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Philippe Darriet - One of the best experts on this subject based on the ideXlab platform.
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Influence of Chirality of Lactones on the Perception of Some Typical Fruity Notes through Perceptual Interaction Phenomena in Bordeaux Dessert Wines.
Journal of agricultural and food chemistry, 2016Co-Authors: Panagiotis Stamatopoulos, Eric Brohan, Céline Prevost, Markus Herderich, Tracey Siebert, Philippe DarrietAbstract:Recent studies concerning the aroma of noble rot Dessert Wines revealed the importance of a well-known phenomenon in perfumery, the perceptual blending, to create the perception of “overripe orange” nuances. Thus, compounds associated with both oak wood aging (3-methyl-4-octanolide and eugenol) and Botrytis cinerea development under the form of noble rot (2-nonen-4-olide and γ-nonalactone) contribute to a specific aroma of great noble rot Dessert Wines through perceptual interaction phenomena. This synthetic perception phenomenon was established from reconstitution, addition, and omission sensory experiments, using wine extract fractions supplemented with the volatile compounds previously mentioned. To better understand the sensory impact of these compounds, the goal of this research was to study the contributions of enantiomeric forms of 2-nonen-4-olide and γ-nonalactone and the diastereoisomers of 3-methyl-4-octanolide. After multidimensional chiral chromatography analysis, the relative proportions of e...
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Influence of chirality of lactones on the perception of some typical fruity notes through perceptual interaction phenomena in Bordeaux Dessert Wines
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Panagiotis Stamatopoulos, Eric Brohan, Céline Prevost, Tracey E. Siebert, Markus Herderich, Philippe DarrietAbstract:Recent studies concerning the aroma of noble rot Dessert Wines revealed the importance of a well-known phenomenon in perfumery, the perceptual blending, to create the perception of "overripe orange" nuances. Thus, compounds associated with both oak wood aging (3-methyl-4-octanolide and eugenol) and Botiytis cinerea development under the form of noble rot (2-nonen-4-olide and gamma-nonalactone) contribute to a specific aroma of great noble rot Dessert Wines through perceptual interaction phenomena. This synthetic perception phenomenon was established from reconstitution, addition, and omission sensory experiments, using wine extract fractions supplemented with the volatile compounds previously mentioned. To better understand the sensory impact of these compounds, the goal of this research was to study the contributions of enantiomeric forms of 2-nonen-4-olide and gamma-nonalactone and the diastereoisomers of 3-methyl-4-octanolide. After multidimensional chiral chromatography-analysis, the relative proportions of enantiomers or diastereomeric forms were first established and then sensory experiments were carried out using the reference compounds with isolated fractions from Dessert Wines. A dominance of the R form was established for 2-nonen-4-olide, which was correlated with wine aging, while the S form is more dominant in young Dessert Wines. Furthermore, the reconstitution experiments confirmed perceptual interaction phenomena and revealed the sensory contribution of (R)-2-nonen-4-olide and cis-3-methyl-4-octanolide concerning the "overripe orange" nuances, whereas no sensory impact for the gamma-nonalactone isomers was observed.
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Evidence for perceptual interaction phenomena to interpret typical nuances of “overripe” fruity aroma in Bordeaux Dessert Wines
2015Co-Authors: Panagiotis Stamatopoulos, Eric Frerot, Philippe DarrietAbstract:Bordeaux Dessert Wines can present a complex flavor, recalling overripe fruits, featuring citrus, especially orange notes. It was not possible to identify the volatile compounds responsible for these typical notes using traditional strategies, i.e. analysis of wine extracts by GC-olfactometry (GC-O). Thus a new strategy, combining both analytical and sensory approaches, was applied to fractions obtained by semi-preparative HPLC of wine extracts. Then omission tests, using preparative GC with cryotrapping, were used to identify fractions presenting overripe fruit nuances, particularly orange notes. Finally, multidimensional GC/MS-O was applied to these fractions to identify a new lactone, specific to Dessert Wines. While this compound presents minty and fruity nuances, it was found to contribute, together with other wine volatile compounds, to some typical nuances in Bordeaux Wines, particularly Sauternes, via perceptual interaction phenomena.
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identification of a new lactone contributing to overripe orange aroma in bordeaux Dessert Wines via perceptual interaction phenomena
Journal of Agricultural and Food Chemistry, 2014Co-Authors: Panagiotis Stamatopoulos, Eric Frerot, Sophie Tempere, Alexandre Pons, Philippe DarrietAbstract:Recent studies have demonstrated the existence of a typical sensory concept for Bordeaux Dessert Wines, including the world famous Wines of Sauternes. Volatile compounds from several chemical families (thiols, aldehydes, and lactones) were identified and correlated with aromatic typicality in these Wines. However, these studies were unable to indicate “key” aromas of overripe fruits, especially overripe orange. The alternative strategy developed in this research combined both analytical and sensory studies of fractions of Dessert wine extracts obtained by semipreparative high-performance liquid chromatography (HPLC). Multidimensional gas chromatography coupled to olfactometry and mass spectrometry (MDGC-O/MS) was applied to some of the HPLC fractions recalling “overripe fruit”, and a new lactone, 2-nonen-4-olide, was identified. Reconstitution and omission tests using the HPLC fractions highlighted the importance of specific compounds, particularly 2-nonen-4-olide, in the expression of overripe orange not...
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Identification of a new lactone contributing to overripe orange aroma in Bordeaux Dessert Wines via perceptual interaction phenomena
Journal of Agricultural and Food Chemistry, 2014Co-Authors: Panagiotis Stamatopoulos, Eric Frerot, Sophie Tempere, Alexandre Pons, Philippe DarrietAbstract:Recent studies have demonstrated the existence of a typical sensory concept for Bordeaux Dessert Wines, including the world famous Wines of Sauternes. Volatile compounds from several chemical families (thiols, aldehydes, and lactones) were identified and correlated with aromatic typicality in these Wines. However, these studies were unable to indicate "key" aromas of overripe fruits, especially overripe orange. The alternative strategy developed in this research combined both analytical and sensory studies of fractions of Dessert wine extracts obtained by semipreparative high-performance liquid chromatography (HPLC). Multidimensional gas chromatography coupled to olfactometry and mass spectrometry (MDGC-O/MS) was applied to some of the HPLC fractions recalling "overripe fruit", and a new lactone, 2-nonen-4-olide, was identified. Reconstitution and omission tests using the HPLC fractions highlighted the importance of specific compounds, particularly 2-nonen-4-olide, in the expression of overripe orange notes. Although this lactone presents minty and fruity odors, its key contribution to the typical aroma of orange in Bordeaux Dessert Wines was revealed through perceptual blending.
Panagiotis Stamatopoulos - One of the best experts on this subject based on the ideXlab platform.
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Influence of Chirality of Lactones on the Perception of Some Typical Fruity Notes through Perceptual Interaction Phenomena in Bordeaux Dessert Wines.
Journal of agricultural and food chemistry, 2016Co-Authors: Panagiotis Stamatopoulos, Eric Brohan, Céline Prevost, Markus Herderich, Tracey Siebert, Philippe DarrietAbstract:Recent studies concerning the aroma of noble rot Dessert Wines revealed the importance of a well-known phenomenon in perfumery, the perceptual blending, to create the perception of “overripe orange” nuances. Thus, compounds associated with both oak wood aging (3-methyl-4-octanolide and eugenol) and Botrytis cinerea development under the form of noble rot (2-nonen-4-olide and γ-nonalactone) contribute to a specific aroma of great noble rot Dessert Wines through perceptual interaction phenomena. This synthetic perception phenomenon was established from reconstitution, addition, and omission sensory experiments, using wine extract fractions supplemented with the volatile compounds previously mentioned. To better understand the sensory impact of these compounds, the goal of this research was to study the contributions of enantiomeric forms of 2-nonen-4-olide and γ-nonalactone and the diastereoisomers of 3-methyl-4-octanolide. After multidimensional chiral chromatography analysis, the relative proportions of e...
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Influence of chirality of lactones on the perception of some typical fruity notes through perceptual interaction phenomena in Bordeaux Dessert Wines
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Panagiotis Stamatopoulos, Eric Brohan, Céline Prevost, Tracey E. Siebert, Markus Herderich, Philippe DarrietAbstract:Recent studies concerning the aroma of noble rot Dessert Wines revealed the importance of a well-known phenomenon in perfumery, the perceptual blending, to create the perception of "overripe orange" nuances. Thus, compounds associated with both oak wood aging (3-methyl-4-octanolide and eugenol) and Botiytis cinerea development under the form of noble rot (2-nonen-4-olide and gamma-nonalactone) contribute to a specific aroma of great noble rot Dessert Wines through perceptual interaction phenomena. This synthetic perception phenomenon was established from reconstitution, addition, and omission sensory experiments, using wine extract fractions supplemented with the volatile compounds previously mentioned. To better understand the sensory impact of these compounds, the goal of this research was to study the contributions of enantiomeric forms of 2-nonen-4-olide and gamma-nonalactone and the diastereoisomers of 3-methyl-4-octanolide. After multidimensional chiral chromatography-analysis, the relative proportions of enantiomers or diastereomeric forms were first established and then sensory experiments were carried out using the reference compounds with isolated fractions from Dessert Wines. A dominance of the R form was established for 2-nonen-4-olide, which was correlated with wine aging, while the S form is more dominant in young Dessert Wines. Furthermore, the reconstitution experiments confirmed perceptual interaction phenomena and revealed the sensory contribution of (R)-2-nonen-4-olide and cis-3-methyl-4-octanolide concerning the "overripe orange" nuances, whereas no sensory impact for the gamma-nonalactone isomers was observed.
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Evidence for perceptual interaction phenomena to interpret typical nuances of “overripe” fruity aroma in Bordeaux Dessert Wines
2015Co-Authors: Panagiotis Stamatopoulos, Eric Frerot, Philippe DarrietAbstract:Bordeaux Dessert Wines can present a complex flavor, recalling overripe fruits, featuring citrus, especially orange notes. It was not possible to identify the volatile compounds responsible for these typical notes using traditional strategies, i.e. analysis of wine extracts by GC-olfactometry (GC-O). Thus a new strategy, combining both analytical and sensory approaches, was applied to fractions obtained by semi-preparative HPLC of wine extracts. Then omission tests, using preparative GC with cryotrapping, were used to identify fractions presenting overripe fruit nuances, particularly orange notes. Finally, multidimensional GC/MS-O was applied to these fractions to identify a new lactone, specific to Dessert Wines. While this compound presents minty and fruity nuances, it was found to contribute, together with other wine volatile compounds, to some typical nuances in Bordeaux Wines, particularly Sauternes, via perceptual interaction phenomena.
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identification of a new lactone contributing to overripe orange aroma in bordeaux Dessert Wines via perceptual interaction phenomena
Journal of Agricultural and Food Chemistry, 2014Co-Authors: Panagiotis Stamatopoulos, Eric Frerot, Sophie Tempere, Alexandre Pons, Philippe DarrietAbstract:Recent studies have demonstrated the existence of a typical sensory concept for Bordeaux Dessert Wines, including the world famous Wines of Sauternes. Volatile compounds from several chemical families (thiols, aldehydes, and lactones) were identified and correlated with aromatic typicality in these Wines. However, these studies were unable to indicate “key” aromas of overripe fruits, especially overripe orange. The alternative strategy developed in this research combined both analytical and sensory studies of fractions of Dessert wine extracts obtained by semipreparative high-performance liquid chromatography (HPLC). Multidimensional gas chromatography coupled to olfactometry and mass spectrometry (MDGC-O/MS) was applied to some of the HPLC fractions recalling “overripe fruit”, and a new lactone, 2-nonen-4-olide, was identified. Reconstitution and omission tests using the HPLC fractions highlighted the importance of specific compounds, particularly 2-nonen-4-olide, in the expression of overripe orange not...
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Identification of a new lactone contributing to overripe orange aroma in Bordeaux Dessert Wines via perceptual interaction phenomena
Journal of Agricultural and Food Chemistry, 2014Co-Authors: Panagiotis Stamatopoulos, Eric Frerot, Sophie Tempere, Alexandre Pons, Philippe DarrietAbstract:Recent studies have demonstrated the existence of a typical sensory concept for Bordeaux Dessert Wines, including the world famous Wines of Sauternes. Volatile compounds from several chemical families (thiols, aldehydes, and lactones) were identified and correlated with aromatic typicality in these Wines. However, these studies were unable to indicate "key" aromas of overripe fruits, especially overripe orange. The alternative strategy developed in this research combined both analytical and sensory studies of fractions of Dessert wine extracts obtained by semipreparative high-performance liquid chromatography (HPLC). Multidimensional gas chromatography coupled to olfactometry and mass spectrometry (MDGC-O/MS) was applied to some of the HPLC fractions recalling "overripe fruit", and a new lactone, 2-nonen-4-olide, was identified. Reconstitution and omission tests using the HPLC fractions highlighted the importance of specific compounds, particularly 2-nonen-4-olide, in the expression of overripe orange notes. Although this lactone presents minty and fruity odors, its key contribution to the typical aroma of orange in Bordeaux Dessert Wines was revealed through perceptual blending.
Vincenzo Gerbi - One of the best experts on this subject based on the ideXlab platform.
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ciel a b parameters of white dehydrated grapes as quality markers according to chemical composition volatile profile and mechanical properties
Analytica Chimica Acta, 2012Co-Authors: Luca Giorgio Carlo Rolle, Manuela Giordano, Simone Giacosa, Simone Vincenzi, Susana Rio Segade, Fabrizio Torchio, Benedetta Perrone, Vincenzo GerbiAbstract:Abstract In the oenological sector, the withering process is of particular importance in the production of dry and sweet Dessert Wines due to the total or partial use of overripe and/or dehydrated grapes. This complex process leads to several changes in the chemical–physical characteristics of white grape berries affecting the wine quality and, at the end of the dehydration period, different visual attributes are usually present in the berry skins. The aim of this work, therefore, was to study the properties of Erbaluce dried grapes of varying external colors, classified into three groups based on reflectance colorimetry (green, gold and blue). The chemical composition, volatile profile and mechanical attributes were investigated, focusing on establishing relationships between CIEL* a * b * parameters of dehydrated grapes and their chemical–physical characteristics. The higher values of the glucose–fructose ratio, together with the higher content of sugars, gluconic acid and glycerol, but lower titratable acidity, suggests the presence of Botrytis cinerea Pers. infection in blue withered berries, which has been microbiologically confirmed. Regarding the instrumental mechanical properties, blue dehydrated grapes were characterized by a lower skin hardness and higher skin thickness in agreement with the higher weight loss experienced. Finally, the determination of free and bound volatile compounds showed that some of them were only found in blue withered berries, δ-lactones being considered the main chemical markers of the noble rot infection that are important for the odor character. C-10 alkyl massoia lactone was the most abundant volatile compound in blue botrytized grapes.
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CIEL*a*b* parameters of white dehydrated grapes as quality markers according to chemical composition, volatile profile and mechanical properties.
Analytica chimica acta, 2011Co-Authors: Luca Giorgio Carlo Rolle, Manuela Giordano, Simone Giacosa, Simone Vincenzi, Susana Rio Segade, Fabrizio Torchio, Benedetta Perrone, Vincenzo GerbiAbstract:Abstract In the oenological sector, the withering process is of particular importance in the production of dry and sweet Dessert Wines due to the total or partial use of overripe and/or dehydrated grapes. This complex process leads to several changes in the chemical–physical characteristics of white grape berries affecting the wine quality and, at the end of the dehydration period, different visual attributes are usually present in the berry skins. The aim of this work, therefore, was to study the properties of Erbaluce dried grapes of varying external colors, classified into three groups based on reflectance colorimetry (green, gold and blue). The chemical composition, volatile profile and mechanical attributes were investigated, focusing on establishing relationships between CIEL* a * b * parameters of dehydrated grapes and their chemical–physical characteristics. The higher values of the glucose–fructose ratio, together with the higher content of sugars, gluconic acid and glycerol, but lower titratable acidity, suggests the presence of Botrytis cinerea Pers. infection in blue withered berries, which has been microbiologically confirmed. Regarding the instrumental mechanical properties, blue dehydrated grapes were characterized by a lower skin hardness and higher skin thickness in agreement with the higher weight loss experienced. Finally, the determination of free and bound volatile compounds showed that some of them were only found in blue withered berries, δ-lactones being considered the main chemical markers of the noble rot infection that are important for the odor character. C-10 alkyl massoia lactone was the most abundant volatile compound in blue botrytized grapes.
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Chemical and volatile composition of three italian sweet white Passito Wines
OENO One, 2009Co-Authors: Manuela Giordano, Luca Giorgio Carlo Rolle, Giuseppe Zeppa, Vincenzo GerbiAbstract:Aims: This study was designed to gain knowledge of three Controlled Denomination of Origin (DOC) Italian sweet white Passito Wines (Caluso Passito DOC, Cinque Terre Sciacchetra DOC and Passito di Pantelleria DOC) produced in several areas of Italy from grapes dried with different systems and vinification techniques. Methods and results: Physico-chemical and chromatic characteristics, sodium, potassium, gluconic acid, glucono- γ-lactone, acetaldehyde, sorbitol, laccase, organic acids and semi-quantitative free volatile profile were determined on these Wines. Caluso Passito DOC Wines presented higher contents of organic acids (above all, malic acid), main metabolites from noble Botrytis cinerea (laccase, glycerol, gluconic acid and benzaldehyde) and low contents of total polyphenols. Among the volatile components, normal fatty acid ethyl esters (ethyl hexanoate and ethyl octanoate), branched-chain esters (ethyl 2-methylpropanoate, ethyl 2-methylbutyrate, ethyl 3-methylbutyrate) and benzaldeyde characterized this Passito wine. Cinque Terre Sciacchetra DOC Wines showed the lowest total acidity with a lower amount of malic acid and a higher content of polyphenols. This wine was characterized by some predominant acetates (isoamyl acetate), alcohols, benzaldehyde and an isoprenoid, s-damascenone. Passito di Pantelleria DOC Wines presented higher amounts of ashes resulting in higher pH values compared to the other two Passito typologies. Due to its production from aromatic grapes, it showed several varietal components such as terpenes, while ethyl esters/acetates and alcohols were less represented. Conclusion: This survey provides information allowing the characterisation of three Passito Dessert Wines at high commercial value. Significance and impact of the study: This study provides oenological information to be utilised to protect and valorise the Controlled Denomination of Origin sweet wine production and contributes to the preservation of traditional and terroir productions and their commercialization.
Luca Giorgio Carlo Rolle - One of the best experts on this subject based on the ideXlab platform.
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ciel a b parameters of white dehydrated grapes as quality markers according to chemical composition volatile profile and mechanical properties
Analytica Chimica Acta, 2012Co-Authors: Luca Giorgio Carlo Rolle, Manuela Giordano, Simone Giacosa, Simone Vincenzi, Susana Rio Segade, Fabrizio Torchio, Benedetta Perrone, Vincenzo GerbiAbstract:Abstract In the oenological sector, the withering process is of particular importance in the production of dry and sweet Dessert Wines due to the total or partial use of overripe and/or dehydrated grapes. This complex process leads to several changes in the chemical–physical characteristics of white grape berries affecting the wine quality and, at the end of the dehydration period, different visual attributes are usually present in the berry skins. The aim of this work, therefore, was to study the properties of Erbaluce dried grapes of varying external colors, classified into three groups based on reflectance colorimetry (green, gold and blue). The chemical composition, volatile profile and mechanical attributes were investigated, focusing on establishing relationships between CIEL* a * b * parameters of dehydrated grapes and their chemical–physical characteristics. The higher values of the glucose–fructose ratio, together with the higher content of sugars, gluconic acid and glycerol, but lower titratable acidity, suggests the presence of Botrytis cinerea Pers. infection in blue withered berries, which has been microbiologically confirmed. Regarding the instrumental mechanical properties, blue dehydrated grapes were characterized by a lower skin hardness and higher skin thickness in agreement with the higher weight loss experienced. Finally, the determination of free and bound volatile compounds showed that some of them were only found in blue withered berries, δ-lactones being considered the main chemical markers of the noble rot infection that are important for the odor character. C-10 alkyl massoia lactone was the most abundant volatile compound in blue botrytized grapes.
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CIEL*a*b* parameters of white dehydrated grapes as quality markers according to chemical composition, volatile profile and mechanical properties.
Analytica chimica acta, 2011Co-Authors: Luca Giorgio Carlo Rolle, Manuela Giordano, Simone Giacosa, Simone Vincenzi, Susana Rio Segade, Fabrizio Torchio, Benedetta Perrone, Vincenzo GerbiAbstract:Abstract In the oenological sector, the withering process is of particular importance in the production of dry and sweet Dessert Wines due to the total or partial use of overripe and/or dehydrated grapes. This complex process leads to several changes in the chemical–physical characteristics of white grape berries affecting the wine quality and, at the end of the dehydration period, different visual attributes are usually present in the berry skins. The aim of this work, therefore, was to study the properties of Erbaluce dried grapes of varying external colors, classified into three groups based on reflectance colorimetry (green, gold and blue). The chemical composition, volatile profile and mechanical attributes were investigated, focusing on establishing relationships between CIEL* a * b * parameters of dehydrated grapes and their chemical–physical characteristics. The higher values of the glucose–fructose ratio, together with the higher content of sugars, gluconic acid and glycerol, but lower titratable acidity, suggests the presence of Botrytis cinerea Pers. infection in blue withered berries, which has been microbiologically confirmed. Regarding the instrumental mechanical properties, blue dehydrated grapes were characterized by a lower skin hardness and higher skin thickness in agreement with the higher weight loss experienced. Finally, the determination of free and bound volatile compounds showed that some of them were only found in blue withered berries, δ-lactones being considered the main chemical markers of the noble rot infection that are important for the odor character. C-10 alkyl massoia lactone was the most abundant volatile compound in blue botrytized grapes.
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Chemical and volatile composition of three italian sweet white Passito Wines
OENO One, 2009Co-Authors: Manuela Giordano, Luca Giorgio Carlo Rolle, Giuseppe Zeppa, Vincenzo GerbiAbstract:Aims: This study was designed to gain knowledge of three Controlled Denomination of Origin (DOC) Italian sweet white Passito Wines (Caluso Passito DOC, Cinque Terre Sciacchetra DOC and Passito di Pantelleria DOC) produced in several areas of Italy from grapes dried with different systems and vinification techniques. Methods and results: Physico-chemical and chromatic characteristics, sodium, potassium, gluconic acid, glucono- γ-lactone, acetaldehyde, sorbitol, laccase, organic acids and semi-quantitative free volatile profile were determined on these Wines. Caluso Passito DOC Wines presented higher contents of organic acids (above all, malic acid), main metabolites from noble Botrytis cinerea (laccase, glycerol, gluconic acid and benzaldehyde) and low contents of total polyphenols. Among the volatile components, normal fatty acid ethyl esters (ethyl hexanoate and ethyl octanoate), branched-chain esters (ethyl 2-methylpropanoate, ethyl 2-methylbutyrate, ethyl 3-methylbutyrate) and benzaldeyde characterized this Passito wine. Cinque Terre Sciacchetra DOC Wines showed the lowest total acidity with a lower amount of malic acid and a higher content of polyphenols. This wine was characterized by some predominant acetates (isoamyl acetate), alcohols, benzaldehyde and an isoprenoid, s-damascenone. Passito di Pantelleria DOC Wines presented higher amounts of ashes resulting in higher pH values compared to the other two Passito typologies. Due to its production from aromatic grapes, it showed several varietal components such as terpenes, while ethyl esters/acetates and alcohols were less represented. Conclusion: This survey provides information allowing the characterisation of three Passito Dessert Wines at high commercial value. Significance and impact of the study: This study provides oenological information to be utilised to protect and valorise the Controlled Denomination of Origin sweet wine production and contributes to the preservation of traditional and terroir productions and their commercialization.
Maria Rosário Bronze - One of the best experts on this subject based on the ideXlab platform.
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Application of FTIR-ATR to Moscatel Dessert Wines for prediction of total phenolic and flavonoid contents and antioxidant capacity.
Food chemistry, 2013Co-Authors: Sandra D. Silva, Rodrigo P. Feliciano, Luís Vilas Boas, Maria Rosário BronzeAbstract:Abstract Fourier transform infrared spectroscopy (FTIR) attenuated total reflectance (ATR) was applied for the determination of total phenolic and flavonoid contents and antioxidant capacity (DPPH and FRAP assays) in Moscatel Dessert Wines ( n = 56). Prediction models were developed for the referred parameters using Partial Least Squares (PLS) considering the spectral region 1800–900 cm −1 . The determination coefficients ( r 2 ) values in the calibration models ranged from 0.670 to 0.870. Cross validation (leave-one-out technique) was applied to the data. Root mean square errors of calibration (RMSEC) and cross validation (RMSECV) as well as the relative errors of prediction (REP) were calculated. Minimum errors of prediction were obtained for total flavonoid content (0.2%) and maximum values (22%) for antioxidant capacity measured by FRAP. The proposed method may be used for rapid screening of total phenolic and flavonoid contents in Moscatel Dessert Wines. The implemented methodologies may also be used to get rough estimates for DPPH and FRAP antioxidant capacities.
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Phenolic Content and Antioxidant Activity of Moscatel Dessert Wines from the Setúbal Region in Portugal
Food Analytical Methods, 2009Co-Authors: Rodrigo P. Feliciano, Luís Vilas Boas, Maria N. Bravo, Marilda M. Pires, Ana T. Serra, Catarina M. Duarte, Maria Rosário BronzeAbstract:Moscatel Wines from Setúbal were analyzed for their total phenolic (mean value 1,243 mg gallic acid equivalents/L), and total flavonoid (mean value 248 mg catechin/L) composition by spectrophotometric and chromatographic methods were used to quantify phenolic compounds as benzoic acids, cinnamic acids, stilbens, and some flavonoids. Antioxidant activity of the Wines was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH; mean value 70.7% inhibition), ferric reducing antioxidant power (FRAP; mean value 3,098 mg of Trolox equivalents/L) and oxygen radical absorbance capacity (ORAC; mean value 10,724 μmol/L) assays. Results were analyzed using principal component analysis which allowed samples to be grouped in terms of both winemaking producer and vintage. By plotting correlation loadings, it was possible to understand which variables were responsible for sample distribution. The correlation between results obtained for variables show that, in general, total flavonoid content is a better estimation of antioxidant activity in Moscatel samples ( r _ORAC/flavonoids = 0.832, r _FRAP/flavonoids = 0.677) than total phenolic content ( r _ORAC/phenolics = 0.680, r _FRAP/phenolics = 0.372). No major correlations were detected for DPPH assay results ( r _DPPH/flavonoids = 0.283, r _DPPH/phenolics = 0.271). Chromatographic profiles showed important differences among Moscatel Wines. Gallic acid contents and results of antioxidant activity tests were strongly correlated ( r values in the range 0.74–0.92). Correlations of the results obtained for antioxidant activity tests with contents of other phenolic compounds such as ethyl caffeate, ethyl gallate, caffeic acid, protocatechuic acid, and t -caftaric acid depend on sample and type of test employed.