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Riccardo Flamini - One of the best experts on this subject based on the ideXlab platform.
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Applications of Solid-Phase Microextraction and Gas Chromatography/Mass Spectrometry (SPME-GC/MS) in the Study of Grape and Wine Volatile Compounds
MDPI AG, 2014Co-Authors: Annarita Panighel, Riccardo FlaminiAbstract:Volatile compounds are responsible for the Wine “bouquet”, which is perceived by sniffing the headspace of a glass, and of the aroma component (palate-aroma) of the overall flavor, which is perceived on drinking. Grape aroma compounds are transferred to the Wine and undergo minimal alteration during fermentation (e.g., monoterpenes and methoxypyrazines); others are precursors of aroma compounds which form in Winemaking and during Wine Aging (e.g., glycosidically-bound volatile compounds and C13-norisoprenoids). Headspace solid phase microextraction (HS-SPME) is a fast and simple technique which was developed for analysis of volatile compounds. This review describes some SPME methods coupled with gas chromatography/mass spectrometry (GC/MS) used to study the grape and Wine volatiles
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changes in chemical composition of a red Wine aged in acacia cherry chestnut mulberry and oak wood barrels
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Mirko De Rosso, Annarita Panighel, Antonio Dalla Vedova, Laura Stella, Riccardo FlaminiAbstract:Aging in wooden barrels is a process used to stabilize the color and enrich the sensorial characteristics of Wine. Many compounds are released from wood into the Wine; oxygen permeation through the wood favors formation of new anthocyanin and tannin derivatives. Recently, polyphenols and volatile compounds released from acacia, chestnut, cherry, mulberry, and oak wood used in making barrels for spirits and Wine Aging were studied. Here, changes in volatile and polyphenolic compositions of a red Wine aged for 9 months in acacia, cherry, chestnut, mulberry, and oak barrels are studied. Mulberry showed significant decreases of fruity-note ethyl esters and ethylguaiacol and a great cession of ethylphenol (horsey-odor defect). Cherry promoted the highest polyphenol oxidation, making it less suitable for long Aging. LC/ESI-MS(n) showed the relevant presence of cis- and trans-piceatannol in mulberry-aged Wine, a phytoalexin with antileukemia and antimelanoma activities.
Victor De Freitas - One of the best experts on this subject based on the ideXlab platform.
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Wine inspired chemistry anthocyanin transformations for a portfolio of natural colors
Synlett, 2017Co-Authors: Joana Oliveira, Nuno Mateus, Victor De FreitasAbstract:During Wine Aging and maturation, anthocyanins can react with flavanols (directly or mediated by aldehydes) and with small molecules derived from yeast metabolism during fermentation. It has been demonstrated that A-type vitisins (the main pyranoanthocyanins found in red Wines) can react with other Wine components yielding pyranoanthocyanin pigments with different colors ranging from yellow to turquoise blue. Wine-color chemistry has been an inspiration for the synthesis of new molecules with unique chromatic features. 1 Introduction 2 Formation of Anthocyanin Derivatives 3 Conclusion and Outlook
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Antioxidant Features of Red Wine Pyranoanthocyanins: Experimental and Theoretical Approaches
2014Co-Authors: Joana Azevedo, Victor De Freitas, Joana Oliveira, Luis Cruz, Natércia Teixeira, Natércia F. Brás, Nuno MateusAbstract:This work is focused on the study of the antioxidant properties of red Wine anthocyanin derivatives (carboxypyranoanthocyanins, methylpyranoanthocyanins, oxovitisins, and pyranoanthocyanin-phenolics) derived from malvidin-3-glucoside. Some antioxidant features were determined using the DPPH assay and the ability to delay lipid peroxidation in a liposome membrane system by monitoring oxygen consumption. The pyranoanthocyanin-phenolics have higher antioxidant potential than that of malvidin-3-glucoside, suggesting that the addition of a catechol or flavanol moiety increases the antioxidant capacity. The only derivatives that showed lower antioxidant features than malvidin-3-glucoside were oxovitisins and methylpyranomalvidin-3-glucoside. Also, the radical scavenging capacity of these pyranoanthocyanins was computationally explored using DFT methods. All pyranoanthocyanins were suggested as good candidates as antioxidant compounds because they easily donate an H atom to the free radicals, originating stable species. Altogether, these results support the fact that the antioxidant potential arising from anthocyanins is not impaired by some of their transformations during red Wine Aging
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reaction between hydroxycinnamic acids and anthocyanin pyruvic acid adducts yielding new portisins
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Joana Oliveira, Victor De Freitas, And Artur M S Silva, Nuno MateusAbstract:Three new anthocyanin-derived pigments were found to occur in a 2-year-old Port red Wine. Their structures were elucidated through LC/DAD-MS and NMR analysis and were found to correspond to a pyranoanthocyanin moiety linked to substituted cinnamyl substituents. The structures of these compounds are very similar to the one already reported for portisins, with a phenolic moiety replacing the catechin moiety. The newly formed anthocyanin-derived compounds display a bathochromic shift of the lambdamax ( approximately 540 nm) when compared with their anthocyanin-pyruvic acid adduct precursor (lambdamax = 511 nm), which may be due to the extended conjugation of the pi electrons in the structures of those pigments. Studies performed in model solutions helped to clarify the formation mechanism of these pigments that can result from the nucleophilic attack of the olefinic double bond of a hydroxycinnamic acid to the eletrophilic C-10 position of the anthocyanin-pyruvic acid adduct, followed by the loss of a formic acid molecule and decarboxylation. The chromatic characterization of these malvidin-3-glucoside-derived compounds revealed a higher resistance to discoloration against the nucleophilic attack by water and bisulfite when compared to malvidin-3-glucoside that is almost converted into its colorless hemiacetal form. However, the resistance to discoloration of these new pigments is not as high as the one reported for catechin-derived portisins. This could be explained by the presence of a smaller group (hydroxycinnamyl group), which does not protect so efficiently the chromophore against nucleophilic attack at the C-2 position. The occurrence of these pigments in red Wine highlights new chemical pathways involving anthocyanin-pyruvic acid derivatives as precursors for the formation of new pigments in subsequent stages of Wine Aging that may contribute to its color evolution.
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a new class of blue anthocyanin derived pigments isolated from red Wines
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Nuno Mateus, Celestino Santosbuelga, Julian C Rivasgonzalo, Victor De FreitasAbstract:Two newly formed anthocyanin-derived pigments that revealed unique spectroscopic features, showing maximum absorption in their UV−vis spectra at 575 nm, were isolated by TSK Toyopearl HW-40 (S) gel column chromatography and semipreparative HPLC from an aged Port red Wine. Further characterization by ESI/MS and NMR (1H, gCOSY) showed them to belong to a new class of pigments described here for the first time, the structure of which consisted of a pyranoanthocyanin moiety linked to a flavanol by a vinyl bridge. The extended conjugation of the π electrons throughout all the pigment molecule is likely to confer a higher stability on it and is probably the origin of the intense blue color. The formation of these pigments was found to arise from the reaction between anthocyanin−pyruvic acid adducts and vinyl−flavanol adducts. Keywords: Pyranoanthocyanin; flavanols; red Wine; Aging; blue color
Pierre-louis Teissedre - One of the best experts on this subject based on the ideXlab platform.
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Oak wood offers a wide range of tools for Wine Aging, which one to choose?
'Universite de Bordeaux', 2021Co-Authors: María Reyes González-centeno, Pierre-louis Teissedre, Kleopatra ChiraAbstract:The phenolic, aromatic and sensory evolution of a red Wine under different oak Aging conditions was evaluated. Neither phenolic nor fruity aromatic contents and profiles were impacted by the Aging container or the derived oak products used. Meanwhile, a different woody aroma content was observed depending on the exposed wood area to Wine volume ratio. From a sensory point of view, higher smoky, vanilla and/or spicy flavours were identified for all oak-aged Wines when compared to the control (stainless steel tank), but they were all perceived as being as fruity as the control
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influence of wood barrels classified by nirs on the ellagitannin content composition and on the organoleptic properties of Wine
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Julien Michel, Alexandra Le Floch, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Pierre-louis TeissedreAbstract:Ellagitannins are extracted from oak wood during Wine Aging in oak barrels. This research is based on the NIRS (Oakscan) oak wood classification according to their index polyphenolic (IP) (between 21.07 and 70.15). Their level in wood is very variable (between 5.95 and 32.91 mg/g dry wood) and influenced their concentration in red Wine (between 2.30 and 32.56 mg/L after 24 months of Aging) and thus their impact on Wine organoleptic properties. The results show a good correlation between the NIRS classification and the chemical analysis (HPLC-UV-MS and acidic hydrolysis procedure) and with the wood ellagitannin level, the ellagitannin extraction kinetic, and the ellagitannins evolution in red Wine (Cabernet Sauvignon). Moreover, a correlation between the NIRS classification and the increasing intensity of some wood aromas (woody, spicy, vanilla, and smoked/toasted), flavors (bitterness and astringency), and a decreasing intensity of fruitiness was also observed.
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impact of concentration of ellagitannins in oak wood on their levels and organoleptic influence in red Wine
Journal of Agricultural and Food Chemistry, 2011Co-Authors: Julien Michel, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Maria Aparecida Azevedo Pereira Da Silva, Pierre-louis TeissedreAbstract:Some wood substances such as ellagitannins can be extracted during Wine Aging in oak barrels. The level of these hydrolyzable tannins in Wine depends of some parameters of oak wood. Their impact on the organoleptic perception of red Wine is poorly known. In our research, oak staves were classified in three different groups according to their level of ellagitannins estimated by NIRS (near infrared spectroscopy) online procedure (Oakscan). First, the ellagitannin level and composition were determine for each classified stave and an excellent correlation between the NIRS classification (low, medium and high potential level of ellagitannin) and the ellagitannin content estimated by HPLC–UV was found. Each different group of NIRS classified staves was then added to red Wine during its Aging in a stainless tank, and the extraction and evolution of the ellagitannins were monitored. A good correlation between the NIRS classification and the concentration of ellagitannins in red Wine Aging in contact with the clas...
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impact of concentration of ellagitannins in oak wood on their levels and organoleptic influence in red Wine
Journal of Agricultural and Food Chemistry, 2011Co-Authors: Julien Michel, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Maria Aparecida Azevedo Pereira Da Silva, Pierre-louis TeissedreAbstract:Some wood substances such as ellagitannins can be extracted during Wine Aging in oak barrels. The level of these hydrolyzable tannins in Wine depends of some parameters of oak wood. Their impact on the organoleptic perception of red Wine is poorly known. In our research, oak staves were classified in three different groups according to their level of ellagitannins estimated by NIRS (near infrared spectroscopy) online procedure (Oakscan). First, the ellagitannin level and composition were determine for each classified stave and an excellent correlation between the NIRS classification (low, medium and high potential level of ellagitannin) and the ellagitannin content estimated by HPLC–UV was found. Each different group of NIRS classified staves was then added to red Wine during its Aging in a stainless tank, and the extraction and evolution of the ellagitannins were monitored. A good correlation between the NIRS classification and the concentration of ellagitannins in red Wine Aging in contact with the clas...
Ignacio Nevares - One of the best experts on this subject based on the ideXlab platform.
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artificial intelligence methods for constructing Wine barrels with a controlled oxygen transmission rate
Molecules, 2020Co-Authors: Victor Martinezmartinez, Ignacio Nevares, Maria Del AlamosanzaAbstract:Oxygen is an important factor in the Wine Aging process, and the oxygen transmission rate (OTR) is the parameter of the wood that reflects its oxygen permeation. OTR has not been considered in the cooperage industry yet; however, recent studies proposed a nondestructive method for estimating the OTR of barrel staves, but an efficient method to combine these staves to build barrels with a desired OTR is needed to implement it in the industry. This article proposes artificial intelligence methods for selecting staves for the construction of barrel heads or bodies with a desired target OTR. Genetic algorithms were used to implement these methods in consideration of the known OTR of the staves and the geometry of the Wine barrels. The proposed methods were evaluated in several scenarios: homogenizing the OTR of the actual constructed barrels, constructing low-OTR and high-OTR barrels based on a preclassification of the staves and implementing the proposed method in real cooperage conditions. The results of these experiments suggest the suitability of the proposed methods for their implementation in a cooperage in order to build controlled OTR barrels.
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oxygen consumption by red Wines under different micro oxygenation strategies and q pyrenaica chips effects on color and phenolic characteristics
Beverages, 2018Co-Authors: Rosario Sanchezgomez, Ignacio Nevares, Ana M Martinezgil, Maria Del AlamosanzaAbstract:The use of alternative oak products (AOP) for Wine Aging is a common practice in which micro-oxygenation (MOX) is a key factor to obtain a final Wine that is more stable over time and with similar characteristics as barrel-aged Wines. Therefore, the oxygen dosage added must be that which the Wine is able to consume to develop correctly. Oxygen consumption by red Wine determines its properties, so it is essential that micro-oxygenation be managed properly. This paper shows the results from the study of the influence on red Wine of two different MOX strategies: floating oxygen dosage (with dissolved oxygen setpoint of 50 µg/L) and fixed oxygen dosage (3 mL/L·month). The results indicated that the Wines consumed all the oxygen provided: those from fixed MOX received between 3 and 3.5 times more oxygen than the floating MOX strategy, the oxygen contribution from the air entrapped in the wood being more significant in the latter. Wines aged with wood and MOX showed the same color and phenolic evolution as those aged in barrels, demonstrating the importance of MOX management. Despite the differences in the oxygen consumed, it was not possible to differentiate Wines from the different MOX strategies at the end of the Aging period in contact with wood.
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micro oxygenation strategy depends on origin and size of oak chips or staves during accelerated red Wine Aging
Analytica Chimica Acta, 2010Co-Authors: Maria Del Alamo, Laura Gallego, Brigida Fernandez De Simon, Ignacio Nevares, Estrella CadahiaAbstract:Abstract The practice of Wine Aging in stainless steel tank involves storing Wine in contact with wood and dosing it with small oxygen quantities in order to obtain a final Wine more stable in time and with the same characteristics of barrel-aged Wines. Oxygen dosing is a key factor and, to achieve a correct development of Wine, needs to be applied according to Wine necessities and to the kind of wood chosen. This paper shows the results obtained from the study of oxygen required by a same Wine aged in tanks with different alternative products (chips and staves) made of American (Q. alba ), French (Q. petraea ) and Spanish oak (Q. pyrenaica ), with a strategy of micro-oxygenation as required. The results indicate that the size and origin of the wood used determine the oxygen management during the process. In fact, Wine treated with big pieces (staves) consumes more oxygen and, with regard to wood origin, Wine aged with French oak (Q. petraea ) products needs of a higher oxygen dosage.
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redox potential evolution during red Wine Aging in alternative systems
Analytica Chimica Acta, 2006Co-Authors: Maria Del Alamo, Ignacio Nevares, Luis Miguel Carcel CarcelAbstract:Abstract The variations of redox potential (EH) reflect the oxidation–reduction reactions happening to the Wine throughout its Aging period. The present study shows the evolution of redox potential in a red Wine during Aging in different systems (barrels, oak chips and oak staves). All of them have undergone by the same Aging conditions carried out in a Wine cellar participating the Cigales Appellation of Origin Program (Spain). The monitoring of EH, basic parameters, color parameters and phenolic compounds explains their modifications, as well as the correlations between the EH and these parameters with Aging time. The redox potential is a useful discriminant variable to differentiate Wine Aging systems.
Nuno Mateus - One of the best experts on this subject based on the ideXlab platform.
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Wine inspired chemistry anthocyanin transformations for a portfolio of natural colors
Synlett, 2017Co-Authors: Joana Oliveira, Nuno Mateus, Victor De FreitasAbstract:During Wine Aging and maturation, anthocyanins can react with flavanols (directly or mediated by aldehydes) and with small molecules derived from yeast metabolism during fermentation. It has been demonstrated that A-type vitisins (the main pyranoanthocyanins found in red Wines) can react with other Wine components yielding pyranoanthocyanin pigments with different colors ranging from yellow to turquoise blue. Wine-color chemistry has been an inspiration for the synthesis of new molecules with unique chromatic features. 1 Introduction 2 Formation of Anthocyanin Derivatives 3 Conclusion and Outlook
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Antioxidant Features of Red Wine Pyranoanthocyanins: Experimental and Theoretical Approaches
2014Co-Authors: Joana Azevedo, Victor De Freitas, Joana Oliveira, Luis Cruz, Natércia Teixeira, Natércia F. Brás, Nuno MateusAbstract:This work is focused on the study of the antioxidant properties of red Wine anthocyanin derivatives (carboxypyranoanthocyanins, methylpyranoanthocyanins, oxovitisins, and pyranoanthocyanin-phenolics) derived from malvidin-3-glucoside. Some antioxidant features were determined using the DPPH assay and the ability to delay lipid peroxidation in a liposome membrane system by monitoring oxygen consumption. The pyranoanthocyanin-phenolics have higher antioxidant potential than that of malvidin-3-glucoside, suggesting that the addition of a catechol or flavanol moiety increases the antioxidant capacity. The only derivatives that showed lower antioxidant features than malvidin-3-glucoside were oxovitisins and methylpyranomalvidin-3-glucoside. Also, the radical scavenging capacity of these pyranoanthocyanins was computationally explored using DFT methods. All pyranoanthocyanins were suggested as good candidates as antioxidant compounds because they easily donate an H atom to the free radicals, originating stable species. Altogether, these results support the fact that the antioxidant potential arising from anthocyanins is not impaired by some of their transformations during red Wine Aging
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reaction between hydroxycinnamic acids and anthocyanin pyruvic acid adducts yielding new portisins
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Joana Oliveira, Victor De Freitas, And Artur M S Silva, Nuno MateusAbstract:Three new anthocyanin-derived pigments were found to occur in a 2-year-old Port red Wine. Their structures were elucidated through LC/DAD-MS and NMR analysis and were found to correspond to a pyranoanthocyanin moiety linked to substituted cinnamyl substituents. The structures of these compounds are very similar to the one already reported for portisins, with a phenolic moiety replacing the catechin moiety. The newly formed anthocyanin-derived compounds display a bathochromic shift of the lambdamax ( approximately 540 nm) when compared with their anthocyanin-pyruvic acid adduct precursor (lambdamax = 511 nm), which may be due to the extended conjugation of the pi electrons in the structures of those pigments. Studies performed in model solutions helped to clarify the formation mechanism of these pigments that can result from the nucleophilic attack of the olefinic double bond of a hydroxycinnamic acid to the eletrophilic C-10 position of the anthocyanin-pyruvic acid adduct, followed by the loss of a formic acid molecule and decarboxylation. The chromatic characterization of these malvidin-3-glucoside-derived compounds revealed a higher resistance to discoloration against the nucleophilic attack by water and bisulfite when compared to malvidin-3-glucoside that is almost converted into its colorless hemiacetal form. However, the resistance to discoloration of these new pigments is not as high as the one reported for catechin-derived portisins. This could be explained by the presence of a smaller group (hydroxycinnamyl group), which does not protect so efficiently the chromophore against nucleophilic attack at the C-2 position. The occurrence of these pigments in red Wine highlights new chemical pathways involving anthocyanin-pyruvic acid derivatives as precursors for the formation of new pigments in subsequent stages of Wine Aging that may contribute to its color evolution.
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a new class of blue anthocyanin derived pigments isolated from red Wines
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Nuno Mateus, Celestino Santosbuelga, Julian C Rivasgonzalo, Victor De FreitasAbstract:Two newly formed anthocyanin-derived pigments that revealed unique spectroscopic features, showing maximum absorption in their UV−vis spectra at 575 nm, were isolated by TSK Toyopearl HW-40 (S) gel column chromatography and semipreparative HPLC from an aged Port red Wine. Further characterization by ESI/MS and NMR (1H, gCOSY) showed them to belong to a new class of pigments described here for the first time, the structure of which consisted of a pyranoanthocyanin moiety linked to a flavanol by a vinyl bridge. The extended conjugation of the π electrons throughout all the pigment molecule is likely to confer a higher stability on it and is probably the origin of the intense blue color. The formation of these pigments was found to arise from the reaction between anthocyanin−pyruvic acid adducts and vinyl−flavanol adducts. Keywords: Pyranoanthocyanin; flavanols; red Wine; Aging; blue color
