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Michael Moutounet - One of the best experts on this subject based on the ideXlab platform.

  • extraction of phenolics in liquid model matrices containing Oak Chips kinetics liquid chromatography mass spectroscopy characterisation and association with in vitro antiradical activity
    Food Chemistry, 2008
    Co-Authors: Evangelia Karvela, Dimitris P Makris, Panagiotis Kefalas, Michael Moutounet
    Abstract:

    Four different liquid model matrices were utilised to study the leaching of polyphenols from Oak Chips. The matrices included distilled water, 12% (v/v) ethanol, 12% (v/v) ethanol adjusted to pH 3.4, and 55% (v/v) ethanol. Extraction of phenolics into the liquid systems was monitored by the estimation of the total polyphenol concentration, using the Folin-Ciocalteu method. The in vitro antiradical activity was also recorded using the stable DPPH radical, to ascertain enrichment of the solutions with potentially antioxidant compounds. As a final step, the polyphenolic composition of each matrix was characterised by means of liquid chromatography-electrospray ionisation mass spectrometry. The kinetics of polyphenol leaching into the liquid phase was found to obey a 2nd parameter power equation of the type y=ax(b), which produced a good fit of the data (p<0.0001). Kinetics was faster in distilled water up to a point, where after polyphenol extraction occurred at higher rate in the 55% ethanolic solution. The antiradical activity in all cases was highly correlated with total polyphenol concentration (p<0.001), providing that the amount of polyphenols extracted into the liquid media exerted a proportional antioxidant effect. The analytical examination by liquid chromatography-mass spectrometry revealed that the compounds implicated are hydrolysable tannins and hydrolysis products thereof.

  • Extraction of phenolics in liquid model matrices containing Oak Chips: Kinetics, liquid chromatography–mass spectroscopy characterisation and association with in vitro antiradical activity
    Food Chemistry, 2008
    Co-Authors: Evangelia Karvela, Dimitris P Makris, Panagiotis Kefalas, Michael Moutounet
    Abstract:

    Four different liquid model matrices were utilised to study the leaching of polyphenols from Oak Chips. The matrices included distilled water, 12% (v/v) ethanol, 12% (v/v) ethanol adjusted to pH 3.4, and 55% (v/v) ethanol. Extraction of phenolics into the liquid systems was monitored by the estimation of the total polyphenol concentration, using the Folin-Ciocalteu method. The in vitro antiradical activity was also recorded using the stable DPPH radical, to ascertain enrichment of the solutions with potentially antioxidant compounds. As a final step, the polyphenolic composition of each matrix was characterised by means of liquid chromatography-electrospray ionisation mass spectrometry. The kinetics of polyphenol leaching into the liquid phase was found to obey a 2nd parameter power equation of the type y=ax(b), which produced a good fit of the data (p

  • Extraction of phenolics in liquid model matrices containing Oak Chips: kinetics, liquid chromatography–mass spectroscopy characterisation and association with in vitro antiradical activity
    Food Chemistry, 2008
    Co-Authors: Evangelia Karvela, Dimitris P Makris, Panagiotis Kefalas, Michael Moutounet
    Abstract:

    Four different liquid model matrices were utilised to study the leaching of polyphenols from Oak Chips. The matrices included distilled water, 12%, (v/v) ethanol, 12% (v/v) ethanol adjusted to pH 3.4, and 55% (v/v) ethanol. Extraction of phenolics into the liquid systems was monitored by the estimation of the total polyphenol concentration, using the Folin-Ciocalteu method. The in vitro antiradical activity was also recorded using the stable DPPH- radical, to ascertain enrichment of the solutions with potentially antioxidant compounds. As a final step, the polyphenolic composition of each matrix was characterised by means of liquid chromatography-clectrospray ionisation mass spectrometry. The kinetics of polyphenol leaching into the liquid phase was found to obey a 2nd parameter power equation of the type y = ax(b), which produced a good fit of the data (p < 0.0001). Kinetics was faster in distilled water up to a point, where after polyplienol extraction occurred at higher rate in the 55% ethanolic solution. The antiradical activity in all cases was highly correlated with total polyphenol concentration (p < 0.001), providing that the amount of polyphenols extracted into the liquid media exerted a proportional antioxidant effect. The analytical examination by liquid chromatography-mass spectrometry revealed that the compounds implicated are hydrolysable tannins and hydrolysis products thereof

M Gonzalez A Vinas - One of the best experts on this subject based on the ideXlab platform.

  • volatile composition of bobal red wines subjected to alcoholic malolactic fermentation with Oak Chips
    Lwt - Food Science and Technology, 2014
    Co-Authors: Gomez E Garciacarpintero, E Sanchezpalomo, M Gonzalez A Vinas
    Abstract:

    Abstract The effect of wood, in the form of Oak Chips, on the volatile composition of Bobal red wines caused by adding Oak Chips at different stages of the fermentation process has been studied. Aroma compounds were isolated by solid phase extraction (SPE) for subsequent analysis by gas chromatography–mass spectrometry (GC/MS). Bobal control wine was produced according to traditional winemaking processes, without Oak Chips. Oak Chips were added to the rest of the wines at two dose levels (3 and 6 g/L) at different stages of the winemaking process: at one week during alcoholic fermentation (AF), during malolactic fermentation (MLF) and in young, red Bobal wine. Wines fermented with Oak Chips during AF showed higher concentrations of the ethyl esters of straight-chain fatty acids and ethyl, hexyl and isoamyl acetates than the control wine. A similar, trend was observed for higher alcohols. Higher concentrations of benzene compounds, Oak lactones and furanic compounds were found in wines in contact with Oak Chips during MLF followed by young Bobal Oak wines. These results reveal that the point of addition during the winemaking process and the dose level of Oak Chips used have a significant effect on the volatile composition of Bobal red wines.

  • Volatile composition of Bobal red wines subjected to alcoholic/malolactic fermentation with Oak Chips
    Lwt - Food Science and Technology, 2014
    Co-Authors: E. G. García-carpintero, Eva Sánchez-palomo, M Gonzalez A Vinas
    Abstract:

    Abstract The effect of wood, in the form of Oak Chips, on the volatile composition of Bobal red wines caused by adding Oak Chips at different stages of the fermentation process has been studied. Aroma compounds were isolated by solid phase extraction (SPE) for subsequent analysis by gas chromatography–mass spectrometry (GC/MS). Bobal control wine was produced according to traditional winemaking processes, without Oak Chips. Oak Chips were added to the rest of the wines at two dose levels (3 and 6 g/L) at different stages of the winemaking process: at one week during alcoholic fermentation (AF), during malolactic fermentation (MLF) and in young, red Bobal wine. Wines fermented with Oak Chips during AF showed higher concentrations of the ethyl esters of straight-chain fatty acids and ethyl, hexyl and isoamyl acetates than the control wine. A similar, trend was observed for higher alcohols. Higher concentrations of benzene compounds, Oak lactones and furanic compounds were found in wines in contact with Oak Chips during MLF followed by young Bobal Oak wines. These results reveal that the point of addition during the winemaking process and the dose level of Oak Chips used have a significant effect on the volatile composition of Bobal red wines.

  • impact of alternative technique to ageing using Oak Chips in alcoholic or in malolactic fermentation on volatile and sensory composition of red wines
    Food Chemistry, 2012
    Co-Authors: Gomez E Garciacarpintero, M Gomez A Gallego, E Sanchezpalomo, M Gonzalez A Vinas
    Abstract:

    This paper reports on a complete study of the effect of wood, in the form of Oak Chips, on the volatile composition and sensory characteristics of Moravia Agria wines added at different stages of the fermentation process. Aroma compounds were analyzed by gas chromatography–mass spectrometry (GC–MS). Sensory profile was evaluated by experienced wine-testers. Oak Chips were added to wines in two dose rates at different stages of the winemaking process: during alcoholic fermentation (AF), during malolactic fermentation (MLF) and in young, red Moravia Agria wine. Wines fermented with Oak Chips during AF showed higher concentrations of the ethyl esters of straight-chain fatty acids, ethyl, hexyl, isoamyl acetates and superior alcohols than the control wines. The higher concentrations of benzene compound, Oak lactones and furanic compounds were found in wines in contact with Oak Chips during MLF. The use of Oak Chips gives rise to a different sensorial profile of wines depending of the point of addition. Higher intensities of woody, coconut, vanilla and sweet spices descriptors were obtained when a large dose rate of Chips was employed.

Andrey Legin - One of the best experts on this subject based on the ideXlab platform.

  • measurements of the effects of wine maceration with Oak Chips using an electronic tongue
    Food Chemistry, 2017
    Co-Authors: Alisa Rudnitskaya, Leigh Schmidtke, Ana Reis, Rosario M M Domingues, Ivonne Delgadillo, Bruno Debus, Dmitry Kirsanov, Andrey Legin
    Abstract:

    Abstract The use of Oak products as a cheaper alternative to expensive wood barrels was recently permitted in Europe, which led to a continuous increase in the use of Oak Chips and staves in winemaking. The feasibility of the potentiometric electronic tongue as a tool for monitoring the effects of wine maceration with Oak Chips was evaluated. Four types of commercially available Oak Chips subjected to different thermal treatments and washing procedures and their mixture were studied. Ethanolic extracts of the Chips were analysed using electrospray mass spectrometry and 28 phenolic and furanic compounds were identified. The electronic tongue comprising 22 potentiometric chemical sensors could distinguish artificial wine solutions and Cabernet Sauvignon wine macerated with different types of Oak Chips, quantify total and non-flavonoid phenolic content, as well as the concentrations of added Oak Chips. Using measurements at two pH levels, 3.2 and 6.5, improved the accuracy of quantification.

  • study of the influence of micro oxygenation and Oak chip maceration on wine composition using an electronic tongue and chemical analysis
    Analytica Chimica Acta, 2009
    Co-Authors: Alisa Rudnitskaya, Leigh Schmidtke, Ivonne Delgadillo, Andrey Legin, Geoffrey R Scollary
    Abstract:

    The influence of micro-oxygenation (MOX) and maceration with Oak Chips treatments on wine was studied on wine samples from three vintages produced in the Yarra Valley, Australia. A full factorial design was employed where two factors (MOX and Oak Chips treatments) had two levels and one factor (vintage) had three levels. Three replicated treatments were run for each factor's setting. Wine samples were analysed using conventional laboratory methods with respect to the phenolic wine compounds and colour attributes since the phenolic fraction of wine is most affected by both MOX and Oak maceration treatments. The same wine samples were measured with an electronic tongue based on potentiometric chemical sensors. The significance of treatments and vintage effects on wine phenolic compounds was assessed using ANOVA and ANOVA-Simultaneous Component Analysis (ASCA). Cross-validation was used for the ASCA sub-model optimisations and permutation test for evaluations of the significance of the factors. Main effects of vintage and maceration with Oak Chips were found to be significant for both physicochemical and the ET data. Main effect of MOX treatment was also found significant for the physicochemical parameters. The largest effect on the phenolic composition of wine was due to its vintage, which accounted for 70% and 33% of total variance in the physicochemical and ET data respectively. The ET was calibrated with respect to the total phenolic content, colour density and hue and chemical ages 1 and 2 and could predict these parameters of wine with good precision.

Alisa Rudnitskaya - One of the best experts on this subject based on the ideXlab platform.

  • measurements of the effects of wine maceration with Oak Chips using an electronic tongue
    Food Chemistry, 2017
    Co-Authors: Alisa Rudnitskaya, Leigh Schmidtke, Ana Reis, Rosario M M Domingues, Ivonne Delgadillo, Bruno Debus, Dmitry Kirsanov, Andrey Legin
    Abstract:

    Abstract The use of Oak products as a cheaper alternative to expensive wood barrels was recently permitted in Europe, which led to a continuous increase in the use of Oak Chips and staves in winemaking. The feasibility of the potentiometric electronic tongue as a tool for monitoring the effects of wine maceration with Oak Chips was evaluated. Four types of commercially available Oak Chips subjected to different thermal treatments and washing procedures and their mixture were studied. Ethanolic extracts of the Chips were analysed using electrospray mass spectrometry and 28 phenolic and furanic compounds were identified. The electronic tongue comprising 22 potentiometric chemical sensors could distinguish artificial wine solutions and Cabernet Sauvignon wine macerated with different types of Oak Chips, quantify total and non-flavonoid phenolic content, as well as the concentrations of added Oak Chips. Using measurements at two pH levels, 3.2 and 6.5, improved the accuracy of quantification.

  • study of the influence of micro oxygenation and Oak chip maceration on wine composition using an electronic tongue and chemical analysis
    Analytica Chimica Acta, 2009
    Co-Authors: Alisa Rudnitskaya, Leigh Schmidtke, Ivonne Delgadillo, Andrey Legin, Geoffrey R Scollary
    Abstract:

    The influence of micro-oxygenation (MOX) and maceration with Oak Chips treatments on wine was studied on wine samples from three vintages produced in the Yarra Valley, Australia. A full factorial design was employed where two factors (MOX and Oak Chips treatments) had two levels and one factor (vintage) had three levels. Three replicated treatments were run for each factor's setting. Wine samples were analysed using conventional laboratory methods with respect to the phenolic wine compounds and colour attributes since the phenolic fraction of wine is most affected by both MOX and Oak maceration treatments. The same wine samples were measured with an electronic tongue based on potentiometric chemical sensors. The significance of treatments and vintage effects on wine phenolic compounds was assessed using ANOVA and ANOVA-Simultaneous Component Analysis (ASCA). Cross-validation was used for the ASCA sub-model optimisations and permutation test for evaluations of the significance of the factors. Main effects of vintage and maceration with Oak Chips were found to be significant for both physicochemical and the ET data. Main effect of MOX treatment was also found significant for the physicochemical parameters. The largest effect on the phenolic composition of wine was due to its vintage, which accounted for 70% and 33% of total variance in the physicochemical and ET data respectively. The ET was calibrated with respect to the total phenolic content, colour density and hue and chemical ages 1 and 2 and could predict these parameters of wine with good precision.

Dimitris P Makris - One of the best experts on this subject based on the ideXlab platform.

  • Effect of the degree of toasting on the extraction pattern and profile of antioxidant polyphenols leached from Oak Chips in model wine systems
    European Food Research and Technology, 2015
    Co-Authors: Evelina Kanakaki, Danae Siderakou, Stamatina Kallithraka, Yorgos Kotseridis, Dimitris P Makris
    Abstract:

    The effect of the degree of toasting of Oak Chips used in wine ageing on the extraction pattern of polyphenols was investigated using model wine systems. Pattern identification was carried out employing a Box–Behnken experimental design and response surface methodology, using resident time (t) and amount of Chips (AChip) as the independent variables. The responses selected to assess the process were the total polyphenol concentration, the antiradical activity and the reducing power of the model wines. Further, a deeper insight into the effects exerted by chip toasting was provided by the examination of the analytical polyphenolic composition of model wines, using liquid chromatography–mass spectrometry. The results obtained demonstrated that even moderate toasting provoked drastic decrease in the native Oak wood polyphenols (ellagitannins), as indicated by the Folin–Ciocalteu assay, with a concomitant reduction in both the antiradical activity and reducing power. The evolution pattern for all three independent variables during model wine treatment with Chips having different degree of toasting was also substantially affected. Light toasting was shown to generate a series of small molecular weight phenolics, but some of them did not survive more intense (heavy) toasting.

  • extraction of phenolics in liquid model matrices containing Oak Chips kinetics liquid chromatography mass spectroscopy characterisation and association with in vitro antiradical activity
    Food Chemistry, 2008
    Co-Authors: Evangelia Karvela, Dimitris P Makris, Panagiotis Kefalas, Michael Moutounet
    Abstract:

    Four different liquid model matrices were utilised to study the leaching of polyphenols from Oak Chips. The matrices included distilled water, 12% (v/v) ethanol, 12% (v/v) ethanol adjusted to pH 3.4, and 55% (v/v) ethanol. Extraction of phenolics into the liquid systems was monitored by the estimation of the total polyphenol concentration, using the Folin-Ciocalteu method. The in vitro antiradical activity was also recorded using the stable DPPH radical, to ascertain enrichment of the solutions with potentially antioxidant compounds. As a final step, the polyphenolic composition of each matrix was characterised by means of liquid chromatography-electrospray ionisation mass spectrometry. The kinetics of polyphenol leaching into the liquid phase was found to obey a 2nd parameter power equation of the type y=ax(b), which produced a good fit of the data (p<0.0001). Kinetics was faster in distilled water up to a point, where after polyphenol extraction occurred at higher rate in the 55% ethanolic solution. The antiradical activity in all cases was highly correlated with total polyphenol concentration (p<0.001), providing that the amount of polyphenols extracted into the liquid media exerted a proportional antioxidant effect. The analytical examination by liquid chromatography-mass spectrometry revealed that the compounds implicated are hydrolysable tannins and hydrolysis products thereof.

  • Extraction of phenolics in liquid model matrices containing Oak Chips: Kinetics, liquid chromatography–mass spectroscopy characterisation and association with in vitro antiradical activity
    Food Chemistry, 2008
    Co-Authors: Evangelia Karvela, Dimitris P Makris, Panagiotis Kefalas, Michael Moutounet
    Abstract:

    Four different liquid model matrices were utilised to study the leaching of polyphenols from Oak Chips. The matrices included distilled water, 12% (v/v) ethanol, 12% (v/v) ethanol adjusted to pH 3.4, and 55% (v/v) ethanol. Extraction of phenolics into the liquid systems was monitored by the estimation of the total polyphenol concentration, using the Folin-Ciocalteu method. The in vitro antiradical activity was also recorded using the stable DPPH radical, to ascertain enrichment of the solutions with potentially antioxidant compounds. As a final step, the polyphenolic composition of each matrix was characterised by means of liquid chromatography-electrospray ionisation mass spectrometry. The kinetics of polyphenol leaching into the liquid phase was found to obey a 2nd parameter power equation of the type y=ax(b), which produced a good fit of the data (p

  • Extraction of phenolics in liquid model matrices containing Oak Chips: kinetics, liquid chromatography–mass spectroscopy characterisation and association with in vitro antiradical activity
    Food Chemistry, 2008
    Co-Authors: Evangelia Karvela, Dimitris P Makris, Panagiotis Kefalas, Michael Moutounet
    Abstract:

    Four different liquid model matrices were utilised to study the leaching of polyphenols from Oak Chips. The matrices included distilled water, 12%, (v/v) ethanol, 12% (v/v) ethanol adjusted to pH 3.4, and 55% (v/v) ethanol. Extraction of phenolics into the liquid systems was monitored by the estimation of the total polyphenol concentration, using the Folin-Ciocalteu method. The in vitro antiradical activity was also recorded using the stable DPPH- radical, to ascertain enrichment of the solutions with potentially antioxidant compounds. As a final step, the polyphenolic composition of each matrix was characterised by means of liquid chromatography-clectrospray ionisation mass spectrometry. The kinetics of polyphenol leaching into the liquid phase was found to obey a 2nd parameter power equation of the type y = ax(b), which produced a good fit of the data (p < 0.0001). Kinetics was faster in distilled water up to a point, where after polyplienol extraction occurred at higher rate in the 55% ethanolic solution. The antiradical activity in all cases was highly correlated with total polyphenol concentration (p < 0.001), providing that the amount of polyphenols extracted into the liquid media exerted a proportional antioxidant effect. The analytical examination by liquid chromatography-mass spectrometry revealed that the compounds implicated are hydrolysable tannins and hydrolysis products thereof