolina Goncalves, Mariangie Castillo, Jose S CâmaraAbstract:Madeira Wine is a fortified Portuguese Wine, which has a crucial impact on the Madeira Island economy. The particular properties of Madeira Wine result from the unique and specific Winemaking and ageing processes that promote the occurrence of chemical reactions among acids, sugars, alcohols, and polyphenols, which are important to the extraordinary quality of the Wine. These chemical reactions contribute to the appearance of novel compounds and/or the transformation of others, consequently promoting changes in qualitative and quantitative volatile and non-volatile composition. The current review comprises an overview of Madeira Wines related to volatile (e.g., terpenes, norisoprenoids, alcohols, esters, fatty acids) and non-volatile composition (e.g., polyphenols, organic acids, amino acids, biogenic amines, and metals). Moreover, types of aroma compounds, the contribution of volatile organic compounds (VOCs) to the overall Madeira Wine aroma, the change of their content during the ageing process, as well as the establishment of the potential ageing markers will also be reviewed. The viability of several analytical methods (e.g., gas chromatography-mass spectrometry (GC-MS), two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC-ToFMS)) combined with chemometrics tools (e.g., partial least squares regression (PLS-R), partial least squares discriminant analysis (PLS-DA) was investigated to establish potential ageing markers to guarantee the Madeira Wine authenticity. Acetals, furanic compounds, and lactones are the chemical families most commonly related with the ageing process.
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Madeira Wine volatile profile a platform to establish Madeira Wine aroma descriptors
Molecules, 2019Co-Authors: Rosa Perestrelo, Catarina L Silva, Jose S CâmaraAbstract:In the present study we aimed to investigate the volatile organic compounds (VOCs) that may potentially be responsible for specific descriptors of Madeira Wine providing details about Madeira Wine aroma notes at molecular level. Moreover, the Wine aroma profile, based on the obtained data, will be a starting point to evaluate the impact of grape variety (Malvasia, Bual, Sercial, Verdelho and Tinta Negra), type (sweet, medium sweet, dry and medium dry), and age (from 3 to 20 years old) on Madeira Wine sensorial properties. Firstly, a comprehensive and in-depth Madeira Wine volatile profiling was carried out using headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS–SPME/GC–qMS). Secondly, a relation among the varietal, fermentative and aging aroma compounds, and their aroma descriptors with the Madeira Wine sensorial properties was assessed. A total of 82 VOCs, belonging to different chemical families were identified, namely 21 esters, 13 higher alcohols, ten terpenic compounds, nine fatty acids, seven furanic compounds, seven norisoprenoids, six lactones, four acetals, four volatile phenols and one sulphur compound. From a sensorial point of view, during the aging process the Wine lost its freshness and fruitiness odor related to the presence of some varietal and fermentative compounds, whereas other descriptors such as caramel, dried fruits, spicy, toasty and woody, arose during ageing. The Maillard reaction and diffusion from the oak were the most important pathways related with these descriptors. A relationship-based approach was used to explore the impact of grape variety, Wine type, and age on Madeira Wine sensorial properties based on shared number of VOCs and their odors.
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Unraveling Vitis vinifera L. grape maturity markers based on integration of terpenic pattern and chemometric methods
Microchemical Journal, 2018Co-Authors: Rosa Perestrelo, Catarina L Silva, Pedro Silva, Jose S CâmaraAbstract:Abstract The current research attempts to provide an alternative tool for grape maturity measurement related to the Wine composition since, the classical parameters (weight grape berries, sugar content, titratable acidity), commonly used in the Winemaking industry, do not provide any sensorial information. In this context, the evolution of terpenic compounds (TC) during ripening of four V. vinifera L. grape varieties - Bual, Malvasia, Sercial (white grapes) and Tinta Negra (red grapes), was investigated, in addition to the establishment of terpenic pattern, using headspace solid phase microextraction (HS-SPME) combined with GC–MS. Using the optimal analytical conditions were identified 62 TC in the investigated V. vinifera L. grapes. The integration of chromatographic and chemometric data provides a powerful strategy to identify potential maturity markers. The maximum potential of mono- and sesquiterpenic compounds was reached at maturity, whereas the highest levels of norisoprenoids were observed at veraison. Partial Least Squares Regression (PLS-R) was employed to describe the relationship between classical parameters and TC. Based on PLS-R models, three monoterpenic (linalool, α-terpineol, carvomenthol), one sesquiterpenic (bicyclogermacrene) and two norisoprenoids compounds (vitispirane I, β-damascenone) could be used to define the optimum harvest date. The obtained results represent a very important tool to support, in an objective way, the Winemakers decision for long-term strategic planning based on the sensory potentialities of grape varieties and consequently improving the excellence of Madeira Wine.
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Rapid spectrophotometric methods as a tool to assess the total phenolics and antioxidant potential over grape ripening: a case study of Madeira grapes
Journal of Food Measurement and Characterization, 2018Co-Authors: Rosa Perestrelo, Catarina L Silva, Pedro Silva, Jose S CâmaraAbstract:The aim of this study was to improve the knowledge of phenolic content and antioxidant potential during ripening of different grape varieties (Malvasia, Sercial and Tinta Negra) used to produce Madeira Wine. Rapid spectrophotometric methods were selected to obtain this information, since these methods could be used as a routine analytical procedure, being easy, simple, rapid, and cost-effective. A significant correlation was observed between total phenolic content and antioxidant capacity for all grape varieties under study, which suggests that phenolics either alone or in combination are responsible for the grapes antioxidant capacity. Our findings showed significant differences (p < 0.05) for phenolic content and antioxidant capacity for all the studied grape varieties. Sercial grapes showed the highest values of phenolics and antioxidant capacity. Moreover, grape ripening stages revealed a significant impact on grapes phenolic content and antioxidant capacity. This information could be used by viticulturists and Winemakers to improve and define Vitis vinifera L. grapes harvest management in order to maximize its bioactive potential.
Ana C Pereira - One of the best experts on this subject based on the ideXlab platform.
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Multivariate Statistical Monitoring of Wine Ageing Processes
Computer-aided chemical engineering, 2020Co-Authors: Ana C Pereira, Marco S Reis, Pedro M Saraiva, J. C. MarquesAbstract:Abstract The flavor pattern is a key quality feature in the Wine industry. Being the result of a complex interplay of different classes of volatile compounds, it presents an important evolution during the final and longer phase of the Wine production process: the ageing period. In this paper, we present a data analysis framework for supporting the proper monitoring of the quality of Wine products, during the ageing process, focusing on their flavor characteristics. We focus our analysis on a high quality Portuguese Wine, the fortified Madeira Wine, for which samples were collected over an extended time period, and analyzed in terms of their flavor composition using GC-MS. Then, several classification methodologies for age prediction were developed and evaluated, after a preliminary feature extraction stage using partial least squares for discriminant analysis (PLS-DA). Our analysis shows that it is indeed possible to identify the relevant ageing patterns and trends in a lower dimensional subspace, and to achieve very interesting classification performances, despite the natural variability present in Wine products. The proposed framework also offers the potential to be applied in identity assurance and fraud detection tasks.
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A Simple Emulsification-Assisted Extraction Method for the GC–MS/SIM Analysis of Wine Markers of Aging and Oxidation: Application for Studying Micro-Oxygenation in Madeira Wine
Food Analytical Methods, 2018Co-Authors: Ana I. Freitas, Vanda Pereira, Francisco Albuquerque, Joao M Leca, Ana C Pereira, J. C. MarquesAbstract:Sotolon and the heterocyclic acetals of glycerol are known as potential aging and oxidation markers in fortified Wines such as Madeira, Port, and Sherry. Thus, determining the evolution of these compounds under different oxidative aging conditions is important for fortified Wine quality purposes. This study proposes a new methodology based on a miniaturized emulsification extraction followed by GC–MS/SIM, which was developed and optimized to follow the formation of sotolon and heterocyclic acetals in fortified Wines that were submitted to traditional accelerated aging and micro-oxygenation. The optimization was achieved by means of a mixed-level factorial design, considering 3 factors: sample volume, extractant volume, and concentrated extract volume, by performing 19 experiments in duplicate. The extraction was optimized using 8 mL of Wine sample, 5 mL of dichloromethane, concentrating the extract up to 10-fold. The method performance was evaluated for sotolon, using a matrix-matched calibration between 10 and 2000 μg/L. The selectivity was confirmed through the analysis of real samples. The methodology showed good linearity (R^2 = 0.999), high sensitivity (LOQ = 6.8 μg/L), recovery about 105%, and good precision (less than 8 and 9%, evaluated by the variation of intra- and inter-day measurements, respectively). This is the first methodology that revealed to be an excellent tool to simultaneously follow the formation of sotolon and heterocyclic acetals in Madeira Wines, using an inexpensive, simple, efficient, and effective experimental layout. Indeed, it was shown that traditional accelerated aging and micro-oxygenation have impact on the formation of such molecules.
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Advanced predictive methods for Wine age prediction: Part II – A comparison study of multiblock regression approaches
Talanta, 2017Co-Authors: Maria P. Campos, Ana C Pereira, Ricardo Sousa, Marco S ReisAbstract:Abstract In this article, we extend the scope of the first paper of the sequel, which was dedicated to the analysis of advanced single-block regression methods (Rendall et al., 2016) [1], to the class of multiblock regression approaches. The datasets contemplated for developing the multiblock approaches are the same as in the former publication: volatile, polyphenols, organic acids composition and the UV–Vis spectra. The context is still the prediction of the ageing time of one of finest Portuguese fortified Wines, the Madeira Wine, but now the data collected from the different analytical sources is explored simultaneously, in a more structured and informative way, through multiblock methodologies. The goal of this paper is to provide a critical assessment of a rich variety of multiblock regression methods, namely: Concatenated PLS, Multiblock PLS (MBPLS), Hierarchical PLS (HPLS), Network-Induced Supervised Learning (NI-SL) and Sequential Orthogonalised Partial Least Squares (SO-PLS). A comparison of block scaling methods was also undertaken for the Concatenated PLS algorithm, and new block scaling methods were proposed that led to better prediction performances. This study explores and reveals the potential advantages of applying multiblock methods for fusing datasets from different sources, from both the predictive and interpretability perspectives.
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Advanced predictive methods for Wine age prediction: Part I – A comparison study of single-block regression approaches based on variable selection, penalized regression, latent variables and tree-based ensemble methods
Talanta, 2016Co-Authors: Ricardo Rendall, Ana C Pereira, Marco S ReisAbstract:Abstract In this paper we test and compare advanced predictive approaches for estimating Wine age in the context of the production of a high quality fortified Wine – Madeira Wine. We consider four different data sets, namely, volatile, polyphenols, organic acids and the UV–vis spectra. Each one of these data sets contain chemical information of a different nature and present diverse data structures, namely a different dimensionality, level of collinearity and degree of sparsity. These different aspects may imply the use of different modelling approaches in order to better explore the data set's information content, namely their predictive potential for Wine age. This happens to be so, because different regression methods have different prior assumptions regarding the predictors, response variable(s) and the data generating mechanism, which may or may not find good adherence to the case study under analysis. In order to cover a wide range of modelling domains, we have incorporated in this work methods belonging to four very distinct classes of approaches that cover most applications found in practice: linear regression with variable selection, penalized regression, latent variables regression and tree-based ensemble methods. We have also developed a rigorous comparison framework based on a double Monte Carlo cross-validation scheme, in order to perform the relative assessment of the performance of the various methods. Upon comparison, models built using the polyphenols and volatile composition data sets led to better Wine age predictions, showing lower errors under testing conditions. Furthermore, the results obtained for the polyphenols data set suggest a more sparse structure that can be further explored in order to reduce the number of measured variables. In terms of regression methods, tree-based methods, and boosted regression trees in particular, presented the best results for the polyphenols, volatile and the organic acid data sets, suggesting a possible presence of a nonlinear relationship between predictors and response. Regarding the UV–vis data set, penalized regression methods (ridge regression, LASSO and elastic nets) presented the best results, albeit methods such as partial least squares (PLS) or principal component regression (PCR) are often the practitioners’ preferred choice.
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Modelling the ageing process: A novel strategy to analyze the Wine evolution towards the expected features
Chemometrics and Intelligent Laboratory Systems, 2016Co-Authors: Ana C Pereira, J. C. Marques, Vanda Pereira, Maria J Carvalho, Francisco Albuquerque, Joao M Leca, Andreia Miranda, Marco S ReisAbstract:Abstract In this work we present a new strategy to monitor the Wine evolution during the ageing process. More specifically, we validate a procedure for analyzing how Wine evolves during the ageing process in relation to the desired and expected quality features and we apply the proposed methodology to the case of a Portuguese fortified Wine, the Madeira Wine, where we compare the Wine evolution under two different ageing processes. The approach developed consists on modeling samples labeled as aged reference Wines (5 year old Madeira Wines), produced from four different grape varieties, and then analyze how and in which extent young Wines (up to 3 years old) come closer to the reference data set. The analysis is based on a comprehensive set of chemical data, including: polyphenolic composition, organic acids, reducing sugars, color and oenological parameters, commonly used as routine quality control information. The study considers several feature extraction methods, such as: Principal Components of Analysis (PCA), Independent Component of Analysis (ICA) and Partial Least Squares (PLS). The classification methodologies tested were: Linear Discriminant Analysis (LDA), nearest neighbor ( k -NN) and Soft Independent Modelling by Class Analogy (SIMCA). The different options of preprocessing/feature extraction/classification were evaluated and compared using a Monte Carlo approach. From our analysis, the best combination of feature extraction/classification methodologies was PLS/LDA, which presented a classification performance of approximately 90% for three out of the four classes modeled, and of about 78% for the remaining one. Regarding the Wines monitored during the first 3 years, our analysis revealed that they indeed mature in relation to the five year old reference Wines. Furthermore, for some Wines, it is possible to detect differences between the two ageing processes analyzed. This study is of particular importance for this type of Wines, where the ageing process plays a central role for attaining the expected quality levels, implying significant risks and costs for local and industrial producers. Notwithstanding the specific case study presented, the strategy outlined can be extrapolated to other products with similar characteristics in terms of their monitoring and process control.
Rosa Perestrelo - One of the best experts on this subject based on the ideXlab platform.
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an approach of the Madeira Wine chemistry
Beverages, 2020Co-Authors: Rosa Perestrelo, Catarina Oliveira Silva, Carolina Goncalves, Mariangie Castillo, Jose S CâmaraAbstract:Madeira Wine is a fortified Portuguese Wine, which has a crucial impact on the Madeira Island economy. The particular properties of Madeira Wine result from the unique and specific Winemaking and ageing processes that promote the occurrence of chemical reactions among acids, sugars, alcohols, and polyphenols, which are important to the extraordinary quality of the Wine. These chemical reactions contribute to the appearance of novel compounds and/or the transformation of others, consequently promoting changes in qualitative and quantitative volatile and non-volatile composition. The current review comprises an overview of Madeira Wines related to volatile (e.g., terpenes, norisoprenoids, alcohols, esters, fatty acids) and non-volatile composition (e.g., polyphenols, organic acids, amino acids, biogenic amines, and metals). Moreover, types of aroma compounds, the contribution of volatile organic compounds (VOCs) to the overall Madeira Wine aroma, the change of their content during the ageing process, as well as the establishment of the potential ageing markers will also be reviewed. The viability of several analytical methods (e.g., gas chromatography-mass spectrometry (GC-MS), two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC-ToFMS)) combined with chemometrics tools (e.g., partial least squares regression (PLS-R), partial least squares discriminant analysis (PLS-DA) was investigated to establish potential ageing markers to guarantee the Madeira Wine authenticity. Acetals, furanic compounds, and lactones are the chemical families most commonly related with the ageing process.
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Madeira Wine volatile profile a platform to establish Madeira Wine aroma descriptors
Molecules, 2019Co-Authors: Rosa Perestrelo, Catarina L Silva, Jose S CâmaraAbstract:In the present study we aimed to investigate the volatile organic compounds (VOCs) that may potentially be responsible for specific descriptors of Madeira Wine providing details about Madeira Wine aroma notes at molecular level. Moreover, the Wine aroma profile, based on the obtained data, will be a starting point to evaluate the impact of grape variety (Malvasia, Bual, Sercial, Verdelho and Tinta Negra), type (sweet, medium sweet, dry and medium dry), and age (from 3 to 20 years old) on Madeira Wine sensorial properties. Firstly, a comprehensive and in-depth Madeira Wine volatile profiling was carried out using headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS–SPME/GC–qMS). Secondly, a relation among the varietal, fermentative and aging aroma compounds, and their aroma descriptors with the Madeira Wine sensorial properties was assessed. A total of 82 VOCs, belonging to different chemical families were identified, namely 21 esters, 13 higher alcohols, ten terpenic compounds, nine fatty acids, seven furanic compounds, seven norisoprenoids, six lactones, four acetals, four volatile phenols and one sulphur compound. From a sensorial point of view, during the aging process the Wine lost its freshness and fruitiness odor related to the presence of some varietal and fermentative compounds, whereas other descriptors such as caramel, dried fruits, spicy, toasty and woody, arose during ageing. The Maillard reaction and diffusion from the oak were the most important pathways related with these descriptors. A relationship-based approach was used to explore the impact of grape variety, Wine type, and age on Madeira Wine sensorial properties based on shared number of VOCs and their odors.
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Unraveling Vitis vinifera L. grape maturity markers based on integration of terpenic pattern and chemometric methods
Microchemical Journal, 2018Co-Authors: Rosa Perestrelo, Catarina L Silva, Pedro Silva, Jose S CâmaraAbstract:Abstract The current research attempts to provide an alternative tool for grape maturity measurement related to the Wine composition since, the classical parameters (weight grape berries, sugar content, titratable acidity), commonly used in the Winemaking industry, do not provide any sensorial information. In this context, the evolution of terpenic compounds (TC) during ripening of four V. vinifera L. grape varieties - Bual, Malvasia, Sercial (white grapes) and Tinta Negra (red grapes), was investigated, in addition to the establishment of terpenic pattern, using headspace solid phase microextraction (HS-SPME) combined with GC–MS. Using the optimal analytical conditions were identified 62 TC in the investigated V. vinifera L. grapes. The integration of chromatographic and chemometric data provides a powerful strategy to identify potential maturity markers. The maximum potential of mono- and sesquiterpenic compounds was reached at maturity, whereas the highest levels of norisoprenoids were observed at veraison. Partial Least Squares Regression (PLS-R) was employed to describe the relationship between classical parameters and TC. Based on PLS-R models, three monoterpenic (linalool, α-terpineol, carvomenthol), one sesquiterpenic (bicyclogermacrene) and two norisoprenoids compounds (vitispirane I, β-damascenone) could be used to define the optimum harvest date. The obtained results represent a very important tool to support, in an objective way, the Winemakers decision for long-term strategic planning based on the sensory potentialities of grape varieties and consequently improving the excellence of Madeira Wine.
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Rapid spectrophotometric methods as a tool to assess the total phenolics and antioxidant potential over grape ripening: a case study of Madeira grapes
Journal of Food Measurement and Characterization, 2018Co-Authors: Rosa Perestrelo, Catarina Silva, Pedro Silva, José Sousa CâmaraAbstract:The aim of this study was to improve the knowledge of phenolic content and antioxidant potential during ripening of different grape varieties (Malvasia, Sercial and Tinta Negra) used to produce Madeira Wine. Rapid spectrophotometric methods were selected to obtain this information, since these methods could be used as a routine analytical procedure, being easy, simple, rapid, and cost-effective. A significant correlation was observed between total phenolic content and antioxidant capacity for all grape varieties under study, which suggests that phenolics either alone or in combination are responsible for the grapes antioxidant capacity. Our findings showed significant differences ( p
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Rapid spectrophotometric methods as a tool to assess the total phenolics and antioxidant potential over grape ripening: a case study of Madeira grapes
Journal of Food Measurement and Characterization, 2018Co-Authors: Rosa Perestrelo, Catarina L Silva, Pedro Silva, Jose S CâmaraAbstract:The aim of this study was to improve the knowledge of phenolic content and antioxidant potential during ripening of different grape varieties (Malvasia, Sercial and Tinta Negra) used to produce Madeira Wine. Rapid spectrophotometric methods were selected to obtain this information, since these methods could be used as a routine analytical procedure, being easy, simple, rapid, and cost-effective. A significant correlation was observed between total phenolic content and antioxidant capacity for all grape varieties under study, which suggests that phenolics either alone or in combination are responsible for the grapes antioxidant capacity. Our findings showed significant differences (p < 0.05) for phenolic content and antioxidant capacity for all the studied grape varieties. Sercial grapes showed the highest values of phenolics and antioxidant capacity. Moreover, grape ripening stages revealed a significant impact on grapes phenolic content and antioxidant capacity. This information could be used by viticulturists and Winemakers to improve and define Vitis vinifera L. grapes harvest management in order to maximize its bioactive potential.
Vanda Pereira - One of the best experts on this subject based on the ideXlab platform.
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is sotolon relevant to the aroma of Madeira Wine blends
Biomolecules, 2019Co-Authors: Joao M Gaspar, Vanda Pereira, A I Freitas, Qianzhu Zhao, Joao M Leca, J. C. MarquesAbstract:Madeira Wine (MW) oxidative aging results in the formation of several key aromas. Little is still known about their odor relevance to the aroma of the most commercialized MWs. This report presents an in-depth study of the odor impact of sotolon in MW blends. First, its odor perception was estimated in MWs according to ASTM E679, testing different 3-year-old (3-yo) commercial blends. The odor relevance of sotolon in the aroma of 3-, 5-, and 10-yo commercial blends (89 MWs) was then appraised by calculating its Odor Activity Value (OAV), after determining its content by RP-HPLC-MS/MS. The sotolon odor perception in MW was as low as 23 µg/L, although it was found that little differences in the Wine matrix influenced its perception. OAVs varied between 0.1 and 22, increasing with the blend age. Considering that 16% of the OAVs are higher than 10 (mostly ≥ 10-yo), sotolon was found to be a key contributor to the overall aroma MW blends.
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A Simple Emulsification-Assisted Extraction Method for the GC–MS/SIM Analysis of Wine Markers of Aging and Oxidation: Application for Studying Micro-Oxygenation in Madeira Wine
Food Analytical Methods, 2018Co-Authors: Ana I. Freitas, Vanda Pereira, Francisco Albuquerque, Joao M Leca, Ana C Pereira, J. C. MarquesAbstract:Sotolon and the heterocyclic acetals of glycerol are known as potential aging and oxidation markers in fortified Wines such as Madeira, Port, and Sherry. Thus, determining the evolution of these compounds under different oxidative aging conditions is important for fortified Wine quality purposes. This study proposes a new methodology based on a miniaturized emulsification extraction followed by GC–MS/SIM, which was developed and optimized to follow the formation of sotolon and heterocyclic acetals in fortified Wines that were submitted to traditional accelerated aging and micro-oxygenation. The optimization was achieved by means of a mixed-level factorial design, considering 3 factors: sample volume, extractant volume, and concentrated extract volume, by performing 19 experiments in duplicate. The extraction was optimized using 8 mL of Wine sample, 5 mL of dichloromethane, concentrating the extract up to 10-fold. The method performance was evaluated for sotolon, using a matrix-matched calibration between 10 and 2000 μg/L. The selectivity was confirmed through the analysis of real samples. The methodology showed good linearity (R^2 = 0.999), high sensitivity (LOQ = 6.8 μg/L), recovery about 105%, and good precision (less than 8 and 9%, evaluated by the variation of intra- and inter-day measurements, respectively). This is the first methodology that revealed to be an excellent tool to simultaneously follow the formation of sotolon and heterocyclic acetals in Madeira Wines, using an inexpensive, simple, efficient, and effective experimental layout. Indeed, it was shown that traditional accelerated aging and micro-oxygenation have impact on the formation of such molecules.
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odor detection threshold odt and odor rejection threshold ort determination of sotolon in Madeira Wine a preliminary study
agriculture 2018 Vol. 3 Pages 172-180, 2018Co-Authors: Joao M Gaspar, Vanda Pereira, And Jose C MarquesAbstract:Madeira is a fortified Wine, well renowned worldwide. It is during the aging process that its characteristic bouquet is developed, through the formation of specific aromas. Sotolon (3-hydroxy-4,5-dimethyl-2(5 H )-furanone) is frequently pointed out as one of the molecules responsible for the aroma of the finest Madeiras. The present work serves as a preliminary insight on the sensorial impact of this compound in Madeira Wine. The odor detection threshold of sotolon in a sweet-type Madeira was obtained by the 3-Alternative Forced Choice method. The estimated threshold value was obtained by 19 non-trained and non-expert panelists, within the spiked range 4–314 µg/L. An odor threshold of 112 µg/L was obtained using a 3-year-old Madeira with 6.3 ± 0.4 µg/L endogenous sotolon. This result is about 6-fold higher than those previously reported for other fortified Wines. A Paired Preference test was chosen to determine the concentration at which the panelists would reject the Wine spiked with sotolon. Nineteen panelists assessed a series of spiked concentrations ranging from 253–3464 µg/L. Within this range, it is not possible to define the concentration value from which the aroma of sotolon it is no longer pleasant. Thus, an odor rejection threshold could not be obtained. Indeed, the study also suggests that sotolon does not become unpleasant at higher concentrations.
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Acetic acid and ethyl acetate in Madeira Wines: Evolution with ageing and assessment of the odour rejection threshold
Ciencia E Tecnica Vitivinicola, 2017Co-Authors: Andreia Miranda, Francisco Albuquerque, Vanda Pereira, Marisela Pontes, J. C. MarquesAbstract:Madeira Wine is an internationally recognized fortified Wine, characterized by a complex flavour and high longevity. Little is known about the impact of volatile acidity in its features along ageing. Thus, this work studied the evolution of acetic acid and ethyl acetate (volatile acidity main contributors) during the ageing processes used in Madeira Wine production, canteiro and estufagem . Wines aged in canteiro for 6 up to 45 years were also evaluated. The odour rejection thresholds (ORT) were assessed in sweet (Malvasia) and dry (Sercial) Wines with 5 and 10 years old, by a regular consumer panel and a non-regular consumer panel. The results showed that the formation trend of acetic acid and ethyl acetate is similar in both ageing processes and is favoured by the ageing, mostly in sweet Wines. The ORT of ethyl acetate was in average 328 mg/L for both panels, while for acetic acid ranged between 1.96 and 5.72 g/L, depending on the evaluation panel and also on the age and sweetness degree of the Madeira Wine. The ORT values expressed in volatile acidity ranged between 1.4 and 3.5 g/L, which are higher than the legal limits. The study pointed out that the olfactory perception of acetic acid and ethyl acetate in Madeira Wines depends on their age and sweetness degree.
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Modelling the ageing process: A novel strategy to analyze the Wine evolution towards the expected features
Chemometrics and Intelligent Laboratory Systems, 2016Co-Authors: Ana C Pereira, J. C. Marques, Vanda Pereira, Maria J Carvalho, Francisco Albuquerque, Joao M Leca, Andreia Miranda, Marco S ReisAbstract:Abstract In this work we present a new strategy to monitor the Wine evolution during the ageing process. More specifically, we validate a procedure for analyzing how Wine evolves during the ageing process in relation to the desired and expected quality features and we apply the proposed methodology to the case of a Portuguese fortified Wine, the Madeira Wine, where we compare the Wine evolution under two different ageing processes. The approach developed consists on modeling samples labeled as aged reference Wines (5 year old Madeira Wines), produced from four different grape varieties, and then analyze how and in which extent young Wines (up to 3 years old) come closer to the reference data set. The analysis is based on a comprehensive set of chemical data, including: polyphenolic composition, organic acids, reducing sugars, color and oenological parameters, commonly used as routine quality control information. The study considers several feature extraction methods, such as: Principal Components of Analysis (PCA), Independent Component of Analysis (ICA) and Partial Least Squares (PLS). The classification methodologies tested were: Linear Discriminant Analysis (LDA), nearest neighbor ( k -NN) and Soft Independent Modelling by Class Analogy (SIMCA). The different options of preprocessing/feature extraction/classification were evaluated and compared using a Monte Carlo approach. From our analysis, the best combination of feature extraction/classification methodologies was PLS/LDA, which presented a classification performance of approximately 90% for three out of the four classes modeled, and of about 78% for the remaining one. Regarding the Wines monitored during the first 3 years, our analysis revealed that they indeed mature in relation to the five year old reference Wines. Furthermore, for some Wines, it is possible to detect differences between the two ageing processes analyzed. This study is of particular importance for this type of Wines, where the ageing process plays a central role for attaining the expected quality levels, implying significant risks and costs for local and industrial producers. Notwithstanding the specific case study presented, the strategy outlined can be extrapolated to other products with similar characteristics in terms of their monitoring and process control.
