Pub Date : 2016-07-27DOI: 10.20870/OENO-ONE.2016.50.2.784
J. Taylor, L. Sanchez, B. Sams, Luke Haggerty, Rhiann Jakubowski, S. Djafour, T. Bates
Aims: Yield monitors are becoming more common in North America. This research evaluates the precision and accuracy of a retro-fitted, commercially available grape yield monitor mid-season, for crop estimation and crop thinning applications, and at harvest for yield mapping.Methods and Results: Several grape yield monitors were mounted on the discharge conveyor belt of grape harvesters in both commercial and research vineyards in North America. Sensor response was compared to manual measurements at multiple masses, ranging from 20 kg to 28 Mg over the course of three seasons. Measurements were taken during crop thinning and estimation (mid-season) and at harvest. Results showed that the grape yield monitor performance was sufficient to generate good spatial maps of the relative variation in harvest yield and mid-season thinned yield. However, at harvest the sensor showed a shift in response between days of up to ±15%, such that the generation of absolute yield maps required a daily calibration against a known mass. Within a day (single harvest operation) the sensor response did not appear to drift. Mid-season applications required a different calibration to harvest applications.Conclusion: The yield sensor worked well for both mid-season and at harvest operations in North American vineyards but required a daily calibration to avoid drift issues. The mid-season yield calibrations were different between seasons; however, the harvest calibration factor was stable between seasons.Significance and Impact of study: The study showed that a commercial yield monitor with correct calibration was effective at even low fruit flow. This opens the possibility of using a harvest sensor mid-season to mechanically estimate fruit load from small point samples and to map the amount of fruit removed during fruit thinning operations. This will improve the quality of information available to viticulturist to understand fruit and crop load. The commercial yield monitor is suitable for use in North American vineyards.
{"title":"Evaluation of a commercial grape yield monitor for use mid-season and at-harvest","authors":"J. Taylor, L. Sanchez, B. Sams, Luke Haggerty, Rhiann Jakubowski, S. Djafour, T. Bates","doi":"10.20870/OENO-ONE.2016.50.2.784","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2016.50.2.784","url":null,"abstract":"Aims: Yield monitors are becoming more common in North America. This research evaluates the precision and accuracy of a retro-fitted, commercially available grape yield monitor mid-season, for crop estimation and crop thinning applications, and at harvest for yield mapping.Methods and Results: Several grape yield monitors were mounted on the discharge conveyor belt of grape harvesters in both commercial and research vineyards in North America. Sensor response was compared to manual measurements at multiple masses, ranging from 20 kg to 28 Mg over the course of three seasons. Measurements were taken during crop thinning and estimation (mid-season) and at harvest. Results showed that the grape yield monitor performance was sufficient to generate good spatial maps of the relative variation in harvest yield and mid-season thinned yield. However, at harvest the sensor showed a shift in response between days of up to ±15%, such that the generation of absolute yield maps required a daily calibration against a known mass. Within a day (single harvest operation) the sensor response did not appear to drift. Mid-season applications required a different calibration to harvest applications.Conclusion: The yield sensor worked well for both mid-season and at harvest operations in North American vineyards but required a daily calibration to avoid drift issues. The mid-season yield calibrations were different between seasons; however, the harvest calibration factor was stable between seasons.Significance and Impact of study: The study showed that a commercial yield monitor with correct calibration was effective at even low fruit flow. This opens the possibility of using a harvest sensor mid-season to mechanically estimate fruit load from small point samples and to map the amount of fruit removed during fruit thinning operations. This will improve the quality of information available to viticulturist to understand fruit and crop load. The commercial yield monitor is suitable for use in North American vineyards.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"50 1","pages":"57-63"},"PeriodicalIF":0.0,"publicationDate":"2016-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67758221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-30DOI: 10.20870/OENO-ONE.2015.49.2.86
Gustavo A. Lobos, C. Acevedo-Opazo, Alejandro Guajardo-Moreno, H. Valdés-Gómez, J. Taylor, V. F. Laurie
Aims: Long exposure to high temperatures or UV-radiation may induce negative effects on vine physiology and grape composition. Here, the effects of two methods to moderate radiation and temperature in the fruit zone of a Cabernet Sauvignon vineyard were evaluated against a control.Methods and results: The treatments assessed were: (a) periodical spraying of kaolin on leaves and bunches and (b) fruit zone netting with a Raschell’s type mesh. The kaolin-based treatment increased the reflectance of light and moderately reduced fruit temperature (~1oC below the control), whilst the shading net caused a significant reduction in radiation and temperature in the fruit zone (~7oC below the control). The Net treatment showed lower (more negative) stem water potential values than the control, but did not persist until the end of the trial. Also, none of the treatments led to significant changes in stomatal conductance, transpiration or CO2 assimilation throughout the season. However, the incidence and severity of fruit dehydration was significantly lower in the treated plants compared to the control. Finally, no differences in fruit chemical composition were observed between the treatments and the control.Conclusion: Under the conditions of this trial, both treatments tested were sufficient in moderating the negative effects of excess radiation or high temperature on grape berries.Significance and impact of the study: Kaolin-based particle spraying and fruit zone netting were proved to be feasible practical alternatives to lessen the negative effects of excess radiation or high temperature on grape berries, under hot climate.
{"title":"Effects of kaolin-based particle film and fruit zone netting on Cabernet Sauvignon grapevine physiology and fruit quality","authors":"Gustavo A. Lobos, C. Acevedo-Opazo, Alejandro Guajardo-Moreno, H. Valdés-Gómez, J. Taylor, V. F. Laurie","doi":"10.20870/OENO-ONE.2015.49.2.86","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2015.49.2.86","url":null,"abstract":"Aims: Long exposure to high temperatures or UV-radiation may induce negative effects on vine physiology and grape composition. Here, the effects of two methods to moderate radiation and temperature in the fruit zone of a Cabernet Sauvignon vineyard were evaluated against a control.Methods and results: The treatments assessed were: (a) periodical spraying of kaolin on leaves and bunches and (b) fruit zone netting with a Raschell’s type mesh. The kaolin-based treatment increased the reflectance of light and moderately reduced fruit temperature (~1oC below the control), whilst the shading net caused a significant reduction in radiation and temperature in the fruit zone (~7oC below the control). The Net treatment showed lower (more negative) stem water potential values than the control, but did not persist until the end of the trial. Also, none of the treatments led to significant changes in stomatal conductance, transpiration or CO2 assimilation throughout the season. However, the incidence and severity of fruit dehydration was significantly lower in the treated plants compared to the control. Finally, no differences in fruit chemical composition were observed between the treatments and the control.Conclusion: Under the conditions of this trial, both treatments tested were sufficient in moderating the negative effects of excess radiation or high temperature on grape berries.Significance and impact of the study: Kaolin-based particle spraying and fruit zone netting were proved to be feasible practical alternatives to lessen the negative effects of excess radiation or high temperature on grape berries, under hot climate.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"26 1","pages":"137-144"},"PeriodicalIF":0.0,"publicationDate":"2015-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67757659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.20870/OENO-ONE.2012.46.4.1530
G. Zdunić, I. Budić-Leto, U. Vrhovsek, Iva Tomić-Potrebuješ, E. Maletić
A four-year study (2007 through 2010) was carried out to determine agronomic, biological, and oenological characteristics of Dobricic grapevines so as to evaluate this cultivar and protect it from extinction. 38 characteristics from the OIV descriptor list were used to describe young shoot, mature leaf, cluster, and berry morphology of Dobricic grapevines. The dimensions of an average leaf were constructed from measured leaf variables. A typical Dobricic genotype at nine microsatellite loci is presented. ELISA analysis revealed high virus incidence and all samples tested were GLRaV-3 positive. The profile of different classes of polyphenols in Dobricic wine was determined using HPLC and spectrophotometry. The concentrations of polyphenols in Dobricic wine, especially anthocyanins, hydroxycinnamic acids and stilbenes, were high compared to major red wines reported in the literature. Descriptive sensory analysis was carried out to determine the aroma attributes describing a Dobricic monovarietal wine. Knowledge of the biodiversity of the grapevine cultivars of Croatia is still scant. This study provides for the first time ampelographic and oenological information on Dobricic grapevines and demonstrates its high quality potential. Significance and impact of the study: The results of the ampelographic characterization would be helpful in the identification and selection of Dobricic for cultivation in certain vine-growing areas. The outstanding quality of Dobricic makes it very promising for wine blending (colour improvement) and plant breeding purposes.
{"title":"Ampelographic and oenological characterization of the ancient grapevine cv. Dobricic grown in the coastal region of Croatia","authors":"G. Zdunić, I. Budić-Leto, U. Vrhovsek, Iva Tomić-Potrebuješ, E. Maletić","doi":"10.20870/OENO-ONE.2012.46.4.1530","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2012.46.4.1530","url":null,"abstract":"A four-year study (2007 through 2010) was carried out to determine agronomic, biological, and oenological characteristics of Dobricic grapevines so as to evaluate this cultivar and protect it from extinction. 38 characteristics from the OIV descriptor list were used to describe young shoot, mature leaf, cluster, and berry morphology of Dobricic grapevines. The dimensions of an average leaf were constructed from measured leaf variables. A typical Dobricic genotype at nine microsatellite loci is presented. ELISA analysis revealed high virus incidence and all samples tested were GLRaV-3 positive. The profile of different classes of polyphenols in Dobricic wine was determined using HPLC and spectrophotometry. The concentrations of polyphenols in Dobricic wine, especially anthocyanins, hydroxycinnamic acids and stilbenes, were high compared to major red wines reported in the literature. Descriptive sensory analysis was carried out to determine the aroma attributes describing a Dobricic monovarietal wine. Knowledge of the biodiversity of the grapevine cultivars of Croatia is still scant. This study provides for the first time ampelographic and oenological information on Dobricic grapevines and demonstrates its high quality potential. Significance and impact of the study: The results of the ampelographic characterization would be helpful in the identification and selection of Dobricic for cultivation in certain vine-growing areas. The outstanding quality of Dobricic makes it very promising for wine blending (colour improvement) and plant breeding purposes.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"46 1","pages":"263-273"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67756398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-09-30DOI: 10.20870/OENO-ONE.2012.46.3.1515
Jonathan D. Anderson, Gregory V. Jones, A. Tait, A. Hall, M. Trought
Aims: This research analyzes four climate indices derived from gridded, interpolated data to assess New Zealand’s climate structure and variation among wine regions.Methods and results: High resolution gridded data based on 1971-2000 climate normals was used to characterize climate indices depicting viticultural suitability in a geographic information system. The statistical properties of each index were assessed over 21 New Zealand viticulture regions. The results show predominately cool to moderately warm climate suitability in New Zealand, comparable to many European and United States regions. While many viticulture regions have one primary class of suitability, variability of climate within regions can be significant, with some regions containing two to four climate classes, making them suitable for a greater range of cultivars.Conclusion: While the indices depict broad patterns expected over New Zealand, both within and between region variations can be substantial among the indices. However, two indices, Growing Season Average Temperature (GST) and Growing Degree-Days (GDD), are functionally identical, but GST is easier to calculate and overcomes many methodological issues in GDD.Significance and impact of the study: This research provides the basis for evaluating general suitability for viticulture in New Zealand, assists comparisons between viticulture regions in New Zealand and worldwide, and offers growers measures of assessing appropriate cultivars and sites.
{"title":"Analysis of viticulture region climate structure and suitability in New Zealand","authors":"Jonathan D. Anderson, Gregory V. Jones, A. Tait, A. Hall, M. Trought","doi":"10.20870/OENO-ONE.2012.46.3.1515","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2012.46.3.1515","url":null,"abstract":"Aims: This research analyzes four climate indices derived from gridded, interpolated data to assess New Zealand’s climate structure and variation among wine regions.Methods and results: High resolution gridded data based on 1971-2000 climate normals was used to characterize climate indices depicting viticultural suitability in a geographic information system. The statistical properties of each index were assessed over 21 New Zealand viticulture regions. The results show predominately cool to moderately warm climate suitability in New Zealand, comparable to many European and United States regions. While many viticulture regions have one primary class of suitability, variability of climate within regions can be significant, with some regions containing two to four climate classes, making them suitable for a greater range of cultivars.Conclusion: While the indices depict broad patterns expected over New Zealand, both within and between region variations can be substantial among the indices. However, two indices, Growing Season Average Temperature (GST) and Growing Degree-Days (GDD), are functionally identical, but GST is easier to calculate and overcomes many methodological issues in GDD.Significance and impact of the study: This research provides the basis for evaluating general suitability for viticulture in New Zealand, assists comparisons between viticulture regions in New Zealand and worldwide, and offers growers measures of assessing appropriate cultivars and sites.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"46 1","pages":"149-165"},"PeriodicalIF":0.0,"publicationDate":"2012-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67755626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-06-30DOI: 10.20870/OENO-ONE.2011.45.2.1486
R. V. Mota, A. Favero, C. P. C. Silva, E. Purgatto, Tânia M. Shiga, M. A. D. Regina
Aims: Geographical indication plays an important role in the improvement of wine quality. In this context, the search for new grape growing areas has been constant. The Sao Francisco River Valley in the cerrado of Minas Gerais State (Brazil) has been pointed out in the Geoviticulture Multicriteria Climatic Classification System (MCC System) as a potentially winegrowing region, especially considering the autumn-winter period when night temperatures are favorable to grape ripening. In this work, we studied the maturation curves and fruit composition of four wine grape varieties (Syrah, Merlot, Cabernet-Sauvignon and Cabernet Franc) in two growing seasons in order to validate the state of Minas Gerais as a new winegrowing region in Brazil.Methods and results: Quality parameters (berry weight, pH, titratable acidity and total soluble solids) were measured weekly from veraison to harvest, and sugar, organic acid, anthocyanin and phenolic concentrations were determined in must and berry skins and seeds at harvest. Syrah berries showed the highest weight throughout maturation which contributed to higher yield (8.92 ton ha-1), followed closely by Merlot (8.07 ton ha-1). Berry sugar concentrations were higher and malic acid levels were lower than the values usually observed in wine grapes harvested during summer in traditional winegrowing regions in Brazil. Cabernet Franc showed lower levels of anthocyanins and skin phenolics per kg berries and the highest values of seed phenolics, which were not affected by growing season.Conclusion: Weather conditions of the cerrado of Minas Gerais State in Brazil during winter allowed complete maturation of Cabernet-Sauvignon, Cabernet Franc, Merlot and Syrah cultivars as revealed by the satisfactory sugar, anthocyanin and skin phenolic accumulation.Significance and impact of the study: This study revealed the potential of the cerrado ecoregion in the northeast of Minas Gerais to become a new winemaking region in Brazil.
{"title":"Wine grape quality of grapevines grown in the cerrado ecoregion of Brazil","authors":"R. V. Mota, A. Favero, C. P. C. Silva, E. Purgatto, Tânia M. Shiga, M. A. D. Regina","doi":"10.20870/OENO-ONE.2011.45.2.1486","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2011.45.2.1486","url":null,"abstract":"Aims: Geographical indication plays an important role in the improvement of wine quality. In this context, the search for new grape growing areas has been constant. The Sao Francisco River Valley in the cerrado of Minas Gerais State (Brazil) has been pointed out in the Geoviticulture Multicriteria Climatic Classification System (MCC System) as a potentially winegrowing region, especially considering the autumn-winter period when night temperatures are favorable to grape ripening. In this work, we studied the maturation curves and fruit composition of four wine grape varieties (Syrah, Merlot, Cabernet-Sauvignon and Cabernet Franc) in two growing seasons in order to validate the state of Minas Gerais as a new winegrowing region in Brazil.Methods and results: Quality parameters (berry weight, pH, titratable acidity and total soluble solids) were measured weekly from veraison to harvest, and sugar, organic acid, anthocyanin and phenolic concentrations were determined in must and berry skins and seeds at harvest. Syrah berries showed the highest weight throughout maturation which contributed to higher yield (8.92 ton ha-1), followed closely by Merlot (8.07 ton ha-1). Berry sugar concentrations were higher and malic acid levels were lower than the values usually observed in wine grapes harvested during summer in traditional winegrowing regions in Brazil. Cabernet Franc showed lower levels of anthocyanins and skin phenolics per kg berries and the highest values of seed phenolics, which were not affected by growing season.Conclusion: Weather conditions of the cerrado of Minas Gerais State in Brazil during winter allowed complete maturation of Cabernet-Sauvignon, Cabernet Franc, Merlot and Syrah cultivars as revealed by the satisfactory sugar, anthocyanin and skin phenolic accumulation.Significance and impact of the study: This study revealed the potential of the cerrado ecoregion in the northeast of Minas Gerais to become a new winemaking region in Brazil.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"45 1","pages":"101-109"},"PeriodicalIF":0.0,"publicationDate":"2011-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67754943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-31DOI: 10.20870/OENO-ONE.2010.44.4.1475
D. González-Ramos, A. Muñoz, A. Ortiz‐Julien, A. Palacios, J. Heras, R. Gonzalez
Methods and results: UV mutagenesis was used for genetic improvement of the industrial wine yeast strain ADY1. Cell wall-related phenotypes were used as primary selection criteria; an additional screening procedure was developed based on the detection of the released mannoproteins by hybridization with peroxidase-labeled Concanavalin A. Mannoprotein overproduction was assessed in laboratory media as well as in grapevine juice. One mutant strain, renamed HPS, was selected using these criteria. HPS showed increased mannoprotein release in different culture media, including natural must. Moreover, white wines fermented with this improved strain were less susceptible to protein haze than equivalent wines fermented with the original ADY1 strain. Red wines fermented with the mutant strain were also polysaccharide-enriched as compared to the original one. Conclusion : No clear correlation between a specific cell wall-related phenotype, or a combination of them, and improved release of polysaccharides by yeast random mutants could be established, and not all strains identified by in vitro assays as mannoprotein overproducing mutants were found positive for mannoprotein release in industrial conditions. Nevertheless, UV mutagenesis, combined with Concanavalin A detection, seems to be a viable way to improve mannoprotein release by industrial wine yeast strains. Significance and impact of the study: This study is one of the few recent reports on genetic improvement of wine yeast strains by non-recombinant genetic tools. It shows that mannoprotein release can be genetically improved and, for the first time, describes a successful selection procedure for such a complex character. These strains are potentially useful for the improvement of mannoprotein-related characters of white and red wines.
{"title":"A SACCHAROMYCES CEREVISIAE WINE YEAST STRAIN OVERPRODUCING MANNOPROTEINS SELECTED THROUGH CLASSICAL GENETIC METHODS","authors":"D. González-Ramos, A. Muñoz, A. Ortiz‐Julien, A. Palacios, J. Heras, R. Gonzalez","doi":"10.20870/OENO-ONE.2010.44.4.1475","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2010.44.4.1475","url":null,"abstract":"Methods and results: UV mutagenesis was used for genetic improvement of the industrial wine yeast strain ADY1. Cell wall-related phenotypes were used as primary selection criteria; an additional screening procedure was developed based on the detection of the released mannoproteins by hybridization with peroxidase-labeled Concanavalin A. Mannoprotein overproduction was assessed in laboratory media as well as in grapevine juice. One mutant strain, renamed HPS, was selected using these criteria. HPS showed increased mannoprotein release in different culture media, including natural must. Moreover, white wines fermented with this improved strain were less susceptible to protein haze than equivalent wines fermented with the original ADY1 strain. Red wines fermented with the mutant strain were also polysaccharide-enriched as compared to the original one. Conclusion : No clear correlation between a specific cell wall-related phenotype, or a combination of them, and improved release of polysaccharides by yeast random mutants could be established, and not all strains identified by in vitro assays as mannoprotein overproducing mutants were found positive for mannoprotein release in industrial conditions. Nevertheless, UV mutagenesis, combined with Concanavalin A detection, seems to be a viable way to improve mannoprotein release by industrial wine yeast strains. Significance and impact of the study: This study is one of the few recent reports on genetic improvement of wine yeast strains by non-recombinant genetic tools. It shows that mannoprotein release can be genetically improved and, for the first time, describes a successful selection procedure for such a complex character. These strains are potentially useful for the improvement of mannoprotein-related characters of white and red wines.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"44 1","pages":"243-249"},"PeriodicalIF":0.0,"publicationDate":"2010-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67755046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-31DOI: 10.20870/OENO-ONE.2010.44.4.1477
D. Picque, P. Lieben, P. Chrétien, J. Béguin, Laurence Guerin
Aim: The objective of the present study was to assess the ripening of grapes collected at different stages of maturation between the “veraison” and harvest periods from mid-infrared spectroscopy (MIRS) analysis.Methods and results: Grape berries of Cabernet Franc collected in two locations of the Loire Valley region (Touraine and Anjou), from 28 vine plots and during two vintages (2005 and 2006) were analysed. With principal component analysis (PCA) of spectral data of grape musts, different levels of ripening were described during the three to four weeks before harvest. A separation according to origin (Touraine or Anjou) was also observed and confirmed by the results of partial least squares (PLS) discriminant analysis (88 % of correct classification). Similar evolutions and geographical discriminations were obtained for specific physicochemical parameters. By PLS regression, good predictions of titratable acidity and sugar concentration from berry spectral data were obtained, with root mean square error of prediction (RMSEP) of 0.53 g/L for titratable acidity (expressed in H2SO4) and 8 g/L for sugar concentration. Moreover, when the data from only one of the regions were considered, the predictions of titratable acidity and sugar concentration were improved and those of real acidity (pH) and maturity index were then satisfactory. The RMSEP values for samples from Touraine and Anjou were reduced, respectively, to 0.05 and 0.02 units for pH, 0.4 and 0.12 g/L for titratable acidity (expressed in H2SO4), 6.6 and 3.2 g/L for sugar concentration, and 5 and 2.2 units for maturity index.Conclusion: Spectroscopic and classic chemical analyses of grape berries yielded highly similar results. The evolution of berries from “veraison” to harvest can be characterized according to both time course and region. The samples showed similar PCA results for chemical and IR spectra parameters. PLS regression between chemical and spectral data showed that Fourier transform IR is a good method to predict acidity and sugar concentration throughout ripening. And the results for these parameters, as well as for pH, maturity index and anthocyanin concentration, are improved if the regressions are calculated from sample sets restricted to a single growing region. Consequently, a calibration model is required for each grape geographical origin.Significance and impact of the study: The potential of MIRS was demonstrated for the quantification of the main indicators of maturity during berry ripening. Furthermore, these spectra can be used to estimate grape maturity in particular in reference to a spectral database established over several years of study. The association infrared spectroscopy, chemometric methods and database will help to monitor ripening and to determine the optimum harvest date.
{"title":"Assessment of maturity of Loire Valley wine grapes by mid-infrared spectroscopy","authors":"D. Picque, P. Lieben, P. Chrétien, J. Béguin, Laurence Guerin","doi":"10.20870/OENO-ONE.2010.44.4.1477","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2010.44.4.1477","url":null,"abstract":"Aim: The objective of the present study was to assess the ripening of grapes collected at different stages of maturation between the “veraison” and harvest periods from mid-infrared spectroscopy (MIRS) analysis.Methods and results: Grape berries of Cabernet Franc collected in two locations of the Loire Valley region (Touraine and Anjou), from 28 vine plots and during two vintages (2005 and 2006) were analysed. With principal component analysis (PCA) of spectral data of grape musts, different levels of ripening were described during the three to four weeks before harvest. A separation according to origin (Touraine or Anjou) was also observed and confirmed by the results of partial least squares (PLS) discriminant analysis (88 % of correct classification). Similar evolutions and geographical discriminations were obtained for specific physicochemical parameters. By PLS regression, good predictions of titratable acidity and sugar concentration from berry spectral data were obtained, with root mean square error of prediction (RMSEP) of 0.53 g/L for titratable acidity (expressed in H2SO4) and 8 g/L for sugar concentration. Moreover, when the data from only one of the regions were considered, the predictions of titratable acidity and sugar concentration were improved and those of real acidity (pH) and maturity index were then satisfactory. The RMSEP values for samples from Touraine and Anjou were reduced, respectively, to 0.05 and 0.02 units for pH, 0.4 and 0.12 g/L for titratable acidity (expressed in H2SO4), 6.6 and 3.2 g/L for sugar concentration, and 5 and 2.2 units for maturity index.Conclusion: Spectroscopic and classic chemical analyses of grape berries yielded highly similar results. The evolution of berries from “veraison” to harvest can be characterized according to both time course and region. The samples showed similar PCA results for chemical and IR spectra parameters. PLS regression between chemical and spectral data showed that Fourier transform IR is a good method to predict acidity and sugar concentration throughout ripening. And the results for these parameters, as well as for pH, maturity index and anthocyanin concentration, are improved if the regressions are calculated from sample sets restricted to a single growing region. Consequently, a calibration model is required for each grape geographical origin.Significance and impact of the study: The potential of MIRS was demonstrated for the quantification of the main indicators of maturity during berry ripening. Furthermore, these spectra can be used to estimate grape maturity in particular in reference to a spectral database established over several years of study. The association infrared spectroscopy, chemometric methods and database will help to monitor ripening and to determine the optimum harvest date.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"44 1","pages":"219-229"},"PeriodicalIF":0.0,"publicationDate":"2010-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67755098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-09-30DOI: 10.20870/OENO-ONE.2010.44.3.1468
M. Squadrito, O. Corona, G. Ansaldi, R. Stefano
Aims: This study aimed at acquiring knowledge of the evolution of anthocyanins from grape to wine and the possibility of deducing the varietal origin of a wine from its anthocyanin profile.Methods and results: The anthocyanin « fingerprint », or profile, of a series of autochthonous Sicilian accessions and their respective young wines was determined by HPLC-DAD in 2008. Data were evaluated by taking into account the evolution of the percentages of side-ring di-oxygenated and tri-oxygenated anthocyanins, the ratio between acetylated and p-coumaroylated derivatives, and the principal component analysis (PCA) results. From grape to the end of alcoholic fermentation, the percentages of 3-glucosides of cyanidin, peonidin, delphinidin and p-coumaroylglucosides decreased, whereas those of malvidin-3-glucoside, acetylated derivatives and, in some cases, petunidin-3-glucoside increased. In many but not all wines, after malolactic fermentation, the percentages of p-coumaroylated derivatives decreased further and those of cyanidin-3-glucoside and acetylated derivatives increased ; less variation was observed in malvidin-3-glucoside values.Conclusions: From grapes to young wines, the anthocyanin profiles varied mainly because of the activity of polyphenol oxidase (PPO), yeasts and lactic acid bacteria. However, they were substantially retained in wines from varieties in which tri-oxygenated side-ring anthocyanins prevailed, but were dramatically different from the respective grapes in wines from varieties rich in di-oxygenated anthocyanins, or in which the di-oxygenated forms prevailed over the tri-oxygenated ones. PCA analysis confirmed these findings.Significance and impact of the study: Only in varieties in which the anthocyanin profile of grapes is characterized by low percentages of di-oxygenated side-ring forms is it possible to gain information about the varietal origin of a young wine by comparing the profiles of both grape and wine. However, great care is required.
{"title":"Evolution of anthocyanin profile from grape to wine.","authors":"M. Squadrito, O. Corona, G. Ansaldi, R. Stefano","doi":"10.20870/OENO-ONE.2010.44.3.1468","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2010.44.3.1468","url":null,"abstract":"Aims: This study aimed at acquiring knowledge of the evolution of anthocyanins from grape to wine and the possibility of deducing the varietal origin of a wine from its anthocyanin profile.Methods and results: The anthocyanin « fingerprint », or profile, of a series of autochthonous Sicilian accessions and their respective young wines was determined by HPLC-DAD in 2008. Data were evaluated by taking into account the evolution of the percentages of side-ring di-oxygenated and tri-oxygenated anthocyanins, the ratio between acetylated and p-coumaroylated derivatives, and the principal component analysis (PCA) results. From grape to the end of alcoholic fermentation, the percentages of 3-glucosides of cyanidin, peonidin, delphinidin and p-coumaroylglucosides decreased, whereas those of malvidin-3-glucoside, acetylated derivatives and, in some cases, petunidin-3-glucoside increased. In many but not all wines, after malolactic fermentation, the percentages of p-coumaroylated derivatives decreased further and those of cyanidin-3-glucoside and acetylated derivatives increased ; less variation was observed in malvidin-3-glucoside values.Conclusions: From grapes to young wines, the anthocyanin profiles varied mainly because of the activity of polyphenol oxidase (PPO), yeasts and lactic acid bacteria. However, they were substantially retained in wines from varieties in which tri-oxygenated side-ring anthocyanins prevailed, but were dramatically different from the respective grapes in wines from varieties rich in di-oxygenated anthocyanins, or in which the di-oxygenated forms prevailed over the tri-oxygenated ones. PCA analysis confirmed these findings.Significance and impact of the study: Only in varieties in which the anthocyanin profile of grapes is characterized by low percentages of di-oxygenated side-ring forms is it possible to gain information about the varietal origin of a young wine by comparing the profiles of both grape and wine. However, great care is required.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"44 1","pages":"167-177"},"PeriodicalIF":0.0,"publicationDate":"2010-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67755325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-30DOI: 10.20870/OENO-ONE.2010.44.2.1461
G. Arfelli, E. Sartini, F. Bordini, C. Caprara, F. Pezzi
Aims: The aim of this work was to verify the influence of mechanical harvesting and postharvest treatments on wine composition.Methods and results: Trials were carried out in triplicate on cv. Montuni grapes. The estimated best setting frequency for the mechanical harvester was 410 shakes/min. Comparing hand-picked and mechanically harvested grapes, the reduced extract and pH results were lower for the hand-picked grapes, showing a more evident berry breakage caused by the mechanical harvester. The wines obtained from mechanically harvested grapes had a lower phenolic compound content than wines produced with hand-picked grapes, indicating that oxidation phenomena occurred; the trend for postharvest treated grapes was different. The significantly lower amount of higher alcohols in the hand-picked grapes trial than in the mechanically harvested ones could be explained by a lower amount of their precursors and oxygen in musts. The sensory differences among the trials were significant for some parameters, but an overall view of the data suggested that the differences were not remarkable and all the wines were good.Conclusion: Postharvest treatments reduce the loss of natural antioxidant compounds found in wines produced from mechanically harvested grapes. Mechanical harvesting does not have a negative influence on wine composition if matched with the proper vineyard characteristics, machine settings and postharvest treatments. The typicality of Montuni wine is maintained in the cases of grapes harvested mechanically with, but also without, any postharvest treatment. The use of these treatments is otherwise useful to obtain wines with a better stability.Significance and impact of the study: With respect to mechanical harvesting, this study highlights the importance of maintaining and/or improving the quality of mechanically harvested grapes containing the harvesting costs.
{"title":"Mechanical harvesting optimization and postharvest treatments to improve wine quality.","authors":"G. Arfelli, E. Sartini, F. Bordini, C. Caprara, F. Pezzi","doi":"10.20870/OENO-ONE.2010.44.2.1461","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2010.44.2.1461","url":null,"abstract":"Aims: The aim of this work was to verify the influence of mechanical harvesting and postharvest treatments on wine composition.Methods and results: Trials were carried out in triplicate on cv. Montuni grapes. The estimated best setting frequency for the mechanical harvester was 410 shakes/min. Comparing hand-picked and mechanically harvested grapes, the reduced extract and pH results were lower for the hand-picked grapes, showing a more evident berry breakage caused by the mechanical harvester. The wines obtained from mechanically harvested grapes had a lower phenolic compound content than wines produced with hand-picked grapes, indicating that oxidation phenomena occurred; the trend for postharvest treated grapes was different. The significantly lower amount of higher alcohols in the hand-picked grapes trial than in the mechanically harvested ones could be explained by a lower amount of their precursors and oxygen in musts. The sensory differences among the trials were significant for some parameters, but an overall view of the data suggested that the differences were not remarkable and all the wines were good.Conclusion: Postharvest treatments reduce the loss of natural antioxidant compounds found in wines produced from mechanically harvested grapes. Mechanical harvesting does not have a negative influence on wine composition if matched with the proper vineyard characteristics, machine settings and postharvest treatments. The typicality of Montuni wine is maintained in the cases of grapes harvested mechanically with, but also without, any postharvest treatment. The use of these treatments is otherwise useful to obtain wines with a better stability.Significance and impact of the study: With respect to mechanical harvesting, this study highlights the importance of maintaining and/or improving the quality of mechanically harvested grapes containing the harvesting costs.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"185 1","pages":"101-115"},"PeriodicalIF":0.0,"publicationDate":"2010-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67754792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-12-31DOI: 10.20870/OENO-ONE.2009.43.4.791
S. R. Segade, I. Orriols, V. Gerbi, L. Rolle
Aims : Phenolic compounds, extractable from grape skins and seeds, have a notable influence on the quality of red wines. Therefore, in this work the phenolic composition of 13 red grape cultivars, grown in one of the most traditional Spanish vine zones, was studied in order to identify significant varietal differences. Methods and results : Anthocyanin concentration and profile, total proanthocyanidin and flavanol contents in berry skins and seeds were determined by spectrophotometric and HPLC methods. The highest concentrations of total anthocyanins was found in the Loureira Tinta, Souson and Ferrol varieties, while Ferrol was rich in proanthocyanidins in berry skin and Caino Bravo was rich in proanthocyanidins and flavanols in berry seeds. Malvidin-3-monoglucoside was usually the major anthocyanin. Nevertheless, the anthocyanin profile was characterized mainly of di-substituted molecules for Albarello, Brancellao and Caino da Terra grapes. Ferrol, Loureira Tinta and Souson grapes showed the highest values of primitive anthocyanins (delphinidin and petunidin derivatives). Conclusion : Many differences in the phenolic composition of the cultivars studied were found. The results of the phenolic characterization can be utilized in winery in order to apply the most appropriate maceration and winemaking techniques to the processed grapes. Significance and impact of study : Knowledge of the biodiversity of the grape varieties of Galicia (North-West Spain) is still scarce. This study, on phenolic composition, provides oenological information that can be useful to improve the quality of the wines produced.
目的:从葡萄果皮和葡萄籽中提取的酚类化合物对红葡萄酒的品质有显著的影响。因此，在这项工作中，研究了生长在西班牙最传统的葡萄产区之一的13个红葡萄品种的酚类成分，以确定显著的品种差异。方法与结果:采用分光光度法和高效液相色谱法测定浆果果皮和种子中花青素的浓度和含量、总原花青素和黄烷醇的含量。总花青素含量最高的品种是Loureira Tinta、Souson和Ferrol，而Ferrol在浆果皮中富含原花青素，而Caino Bravo在浆果种子中富含原花青素和黄烷醇。malvidin -3-单葡萄糖苷通常是主要的花青素。然而，Albarello、Brancellao和Caino da Terra葡萄的花青素谱主要是双取代分子。Ferrol、Loureira Tinta和Souson葡萄的原始花青素(飞燕花青素和矮牵牛花青素衍生物)含量最高。结论:所研究品种的酚类成分存在较大差异。酚类表征的结果可用于酿酒厂，以便对加工过的葡萄采用最合适的浸渍和酿酒技术。研究的意义和影响:对加利西亚(西班牙西北部)葡萄品种生物多样性的了解仍然很少。这项关于酚类成分的研究，提供了有助于提高葡萄酒质量的酿酒学信息。
{"title":"Phenolic characterization of thirteen red grape cultivars from Galicia by anthocyanin profile and flavanol composition","authors":"S. R. Segade, I. Orriols, V. Gerbi, L. Rolle","doi":"10.20870/OENO-ONE.2009.43.4.791","DOIUrl":"https://doi.org/10.20870/OENO-ONE.2009.43.4.791","url":null,"abstract":"Aims : Phenolic compounds, extractable from grape skins and seeds, have a notable influence on the quality of red wines. Therefore, in this work the phenolic composition of 13 red grape cultivars, grown in one of the most traditional Spanish vine zones, was studied in order to identify significant varietal differences. Methods and results : Anthocyanin concentration and profile, total proanthocyanidin and flavanol contents in berry skins and seeds were determined by spectrophotometric and HPLC methods. The highest concentrations of total anthocyanins was found in the Loureira Tinta, Souson and Ferrol varieties, while Ferrol was rich in proanthocyanidins in berry skin and Caino Bravo was rich in proanthocyanidins and flavanols in berry seeds. Malvidin-3-monoglucoside was usually the major anthocyanin. Nevertheless, the anthocyanin profile was characterized mainly of di-substituted molecules for Albarello, Brancellao and Caino da Terra grapes. Ferrol, Loureira Tinta and Souson grapes showed the highest values of primitive anthocyanins (delphinidin and petunidin derivatives). Conclusion : Many differences in the phenolic composition of the cultivars studied were found. The results of the phenolic characterization can be utilized in winery in order to apply the most appropriate maceration and winemaking techniques to the processed grapes. Significance and impact of study : Knowledge of the biodiversity of the grape varieties of Galicia (North-West Spain) is still scarce. This study, on phenolic composition, provides oenological information that can be useful to improve the quality of the wines produced.","PeriodicalId":56279,"journal":{"name":"Journal International Des Sciences De La Vigne et Du Vin","volume":"24 1","pages":"189-198"},"PeriodicalIF":0.0,"publicationDate":"2009-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67754556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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