Bowen Amy J, Reynolds Andrew G
Cool Climate Oenology and Viticulture Institute (CCOVI), Brock University, St. Catharines, ON L2S 3A1, Canada.
Cool Climate Oenology and Viticulture Institute (CCOVI), Brock University, St. Catharines, ON L2S 3A1, Canada.
Food Res Int. 2015 Oct;76(Pt 3):540-549. doi: 10.1016/j.foodres.2015.06.046. Epub 2015 Jul 8.
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.
冰酒是一种甜型餐后葡萄酒，由压榨自然冻结在葡萄藤上的葡萄制成。由于气候事件，冰酒葡萄经历的冻融循环可能会改变其化学和感官特征。我们的目标是确定收获日期对冰酒原酒及葡萄酒基本化学变量和香气化合物的影响。雷司令（Riesling）和维代尔（Vidal）冰酒由2004年12月至2005年2月期间采摘的葡萄制成；收获1（H1）：12月19日；收获2：12月29日；收获3（H3）：1月18日；收获4（H4）：2月11日（仅维代尔）。冰酒原酒的可滴定酸度和pH值存在差异（仅维代尔）。所有葡萄酒基本化学分析物在不同收获日期均有差异。维代尔和雷司令葡萄酒中的所有香气化合物均有差异。大多数香气化合物的最高浓度出现在最后一个收获日期；维代尔的24种中有16种，雷司令的23种中有17种。最晚收获日期的异丁酸乙酯、3 - 甲基丁酸乙酯、1 - 己醇、1 - 辛烯 - 3 - 醇、1 - 辛醇、顺式玫瑰氧化物、氧化橙花叔醇、苯甲酸乙酯、苯乙酸乙酯、γ - 壬内酯和β - 大马酮含量最高。H1的丁酸乙酯、己酸乙酯、芳樟醇、4 - 乙烯基愈创木酚和辛酸乙酯含量最高。基于气味活性值，在不同收获日期，气味最强的化合物是β - 大马酮、顺式玫瑰氧化物、1 - 辛烯 - 3 - 醇、辛酸乙酯、己酸乙酯和4 - 乙烯基愈创木酚。主成分分析发现，除4 - 乙烯基愈创木酚与H1相关外，大多数香气化合物与最后一个收获日期相关。对于挥发性化合物，使用典型变量分析时，收获日期被视为一个区分维度。
