The Experts below are selected from a list of 15735 Experts worldwide ranked by ideXlab platform
Andrew G. Reynolds - One of the best experts on this subject based on the ideXlab platform.
-
Crop Level and Harvest Date Impact Composition of Four Ontario Winegrape Cultivars. I. Yield, Fruit, and Wine Composition
American Journal of Enology and Viticulture, 2017Co-Authors: Luis Hugo Moreno Luna, Andrew G. Reynolds, Frederick Di ProfioAbstract:Pinot gris, Riesling, Cabernet franc, and Cabernet Sauvignon vines from a single vineyard in Virgil, Ontario were subjected to two crop levels, full crop (FC) and half crop (HC), in which crop was reduced in HC to one basal cluster per shoot at veraison. Crop level treatments were combined with three Harvest Dates: T0 (commercial Harvest), T1 (three weeks after T0), and T2 (six weeks after T0), all with subsequent wine production. Berries, must, and wine were analyzed. Reductions in crop led to an increase in Brix, reduced yield, and cluster number in all cultivars, and increased cluster weight in Cabernet franc. Delayed Harvest Date also increased Brix and pH and reduced titratable acidity (TA) and berry weight. Effect of Harvest Date in berries carried over to musts and wines: increased pH and TA in T2 treatments was associated with reduced anthocyanins, phenols, and color intensity in red cultivars. Delayed Harvest Date had a greater magnitude of effect than crop reduction; thus, maintaining a full crop with a later Harvest Date might have a greater beneficial impact on potential wine quality than reducing crop level.
-
Harvest Date and crop level influence sensory and chemical profiles of Ontario Vidal blanc and Riesling icewines.
Food research international (Ottawa Ont.), 2016Co-Authors: Amy J. Bowen, Andrew G. Reynolds, Isabelle LesschaeveAbstract:There is likelihood that periods of freezing and thawing endured by icewine grapes change their chemical and sensory profiles. The experimental objective was to determine the influence of Harvest Date and crop level on icewine sensory profiles and their relationships with chemical variables. Riesling and Vidal blanc (hereinafter "Vidal") icewines were made from four Harvest Dates in 2004-2005; Harvest 1 (H1): 19 December; H2: 29 December; H3: 18 January; H4: 11 February (Vidal only). Riesling and Vidal icewines were additionally made from three crop level treatments [control (fully cropped), fruit set cluster thinning (i.e. partial fruit removal) to one (basal) cluster per shoot, veraison cluster thinning] and were evaluated over two seasons (2003-2004; 2004-2005). Triangle tests showed differences between Harvest Date and crop level treatments (both cultivars). Ten and 11 aroma/flavor attributes differed for Vidal and Riesling Harvest Date icewines, respectively, based upon descriptive analysis by 14 trained tasters. For Vidal, later Harvest Dates had higher aroma/flavor intensities than H1. Riesling H1 wines had highest fresh fruit descriptor intensities whereas H3 wines were highest for dried fruit and nutty descriptors. Partial least squares regression (PLS) found Vidal icewines described by dried fruit/raisin and honey flavors and viscosity; these attributes were correlated to several aroma compounds and associated with later Harvest Dates. Sensory differences existed between crop level treatments; thinned treatments had higher fruity, honey, sherry and nut aroma/flavor intensities (both cultivars). PLS showed that sherry flavor was the most important explanatory variable in 2003, and correlated 4-vinylguaiacol and banana flavor in 2004. Overall, Harvest Date and crop level both affected sensory profiles and chemical composition of Niagara Peninsula icewines.
-
Impact of crop level and Harvest Date on anthocyanins and phenolics of red wines from Ontario
Canadian Journal of Plant Science, 2016Co-Authors: Jessa A.k. Black, Frederick Di Profio, Valentine Le Dauphin, Luis Hugo Moreno, Andrew G. ReynoldsAbstract:Cabernet Sauvignon (CS) and Cabernet franc (CF) vines were subjected to two crop levels (full, half) and three Harvest Dates (earliest to latest; T0, T1, T2) over two vintages. Wines were analyzed for anthocyanins, phenolics, and proanthocyanidins. Crop level increased CS hue (2011–2012), increased CS pH and reduced CS color intensity (2012), and reduced CF hue (2012). Harvest Date had a greater effect than crop level, with many treatment interactions. Half crop (2011) increased three CS anthocyanins plus procyanidin B. Extended Harvest increased eight compounds. Quercetin and (+)-catechin decreased in T1. Crop reduction (2012) increased malvidin-3-coumarylglucoside and (+)-catechin, but decreased petunidin and delphinidin-3-coumarylglucoside. Harvest Date (2012) impacted all but two compounds, with the highest anthocyanin concentrations in T1 wines. Gallic acid, (+)-catechin and resveratrol increased with Harvest Date, while three phenols decreased. Half crop (2011) increased CF peonidin. Extended harves...
-
Aroma compounds in Ontario Vidal and Riesling icewines. I. Effects of Harvest Date.
Food research international (Ottawa Ont.), 2015Co-Authors: Amy J. Bowen, Andrew G. ReynoldsAbstract:Icewine is a sweet dessert wine made from pressing grapes naturally frozen on the vines. It is likely that freeze/thaw cycles endured by icewine grapes change their chemical and sensory profiles due to climatic events. Our objective was to determine the influence of Harvest Date on icewine must and wine basic chemical variables and aroma compounds. Riesling and Vidal icewines were made from grapes picked between December 2004 and February 2005; Harvest 1 (H1): 19 December; Harvest 2: 29 December; Harvest 3 (H3): 18 January; and Harvest 4 (H4): 11 February (Vidal only). Icewine musts differed in titratable acidity and pH (Vidal only). All basic wine chemical analytes differed across Harvest Dates. All aroma compounds differed in Vidal and Riesling wines. Highest concentrations for most aroma compounds were in the last Harvest Date; 16 of 24 for Vidal and 17 of 23 for Riesling. The latest Harvest Date had highest ethyl isobutyrate, ethyl 3-methylbutyrate, 1-hexanol, 1-octen-3-ol, 1-octanol, cis-rose oxide, nerol oxide, ethyl benzoate, ethyl phenylacetate, γ-nonalactone and β-damascenone. H1 had highest ethyl butyrate, ethyl hexanoate, linalool, 4-vinylguaiacol and ethyl octanoate. Based on odor activity values, the most odor-potent compounds were β-damascenone, cis-rose oxide, 1-octen-3-ol, ethyl octanoate, ethyl hexanoate, and 4-vinylguaiacol across Harvest Dates. PCA found most aroma compounds associated with the last Harvest Date, 4-vinylguaicol excepted, which was associated with H1. Harvest Date was considered a discriminating dimension using canonical variant analysis for volatile compounds.
-
Terpene response to pressing, Harvest Date, and skin contact in Vitis vinifera
HortScience, 1993Co-Authors: Andrew G. Reynolds, Douglas A. Wardle, Marjorie DeverAbstract:Vitis vinifera L. cultivars Muller-Thurgau, Muscat Ottonel, Gewurztraminer, and Kerner were studied for 1 year to document changes in fruit terpene levels from berry stage to free-run and press-juice stages. Substantial amounts of free volatile terpenes (FVTs) and potentially volatile terpenes (PVTs) were lost between berry and juice stages. PVTs were higher in press juices of 'Gewurztraminer' and 'Muscat Ottonel' than in free- run juices. In another experiment, juices from 'Miiller-Thurgau', 'Muscat Ottonel', 'Kerner', 'Optima', 'Pearl of Csaba', and 'Siegerrebe', Harvested 10 to 20 days after a designated initial Harvest Date, contained higher FVTs and PVTs than initially. A third experiment with 'Kerner', 'Muller-Thurgau ', 'Optima', and 'Siegerrebe' found highest FVTs and PVTs in juices from grapes subjected to skin contact compared with grapes crushed and immediately pressed. Sensory evaluation showed aroma differences between wines from free-run and press juices of 'Miiller-Thurgau' and 'Muscat Ottonel', aroma and flavor differences due to Harvest Date for all cultivars except 'Pearl of Csaba', and aroma and flavor differences due to skin contact for 'Siegerrebe'.
Amy J. Bowen - One of the best experts on this subject based on the ideXlab platform.
-
Harvest Date and crop level influence sensory and chemical profiles of Ontario Vidal blanc and Riesling icewines.
Food research international (Ottawa Ont.), 2016Co-Authors: Amy J. Bowen, Andrew G. Reynolds, Isabelle LesschaeveAbstract:There is likelihood that periods of freezing and thawing endured by icewine grapes change their chemical and sensory profiles. The experimental objective was to determine the influence of Harvest Date and crop level on icewine sensory profiles and their relationships with chemical variables. Riesling and Vidal blanc (hereinafter "Vidal") icewines were made from four Harvest Dates in 2004-2005; Harvest 1 (H1): 19 December; H2: 29 December; H3: 18 January; H4: 11 February (Vidal only). Riesling and Vidal icewines were additionally made from three crop level treatments [control (fully cropped), fruit set cluster thinning (i.e. partial fruit removal) to one (basal) cluster per shoot, veraison cluster thinning] and were evaluated over two seasons (2003-2004; 2004-2005). Triangle tests showed differences between Harvest Date and crop level treatments (both cultivars). Ten and 11 aroma/flavor attributes differed for Vidal and Riesling Harvest Date icewines, respectively, based upon descriptive analysis by 14 trained tasters. For Vidal, later Harvest Dates had higher aroma/flavor intensities than H1. Riesling H1 wines had highest fresh fruit descriptor intensities whereas H3 wines were highest for dried fruit and nutty descriptors. Partial least squares regression (PLS) found Vidal icewines described by dried fruit/raisin and honey flavors and viscosity; these attributes were correlated to several aroma compounds and associated with later Harvest Dates. Sensory differences existed between crop level treatments; thinned treatments had higher fruity, honey, sherry and nut aroma/flavor intensities (both cultivars). PLS showed that sherry flavor was the most important explanatory variable in 2003, and correlated 4-vinylguaiacol and banana flavor in 2004. Overall, Harvest Date and crop level both affected sensory profiles and chemical composition of Niagara Peninsula icewines.
-
Aroma compounds in Ontario Vidal and Riesling icewines. I. Effects of Harvest Date.
Food research international (Ottawa Ont.), 2015Co-Authors: Amy J. Bowen, Andrew G. ReynoldsAbstract:Icewine is a sweet dessert wine made from pressing grapes naturally frozen on the vines. It is likely that freeze/thaw cycles endured by icewine grapes change their chemical and sensory profiles due to climatic events. Our objective was to determine the influence of Harvest Date on icewine must and wine basic chemical variables and aroma compounds. Riesling and Vidal icewines were made from grapes picked between December 2004 and February 2005; Harvest 1 (H1): 19 December; Harvest 2: 29 December; Harvest 3 (H3): 18 January; and Harvest 4 (H4): 11 February (Vidal only). Icewine musts differed in titratable acidity and pH (Vidal only). All basic wine chemical analytes differed across Harvest Dates. All aroma compounds differed in Vidal and Riesling wines. Highest concentrations for most aroma compounds were in the last Harvest Date; 16 of 24 for Vidal and 17 of 23 for Riesling. The latest Harvest Date had highest ethyl isobutyrate, ethyl 3-methylbutyrate, 1-hexanol, 1-octen-3-ol, 1-octanol, cis-rose oxide, nerol oxide, ethyl benzoate, ethyl phenylacetate, γ-nonalactone and β-damascenone. H1 had highest ethyl butyrate, ethyl hexanoate, linalool, 4-vinylguaiacol and ethyl octanoate. Based on odor activity values, the most odor-potent compounds were β-damascenone, cis-rose oxide, 1-octen-3-ol, ethyl octanoate, ethyl hexanoate, and 4-vinylguaiacol across Harvest Dates. PCA found most aroma compounds associated with the last Harvest Date, 4-vinylguaicol excepted, which was associated with H1. Harvest Date was considered a discriminating dimension using canonical variant analysis for volatile compounds.
Isabelle Lesschaeve - One of the best experts on this subject based on the ideXlab platform.
-
Harvest Date and crop level influence sensory and chemical profiles of Ontario Vidal blanc and Riesling icewines.
Food research international (Ottawa Ont.), 2016Co-Authors: Amy J. Bowen, Andrew G. Reynolds, Isabelle LesschaeveAbstract:There is likelihood that periods of freezing and thawing endured by icewine grapes change their chemical and sensory profiles. The experimental objective was to determine the influence of Harvest Date and crop level on icewine sensory profiles and their relationships with chemical variables. Riesling and Vidal blanc (hereinafter "Vidal") icewines were made from four Harvest Dates in 2004-2005; Harvest 1 (H1): 19 December; H2: 29 December; H3: 18 January; H4: 11 February (Vidal only). Riesling and Vidal icewines were additionally made from three crop level treatments [control (fully cropped), fruit set cluster thinning (i.e. partial fruit removal) to one (basal) cluster per shoot, veraison cluster thinning] and were evaluated over two seasons (2003-2004; 2004-2005). Triangle tests showed differences between Harvest Date and crop level treatments (both cultivars). Ten and 11 aroma/flavor attributes differed for Vidal and Riesling Harvest Date icewines, respectively, based upon descriptive analysis by 14 trained tasters. For Vidal, later Harvest Dates had higher aroma/flavor intensities than H1. Riesling H1 wines had highest fresh fruit descriptor intensities whereas H3 wines were highest for dried fruit and nutty descriptors. Partial least squares regression (PLS) found Vidal icewines described by dried fruit/raisin and honey flavors and viscosity; these attributes were correlated to several aroma compounds and associated with later Harvest Dates. Sensory differences existed between crop level treatments; thinned treatments had higher fruity, honey, sherry and nut aroma/flavor intensities (both cultivars). PLS showed that sherry flavor was the most important explanatory variable in 2003, and correlated 4-vinylguaiacol and banana flavor in 2004. Overall, Harvest Date and crop level both affected sensory profiles and chemical composition of Niagara Peninsula icewines.
Larry G. Campbell - One of the best experts on this subject based on the ideXlab platform.
-
Impact of storage temperature, storage duration, and Harvest Date on sugarbeet raffinose metabolism
Postharvest Biology and Technology, 2008Co-Authors: Darrin M. Haagenson, Karen L. Klotz, Larry G. CampbellAbstract:Abstract Raffinose negatively impacts sugarbeet ( Beta vulgaris L.) processing by decreasing extractable sucrose yield and altering sucrose crystal morphology which reduces filtration rates and slows processing. Although increased raffinose concentrations have been observed during cold storage, the physiological and biochemical mechanisms associated with raffinose accumulation in sugarbeet are poorly understood. The objective of this study was to characterize the impact of storage temperature, storage duration, and Harvest Date on raffinose metabolism. Field-grown sugarbeets were Harvested 7 September, 27 September, and 26 October 2004, and stored for 2, 10, or 18 weeks at 2 °C or 6 °C. Raffinose concentrations were approximately double at 2 weeks of storage, nearly threefold higher at 10 weeks, and decreased slightly at 18 weeks. Delaying Harvest Date increased raffinose concentration at Harvest (0 weeks), but decreased concentrations at 18 weeks of storage. Storage temperature did not affect crown raffinose concentrations, but root tissues stored at 2 °C had 19% higher raffinose concentrations than at 6 °C. Biosynthetic or catabolic enzyme activities accounted for less than 15% of the variation in raffinose content in storage, although a small positive correlation ( r = 0.28) between raffinose synthase activity and raffinose concentration in root tissues was observed. Galactinol synthase was highly expressed in tissues collected in late October and at 2 weeks of storage, and α-galactosidase activity increased 55% in roots stored for 18 weeks at 6 °C. Factors contributing to sugarbeet raffinose accumulation in storage are complex as raffinose concentrations were impacted by storage duration, Harvest Date, and storage temperature.
J. H. Van Niejenhuis - One of the best experts on this subject based on the ideXlab platform.
-
Prediction of various effects of Harvest Date in sugar beet growing
Journal of Agronomy and Crop Science, 1998Co-Authors: A.b. Smit, Paul C. Struik, J. H. Van NiejenhuisAbstract:One crucial decision in sugar beet growing is determining Harvest Date. This paper focuses on some aspects associated with Harvest Date which have to be included in a decision support system for sugar beet growing. Firstly, a module was created for dirt and crown tare, mainly based on lutum (or clay) and soil moisture contents. An independent test of the module showed poor results, because fine tuning of Harvest machinery has an overriding effect. Secondly, the variation in weather conditions during autumn in Wageningen over a period of 38 years was analysed. The ranges of future root and sugar production appeared to be so wide that early predictions of the day on which the sugar quota are exceeded will not be very reliable. Thirdly, risks of severe frost or heavy rainfall in autumn were assessed, based on the same 38 year data set. The risk of frost damage to unHarvested beets proved to be negligible when the crop was Harvested before November 10, as advised by the sugar industry. The work described in this study makes the model PIEteR (a field specific bio-economic production model for sugar beet, developed for decision support at field and farm level) more applicable by using its potential to analyse the effects of different years and quota options.
