Šuklje Katja, Antalick Guillaume, Buica Astrid, Langlois Jennifer, Coetzee Zelmari A, Gouot Julia, Schmidtke Leigh M, Deloire Alain
Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, P.O. Box X1, Matieland, Stellenbosch 7602, South Africa.
Department of Viticulture and Oenology, Stellenbosch University, P.O. Box X1, Matieland, Stellenbosch 7602, South Africa.
J Sci Food Agric. 2016 Feb;96(3):915-26. doi: 10.1002/jsfa.7165. Epub 2015 Apr 10.
The aim of this study, performed on Sauvignon blanc clones SB11 and SB316, grafted on the same rootstock 101-14 Mgt (Vitis riparia × V. ruperstris) and grown at two adjacent vineyards, was two-fold: (1) to study wine chemical and sensory composition of both clones within an unaltered canopy; and (2) to determine the effect of defoliation (e.g. bunch microclimate) on wine chemical and sensory composition.
Orthogonal projection to latent structures discriminate analysis (OPLS-DA) was applied to the concentration profiles of volatile compounds derived from gas chromatography-mass spectrometry data. The loadings directions inferred that 3-isobutyl-2-methoxypyrazine (IBMP) discriminated control treatments (shaded fruit zone) of both clones from defoliation treatments (exposed fruit zone), whereas 3-sulfanyl-hexan-1-ol (3SH), 3-sulfanylhexyl acetate (3SHA), hexanol, hexyl hexanoate and some other esters discriminated defoliated treatments from the controls. The OPLS-DA indicated the importance of IBMP, higher alcohol acetates and phenylethyl esters, for discrimination of clone SB11 from clone SB316 irrespective of the treatment. Defoliation in the fruit zone significantly decreased perceived greenness in clone SB11 and elevated fruitier aromas, whereas in clone SB316 the effect of defoliation on wine sensory perception was less noticeable regardless the decrease in IBMP concentrations.
These findings highlight the importance of clone selection and bunch microclimate to diversify produced wine styles.
本研究以长相思品种SB11和SB316克隆植株为材料，嫁接到同一砧木101-14 Mgt（河岸葡萄×沙地葡萄）上，种植于两个相邻葡萄园，目的有两个：（1）研究在未改变树冠情况下两个克隆植株葡萄酒的化学和感官成分；（2）确定去叶处理（如穗部小气候）对葡萄酒化学和感官成分的影响。
将正交投影到潜在结构判别分析（OPLS-DA）应用于气相色谱-质谱数据得出的挥发性化合物浓度图谱。载荷方向表明，3-异丁基-2-甲氧基吡嗪（IBMP）可区分两个克隆植株的对照处理（果实遮荫区）和去叶处理（果实暴露区），而3-巯基己醇（3SH）、3-巯基己基乙酸酯（3SHA）、己醇、己酸己酯和其他一些酯类可区分去叶处理和对照处理。OPLS-DA表明，无论处理如何，IBMP、高级醇乙酸酯和苯乙酯对于区分克隆SB11和克隆SB316都很重要。果实区去叶显著降低了克隆SB11的感知生青味并提升了果香，而在克隆SB316中，尽管IBMP浓度降低，但去叶对葡萄酒感官感知的影响不太明显。
这些发现突出了克隆选择和穗部小气候对于使所产葡萄酒风格多样化的重要性。
