E. Hernández-Montes, Yun Zhang, B. Chang, N. Shcherbatyuk, M. Keller
Asynchronous development of grape berries leads to high variation among berry samples collected during veraison. We applied a stratified sampling method that groups berries by firmness to the touch and visible skin color to study the sequence of physical and chemical changes occurring at the onset of and during ripening. Method robustness and reproducibility were tested by measuring berry weight, diameter, deformation, and total soluble solids (TSS) in samples collected from 10 wine, table, and juice grape cultivars varying in skin color. Additionally, Syrah berries sampled by five different individuals were compared in one year, and Syrah and Merlot berry samples and cluster images were evaluated over three years to account for environmental variation. Merlot berries collected in one year were classified into seven developmental stages to measure changes in berry weight, elastic modulus, TSS, titratable acidity (TA), pH, malate, tartrate, and anthocyanins. Stratified sampling reliably differentiated among developmental stages when applied by different individuals and in different cultivars and years. Once the berries softened, they took 11 to 14 days to complete their color change. Softening occurred mostly before sugar accumulation and renewed berry expansion began. Sugar accumulation was concurrent with malate degradation, but its onset preceded anthocyanin accumulation. The increase in TSS was closely associated with decreases in elastic modulus, TA, and malate and increases in berry weight, skin mass per area ratio, and pH. Ripening-related changes in TA and pH were strongly driven by changes in malate but not tartrate. The stratified sampling method allows novel insights into the timing of physical and chemical changes that occur in grape berries during the period commonly referred to as veraison.
{"title":"Soft, Sweet, and Colorful: Stratified Sampling Reveals Sequence of Events at the Onset of Grape Ripening","authors":"E. Hernández-Montes, Yun Zhang, B. Chang, N. Shcherbatyuk, M. Keller","doi":"10.5344/ajev.2020.20050","DOIUrl":"https://doi.org/10.5344/ajev.2020.20050","url":null,"abstract":"Asynchronous development of grape berries leads to high variation among berry samples collected during veraison. We applied a stratified sampling method that groups berries by firmness to the touch and visible skin color to study the sequence of physical and chemical changes occurring at the onset of and during ripening. Method robustness and reproducibility were tested by measuring berry weight, diameter, deformation, and total soluble solids (TSS) in samples collected from 10 wine, table, and juice grape cultivars varying in skin color. Additionally, Syrah berries sampled by five different individuals were compared in one year, and Syrah and Merlot berry samples and cluster images were evaluated over three years to account for environmental variation. Merlot berries collected in one year were classified into seven developmental stages to measure changes in berry weight, elastic modulus, TSS, titratable acidity (TA), pH, malate, tartrate, and anthocyanins. Stratified sampling reliably differentiated among developmental stages when applied by different individuals and in different cultivars and years. Once the berries softened, they took 11 to 14 days to complete their color change. Softening occurred mostly before sugar accumulation and renewed berry expansion began. Sugar accumulation was concurrent with malate degradation, but its onset preceded anthocyanin accumulation. The increase in TSS was closely associated with decreases in elastic modulus, TA, and malate and increases in berry weight, skin mass per area ratio, and pH. Ripening-related changes in TA and pH were strongly driven by changes in malate but not tartrate. The stratified sampling method allows novel insights into the timing of physical and chemical changes that occur in grape berries during the period commonly referred to as veraison.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"137 - 151"},"PeriodicalIF":1.9,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47299481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Pérez-Magariño, Estela Cano-Mozo, Clara Albors, Antonio Santos, E. Navascués
The production of wines with low biogenic amine (BA) concentrations is a current concern in the wine sector, and strategies to avoid the formation of BAs during winemaking are of particular interest. The aim of this work was to determine the influence of selected autochthonous Oenococcus oeni lactic acid bacteria (LAB) on the BA content in red wines and their prevalence against the indigenous microbiota to avoid BA formation. Sixty-seven red wines were produced at industrial scale under real winemaking conditions for three consecutive vintages. For each wine, we determined LAB implantation and the BA concentrations at various stages of the winemaking process. The results clearly indicated that the use of selected O. oeni strains that are unable to produce BA, in combination with adapted biomass production, is a good strategy to control histamine production in wines. These practices, carried out over three consecutive years, were also observed to ensure the persistence of the selected autochthonous O. oeni strain (CECT 9749) against other indigenous microbiota in the entire winery. Furthermore, analysis of BA content during wine aging in barrels indicated that low BA content was maintained, resulting in healthier wines for the consumer.
{"title":"Autochthonous Oenococcus oeni Strain to Avoid Histamine Formation in Red Wines: A Study in Real Winemaking Conditions","authors":"S. Pérez-Magariño, Estela Cano-Mozo, Clara Albors, Antonio Santos, E. Navascués","doi":"10.5344/ajev.2020.20010","DOIUrl":"https://doi.org/10.5344/ajev.2020.20010","url":null,"abstract":"The production of wines with low biogenic amine (BA) concentrations is a current concern in the wine sector, and strategies to avoid the formation of BAs during winemaking are of particular interest. The aim of this work was to determine the influence of selected autochthonous Oenococcus oeni lactic acid bacteria (LAB) on the BA content in red wines and their prevalence against the indigenous microbiota to avoid BA formation. Sixty-seven red wines were produced at industrial scale under real winemaking conditions for three consecutive vintages. For each wine, we determined LAB implantation and the BA concentrations at various stages of the winemaking process. The results clearly indicated that the use of selected O. oeni strains that are unable to produce BA, in combination with adapted biomass production, is a good strategy to control histamine production in wines. These practices, carried out over three consecutive years, were also observed to ensure the persistence of the selected autochthonous O. oeni strain (CECT 9749) against other indigenous microbiota in the entire winery. Furthermore, analysis of BA content during wine aging in barrels indicated that low BA content was maintained, resulting in healthier wines for the consumer.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"170 - 180"},"PeriodicalIF":1.9,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49283305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sarah E. Mayfield, R. Threlfall, Dorothea Leis, L. Howard, E. Leitner, J. Clark
Enchantment is a Vitis hybrid released from the University of Arkansas System Division of Agriculture winegrape breeding program in 2016. This new teinturier cultivar has potential for producing high-quality wines. The effects of oak addition (no oak, American oak, or French oak) and aging on Enchantment wine attributes were evaluated in 2017 and 2018. Enchantment grapes were harvested in August of both years for wine production. The 2017 and 2018 wines were analyzed initially (0 months) for basic chemistry, anthocyanin, color, and aroma attributes, and 2017 wines were analyzed during storage (0, 6, and 12 months at 15°C) for basic chemistry, anthocyanin, and color attributes. Regardless of oak additions, the initial chemistry of wines in both years was typical for dry wines and remained stable during storage. In both years, malvidin-3-glucoside was the predominant anthocyanin in Enchantment wine, and malvidin-3-glucoside, petunidin-3-glucoside, and delphinidin-3-glucoside comprised >80% of total anthocyanin content. Although anthocyanins decreased during storage, the deep red color of the wine remained stable. In 2018, wines had a deeper, darker red color than in 2017; this corresponded with higher anthocyanin levels in 2018. About 50 volatile aroma compounds were identified in Enchantment wines. There was minimal impact of oak treatment on basic chemistry and anthocyanins, but some impact on color attributes. Oak addition greatly impacted aroma attributes, resulting in wines with oaky, roasted, and caramelized aroma compounds in both years. These results demonstrated the potential of Enchantment winegrapes for producing deeply red-colored, single-varietal wines and blends with oaking and storage potential.
{"title":"Investigating the Winemaking Potential of Enchantment, a New Vitis Hybrid Teinturier Cultivar","authors":"Sarah E. Mayfield, R. Threlfall, Dorothea Leis, L. Howard, E. Leitner, J. Clark","doi":"10.5344/ajev.2021.20052","DOIUrl":"https://doi.org/10.5344/ajev.2021.20052","url":null,"abstract":"Enchantment is a Vitis hybrid released from the University of Arkansas System Division of Agriculture winegrape breeding program in 2016. This new teinturier cultivar has potential for producing high-quality wines. The effects of oak addition (no oak, American oak, or French oak) and aging on Enchantment wine attributes were evaluated in 2017 and 2018. Enchantment grapes were harvested in August of both years for wine production. The 2017 and 2018 wines were analyzed initially (0 months) for basic chemistry, anthocyanin, color, and aroma attributes, and 2017 wines were analyzed during storage (0, 6, and 12 months at 15°C) for basic chemistry, anthocyanin, and color attributes. Regardless of oak additions, the initial chemistry of wines in both years was typical for dry wines and remained stable during storage. In both years, malvidin-3-glucoside was the predominant anthocyanin in Enchantment wine, and malvidin-3-glucoside, petunidin-3-glucoside, and delphinidin-3-glucoside comprised >80% of total anthocyanin content. Although anthocyanins decreased during storage, the deep red color of the wine remained stable. In 2018, wines had a deeper, darker red color than in 2017; this corresponded with higher anthocyanin levels in 2018. About 50 volatile aroma compounds were identified in Enchantment wines. There was minimal impact of oak treatment on basic chemistry and anthocyanins, but some impact on color attributes. Oak addition greatly impacted aroma attributes, resulting in wines with oaky, roasted, and caramelized aroma compounds in both years. These results demonstrated the potential of Enchantment winegrapes for producing deeply red-colored, single-varietal wines and blends with oaking and storage potential.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"194 - 207"},"PeriodicalIF":1.9,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44343807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Canopy sensing in viticulture is widely associated with the term NDVI (normalized difference vegetation index). However, there are many other vegetative indices (VIs) that can be calculated from information captured with visible/near-infrared (NIR) sensors. A proximal canopy sensor was used to survey 27 vineyards in the Lake Erie Concord belt and stratified to collect pruning weights (PW) at a density of ~25 samples per vineyard. Seven VIs were derived from the sensor data and the first principal component (PC1) extracted from a principal components analysis of the seven VIs. The VIs and PC1 were regressed against the local PW measurements and ranked in terms of their goodness-of-fit. Over the 27 vineyards, there was no single VI that outperformed the others, although VIs that used the red-edge band had a slight advantage over VIs using the red band. It is therefore recommended to use the normalized difference red edge index (NDRE) in place of the NDVI when predicting PW from terrestrial-based proximal canopy surveys. The PC1 derived from the decomposition of all seven VIs did appear to convey some benefit to PW prediction compared with a single VI approach, particularly with just NDVI. More research into the potential for multivariate approaches is recommended.
{"title":"Comparison of Different Vegetative Indices for Calibrating Proximal Canopy Sensors to Grapevine Pruning Weight","authors":"J. Taylor, T. Bates","doi":"10.5344/ajev.2021.20042","DOIUrl":"https://doi.org/10.5344/ajev.2021.20042","url":null,"abstract":"Canopy sensing in viticulture is widely associated with the term NDVI (normalized difference vegetation index). However, there are many other vegetative indices (VIs) that can be calculated from information captured with visible/near-infrared (NIR) sensors. A proximal canopy sensor was used to survey 27 vineyards in the Lake Erie Concord belt and stratified to collect pruning weights (PW) at a density of ~25 samples per vineyard. Seven VIs were derived from the sensor data and the first principal component (PC1) extracted from a principal components analysis of the seven VIs. The VIs and PC1 were regressed against the local PW measurements and ranked in terms of their goodness-of-fit. Over the 27 vineyards, there was no single VI that outperformed the others, although VIs that used the red-edge band had a slight advantage over VIs using the red band. It is therefore recommended to use the normalized difference red edge index (NDRE) in place of the NDVI when predicting PW from terrestrial-based proximal canopy surveys. The PC1 derived from the decomposition of all seven VIs did appear to convey some benefit to PW prediction compared with a single VI approach, particularly with just NDVI. More research into the potential for multivariate approaches is recommended.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"279 - 283"},"PeriodicalIF":1.9,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42965853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Oliver, M. Cooper, M. L. Lewis Ivey, P. Brannen, T. Miles, W. Mahaffee, M. Moyer
In 2019, a national survey of 252 members of the United States grape industry from 20 states assessed knowledge perception of fungicide resistance management, application of that knowledge to vineyard practices, and knowledge acquisition sources. Overall, respondents demonstrated clear understanding of resistance management practices. The specific distribution of responses was influenced by the respondent’s job role, duration of industry experience, and their farming operation size. Nationally, respondents were moderately familiar with the acronym FRAC (Fungicide Resistance Action Committee), with nearly 75% indicating they could identify the FRAC code of a fungicide. They felt moderately competent they could design a fungicide program that adhered to resistance management principles. Respondents identified fungicide resistance as a serious problem nationally, and as a moderate problem in their own vineyards. They ranked practices that include rotating fungicides of different FRAC codes, avoiding multiple sequential applications of the same trade name or FRAC code, tank mixing with different FRAC codes, using multisite products in a spray program, routine sprayer maintenance and calibration, and good canopy management as very-to-extremely important in managing fungicide resistance; whereas practices such as rotating between trade names and tank mixing different trade names ranked slightly important. Respondents identified university-based extension programs as the primary information resource for fungicide efficacy and fungicide stewardship (resistance management). To maximize potential effect, these results suggest that future educational efforts should be aimed at improving practices for fungicide resistance stewardship and should align with the knowledge-base and demographic factors of the target audience—particularly their job role, experience, and size of operation.
{"title":"Assessing the United States Grape Industry’s Understanding of Fungicide Resistance Mitigation Practices","authors":"C. Oliver, M. Cooper, M. L. Lewis Ivey, P. Brannen, T. Miles, W. Mahaffee, M. Moyer","doi":"10.5344/ajev.2021.20062","DOIUrl":"https://doi.org/10.5344/ajev.2021.20062","url":null,"abstract":"In 2019, a national survey of 252 members of the United States grape industry from 20 states assessed knowledge perception of fungicide resistance management, application of that knowledge to vineyard practices, and knowledge acquisition sources. Overall, respondents demonstrated clear understanding of resistance management practices. The specific distribution of responses was influenced by the respondent’s job role, duration of industry experience, and their farming operation size. Nationally, respondents were moderately familiar with the acronym FRAC (Fungicide Resistance Action Committee), with nearly 75% indicating they could identify the FRAC code of a fungicide. They felt moderately competent they could design a fungicide program that adhered to resistance management principles. Respondents identified fungicide resistance as a serious problem nationally, and as a moderate problem in their own vineyards. They ranked practices that include rotating fungicides of different FRAC codes, avoiding multiple sequential applications of the same trade name or FRAC code, tank mixing with different FRAC codes, using multisite products in a spray program, routine sprayer maintenance and calibration, and good canopy management as very-to-extremely important in managing fungicide resistance; whereas practices such as rotating between trade names and tank mixing different trade names ranked slightly important. Respondents identified university-based extension programs as the primary information resource for fungicide efficacy and fungicide stewardship (resistance management). To maximize potential effect, these results suggest that future educational efforts should be aimed at improving practices for fungicide resistance stewardship and should align with the knowledge-base and demographic factors of the target audience—particularly their job role, experience, and size of operation.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"181 - 193"},"PeriodicalIF":1.9,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71029586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ingrid Weilack, Christina Schmitz, J. Harbertson, Fabian Weber
Condensed tannins and polymeric pigments are essential red wine components that contribute to color stability, taste, and mouthfeel. Phenolic polymers in red wine consist of flavan-3-ol monomers and anthocyanins and cause the perception of astringency. Due to the chemical heterogeneity of proanthocyanidin polymers, analytical tools to determine the polymers’ structural features are limited. Incorporation of anthocyanins increases the structural complexity even more and makes it almost impossible to assess the influence of structure on the perceived astringency. To better understand the structural diversity of red wine polymers, this study combines forced aging and FLASH-fractionation of polyphenolic wine extracts to reveal the relationship between phenolic polymers and two physicochemical properties: polarity and hydrophilicity. Red wine fractions were characterized using polarity, the octanol-water partitioning coefficient, protein precipitation assay, ultra high-performance liquid chromatography-mass spectrometry, and color. Tannin concentrations in wine decreased during forced aging and were constant in the corresponding extracts, suggesting alteration of the precipitation behavior. A simultaneous increase in precipitable polymeric pigments leads to the assumption that incorporating anthocyanins into tannin molecules alters their interactions with red wine polysaccharides and proteins, lowering tannin readings. Finding tannins and polymeric pigments in different FLASH-fractions indicates that precipitability of polymers is affected by their physicochemical properties, which in turn depend on the degree of polymerization as well as degree of pigmentation. The results of this study show that red wine astringency and its sub-qualities may be related to the increase in precipitable polymeric pigments during forced red wine aging and their putative enhanced interaction with wine polysaccharides, increasing understanding of astringency mechanisms.
{"title":"Effect of Structural Transformations on Precipitability and Polarity of Red Wine Phenolic Polymers","authors":"Ingrid Weilack, Christina Schmitz, J. Harbertson, Fabian Weber","doi":"10.5344/ajev.2021.20064","DOIUrl":"https://doi.org/10.5344/ajev.2021.20064","url":null,"abstract":"Condensed tannins and polymeric pigments are essential red wine components that contribute to color stability, taste, and mouthfeel. Phenolic polymers in red wine consist of flavan-3-ol monomers and anthocyanins and cause the perception of astringency. Due to the chemical heterogeneity of proanthocyanidin polymers, analytical tools to determine the polymers’ structural features are limited. Incorporation of anthocyanins increases the structural complexity even more and makes it almost impossible to assess the influence of structure on the perceived astringency. To better understand the structural diversity of red wine polymers, this study combines forced aging and FLASH-fractionation of polyphenolic wine extracts to reveal the relationship between phenolic polymers and two physicochemical properties: polarity and hydrophilicity. Red wine fractions were characterized using polarity, the octanol-water partitioning coefficient, protein precipitation assay, ultra high-performance liquid chromatography-mass spectrometry, and color. Tannin concentrations in wine decreased during forced aging and were constant in the corresponding extracts, suggesting alteration of the precipitation behavior. A simultaneous increase in precipitable polymeric pigments leads to the assumption that incorporating anthocyanins into tannin molecules alters their interactions with red wine polysaccharides and proteins, lowering tannin readings. Finding tannins and polymeric pigments in different FLASH-fractions indicates that precipitability of polymers is affected by their physicochemical properties, which in turn depend on the degree of polymerization as well as degree of pigmentation. The results of this study show that red wine astringency and its sub-qualities may be related to the increase in precipitable polymeric pigments during forced red wine aging and their putative enhanced interaction with wine polysaccharides, increasing understanding of astringency mechanisms.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"230 - 239"},"PeriodicalIF":1.9,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42046693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Natacha Cureau, R. Threlfall, Franck Carbonero, L. Howard, Laura Lavefve
Microbial communities during grape wine fermentations are diverse and dynamic. High-throughput sequencing (molecular methods enabling precise identification of microbial communities) was used to identify fungal diversity during fermentation of grape juice with different sulfite levels and yeast inoculations. Fermentation (0, 14, and 21 days) was evaluated in two grape varieties, Noble (Vitis rotundifolia) and Vignoles (Vitis hybrid), fermented at three sulfite levels (0, 10, and 20 mg/L) with three yeast inoculations (uninoculated, Saccharomyces cerevisiae, and Torulaspora delbrueckii). Fungal taxonomy of both varieties included six to seven phyla and 115 to 129 genera. The indigenous microbiota was affected by sulfite level and yeast inoculation and varied by grape variety. Sulfite levels had minimal effect on fungal communities but did affect fermentation dynamics. Increasing sulfite additions did not affect the fermentation performance of S. cerevisiae but did affect the fermentation of uninoculated juice and T. delbrueckii-inoculated juice. The primary fungal genera (Podosphaera, Candida, Phialemoniopsis, and Meyerozyma)—those present at a relative abundance >1%—were the same for both varieties but at different relative abundance. Similar fungal diversity patterns were observed for both varieties, with a decrease in diversity at day 14 and an increase at day 21 of fermentation. Juices inoculated with T. delbrueckii were rapidly colonized by Torulaspora spp. at day 0 for both varieties, whereas Saccharomyces spp. dominated by day 14 when inoculated with S. cerevisiae, especially in Noble. The most abundant genera in uninoculated juice were Hanseniaspora and Zygoascus for Noble and Hanseniaspora and Saccharomyces for Vignoles. Understanding grape juice microbial communities and the dynamics of these communities during fermentation provides insight for wine production using spontaneous fermentations or non-Saccharomyces species and information on the effect of sulfur dioxide on these novel fermentations.
{"title":"Fungal Diversity and Dynamics during Grape Wine Fermentations with Different Sulfite Levels and Yeast Inoculations","authors":"Natacha Cureau, R. Threlfall, Franck Carbonero, L. Howard, Laura Lavefve","doi":"10.5344/ajev.2021.20054","DOIUrl":"https://doi.org/10.5344/ajev.2021.20054","url":null,"abstract":"Microbial communities during grape wine fermentations are diverse and dynamic. High-throughput sequencing (molecular methods enabling precise identification of microbial communities) was used to identify fungal diversity during fermentation of grape juice with different sulfite levels and yeast inoculations. Fermentation (0, 14, and 21 days) was evaluated in two grape varieties, Noble (Vitis rotundifolia) and Vignoles (Vitis hybrid), fermented at three sulfite levels (0, 10, and 20 mg/L) with three yeast inoculations (uninoculated, Saccharomyces cerevisiae, and Torulaspora delbrueckii). Fungal taxonomy of both varieties included six to seven phyla and 115 to 129 genera. The indigenous microbiota was affected by sulfite level and yeast inoculation and varied by grape variety. Sulfite levels had minimal effect on fungal communities but did affect fermentation dynamics. Increasing sulfite additions did not affect the fermentation performance of S. cerevisiae but did affect the fermentation of uninoculated juice and T. delbrueckii-inoculated juice. The primary fungal genera (Podosphaera, Candida, Phialemoniopsis, and Meyerozyma)—those present at a relative abundance >1%—were the same for both varieties but at different relative abundance. Similar fungal diversity patterns were observed for both varieties, with a decrease in diversity at day 14 and an increase at day 21 of fermentation. Juices inoculated with T. delbrueckii were rapidly colonized by Torulaspora spp. at day 0 for both varieties, whereas Saccharomyces spp. dominated by day 14 when inoculated with S. cerevisiae, especially in Noble. The most abundant genera in uninoculated juice were Hanseniaspora and Zygoascus for Noble and Hanseniaspora and Saccharomyces for Vignoles. Understanding grape juice microbial communities and the dynamics of these communities during fermentation provides insight for wine production using spontaneous fermentations or non-Saccharomyces species and information on the effect of sulfur dioxide on these novel fermentations.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"240 - 256"},"PeriodicalIF":1.9,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46754596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Brettanomyces yeasts remain one of the most important spoilage issues facing the global wine industry. Despite their ubiquitous association with wine and wineries from around the world, there is almost no information on the occurrence of Brettanomyces in vineyards. In this study we used enrichment culturing to successfully isolate Brettanomyces yeasts from 12 of 149 grape berry cluster samples obtained from a vineyard in Oregon over two harvest seasons. This low rate of recovery was consistent with another recent study performed in Italy (Oro et al. 2019) and suggests that Brettanomyces is not a prevalent vineyard yeast genus. In addition to Brettanomyces, we recovered non-Saccharomyces isolates from a further 39 samples. These were predominantly from genera infrequently described in the context of vineyards and winemaking fungal communities, such as Nakazawea, Kazachstania, Lodderomcyes, and Ogataea. By evaluating relative growth capacity and direct competitive fitness, we showed that while some vineyard non-Saccharomyces yeasts are likely to be out-competed in enrichment media by Brettanomyces, others can interfere with Brettanomyces recovery. This may partly explain why Brettanomyces vineyard populations are rarely described. Our results pave the way for further studies of Brettanomyces from non-fermentation origins and demonstrate that enrichment culturing can be applied to reveal other rare vineyard yeast populations.
{"title":"Enrichment of Brettanomyces and Other Non-Saccharomyces Fermentative Yeasts from Vineyard Samples in Oregon","authors":"Kevin Pigao, R. O'Donnell, J. Osborne, C. Curtin","doi":"10.5344/ajev.2021.20071","DOIUrl":"https://doi.org/10.5344/ajev.2021.20071","url":null,"abstract":"Brettanomyces yeasts remain one of the most important spoilage issues facing the global wine industry. Despite their ubiquitous association with wine and wineries from around the world, there is almost no information on the occurrence of Brettanomyces in vineyards. In this study we used enrichment culturing to successfully isolate Brettanomyces yeasts from 12 of 149 grape berry cluster samples obtained from a vineyard in Oregon over two harvest seasons. This low rate of recovery was consistent with another recent study performed in Italy (Oro et al. 2019) and suggests that Brettanomyces is not a prevalent vineyard yeast genus. In addition to Brettanomyces, we recovered non-Saccharomyces isolates from a further 39 samples. These were predominantly from genera infrequently described in the context of vineyards and winemaking fungal communities, such as Nakazawea, Kazachstania, Lodderomcyes, and Ogataea. By evaluating relative growth capacity and direct competitive fitness, we showed that while some vineyard non-Saccharomyces yeasts are likely to be out-competed in enrichment media by Brettanomyces, others can interfere with Brettanomyces recovery. This may partly explain why Brettanomyces vineyard populations are rarely described. Our results pave the way for further studies of Brettanomyces from non-fermentation origins and demonstrate that enrichment culturing can be applied to reveal other rare vineyard yeast populations.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"257 - 266"},"PeriodicalIF":1.9,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49194541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Washington winegrape growers are rapidly adopting vineyard management technologies such as mechanical pruners and harvesters, but they have been slower to adopt new chemical application technologies. This study generated technical information about commercial over-the-row sprayers and their deposition and drift to allow growers to select and optimize sprayers for different vineyard systems and winegrape canopies. Three commercial sprayer technologies (multi-fan heads, pneumatic, and electrostatic) were evaluated for canopy deposition and drift in the 2016 and 2017 production seasons. Data were collected in Vitis vinifera Chardonnay and Riesling vineyards at two application timings, early season and midseason, to determine sprayer deposition patterns in opposed and unopposed applications and in-field aerial and ground drifts. All sprayer technologies showed consistent in-canopy deposition and drift patterns at both application timings. Regardless of sprayer technology, the most deposition was in the upper canopy rather than in the fruiting zone. Similarly, the most aerial and ground drift occurred in the row closest to the sprayed row, indicating that drift is relatively low with all three evaluated sprayer technologies.
{"title":"Assessment of Three Commercial Over-the-Row Sprayer Technologies in Eastern Washington Vineyards","authors":"Mary L. McCoy, G. Hoheisel, L. Khot, M. Moyer","doi":"10.5344/ajev.2021.20058","DOIUrl":"https://doi.org/10.5344/ajev.2021.20058","url":null,"abstract":"Washington winegrape growers are rapidly adopting vineyard management technologies such as mechanical pruners and harvesters, but they have been slower to adopt new chemical application technologies. This study generated technical information about commercial over-the-row sprayers and their deposition and drift to allow growers to select and optimize sprayers for different vineyard systems and winegrape canopies. Three commercial sprayer technologies (multi-fan heads, pneumatic, and electrostatic) were evaluated for canopy deposition and drift in the 2016 and 2017 production seasons. Data were collected in Vitis vinifera Chardonnay and Riesling vineyards at two application timings, early season and midseason, to determine sprayer deposition patterns in opposed and unopposed applications and in-field aerial and ground drifts. All sprayer technologies showed consistent in-canopy deposition and drift patterns at both application timings. Regardless of sprayer technology, the most deposition was in the upper canopy rather than in the fruiting zone. Similarly, the most aerial and ground drift occurred in the row closest to the sprayed row, indicating that drift is relatively low with all three evaluated sprayer technologies.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"217 - 229"},"PeriodicalIF":1.9,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41524182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andréanne Hébert-Haché, D. Inglis, Belinda Kemp, James J. Willwerth
Cold damage is a threat to grapegrowers worldwide. Cold hardiness varies across Vitis vinifera cultivars, but the influence of clone and rootstock selection on this trait is unclear. Five clone × rootstock combinations of Riesling (clone 49 × Riparia Gloire [RG], 49 × SO4 Teleki, clone 239 × RG, 239 × SO4, and 239 × Couderc 3309) and four clones of Sauvignon blanc (clone 242, 297, 376, and 530 on SO4 Teleki rootstock) were evaluated over three dormant seasons (2016/17, 2017/18, and 2018/19). Bud cold hardiness was quantified every two to four weeks by differential thermal analysis and reported as low temperature exotherms. Yield and pruning weights were determined every year. Rootstock did not influence the cold hardiness of Riesling buds consistently, although clone 239 was generally hardier than clone 49. Significant clone × rootstock interactions were observed more frequently in the first year of the study. No consistent differences were observed between Sauvignon blanc clones, although clone 242 and 297 were often among the least-hardy clones. Differences in hardiness were not consistently related to yield, pruning weight, or crop load in the prior growing season. This study demonstrates the importance of both clone and rootstock selection in cool climate regions where freeze injury may occur. Future research should consider the clone identity and the possibility of a clone × rootstock interaction when comparing the cold hardiness of different cultivars.
{"title":"Clone and Rootstock Interactions Influence the Cold Hardiness of Vitis vinifera cvs. Riesling and Sauvignon blanc","authors":"Andréanne Hébert-Haché, D. Inglis, Belinda Kemp, James J. Willwerth","doi":"10.5344/ajev.2020.20025","DOIUrl":"https://doi.org/10.5344/ajev.2020.20025","url":null,"abstract":"Cold damage is a threat to grapegrowers worldwide. Cold hardiness varies across Vitis vinifera cultivars, but the influence of clone and rootstock selection on this trait is unclear. Five clone × rootstock combinations of Riesling (clone 49 × Riparia Gloire [RG], 49 × SO4 Teleki, clone 239 × RG, 239 × SO4, and 239 × Couderc 3309) and four clones of Sauvignon blanc (clone 242, 297, 376, and 530 on SO4 Teleki rootstock) were evaluated over three dormant seasons (2016/17, 2017/18, and 2018/19). Bud cold hardiness was quantified every two to four weeks by differential thermal analysis and reported as low temperature exotherms. Yield and pruning weights were determined every year. Rootstock did not influence the cold hardiness of Riesling buds consistently, although clone 239 was generally hardier than clone 49. Significant clone × rootstock interactions were observed more frequently in the first year of the study. No consistent differences were observed between Sauvignon blanc clones, although clone 242 and 297 were often among the least-hardy clones. Differences in hardiness were not consistently related to yield, pruning weight, or crop load in the prior growing season. This study demonstrates the importance of both clone and rootstock selection in cool climate regions where freeze injury may occur. Future research should consider the clone identity and the possibility of a clone × rootstock interaction when comparing the cold hardiness of different cultivars.","PeriodicalId":7461,"journal":{"name":"American Journal of Enology and Viticulture","volume":"72 1","pages":"126 - 136"},"PeriodicalIF":1.9,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43869162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}