Lopez Pinar Angela, Rauhut Doris, Ruehl Ernst, Buettner Andrea
Department of Chemistry and Pharmacy, Emil Fischer Center, Friedrich-Alexander-Universität Erlangen-Nürnberg Erlangen, Germany.
Department of Microbiology and Biochemistry, Hochschule Geisenheim University Geisenheim, Germany.
Front Chem. 2017 Mar 28;5:20. doi: 10.3389/fchem.2017.00020. eCollection 2017.
This study aimed to characterize the effects of bunch rot and powdery mildew on the primary quality parameter of wine, the aroma. The influence of these fungal diseases was studied by comparative Aroma Extract Dilution Analyses (AEDA) and sensory tests. The effect of bunch rot was investigated on three grape varieties, namely White Riesling, Red Riesling and Gewürztraminer and that of powdery mildew on the hybrid Gm 8622-3; thereby, samples were selected that showed pronounced cases of infection to elaborate potential currently unknown effects. Both infections revealed aromatic differences induced by these fungi. The sensory changes were not associated with one specific compound only, but were due to quantitative variations of diverse substances. Bunch rot predominantly induced an increase in the intensities of and aroma notes. These effects were found to be related to variations in aroma substance composition as monitored via AEDA, mainly an increase in the FD factors of lactones and a general moderate increase of esters and alcohols. On the other hand, powdery mildew decreased the character of the wine while the remaining sensory attributes were rather unaffected. Correspondingly, FD factors of the main aroma constituents were either the same or only slightly modified by this disease. Moreover, bunch rot influenced the aroma profiles of the three varieties studied to a different degree. In hedonic evaluation, bunch rot-affected samples were rated as being more pleasant in comparison to their healthy controls in all three varieties while the powdery mildew-affected sample was rated as being less pleasant than its healthy control.
本研究旨在表征灰霉病和白粉病对葡萄酒主要品质参数——香气的影响。通过比较香气提取物稀释分析（AEDA）和感官测试研究了这些真菌病害的影响。研究了灰霉病对三个葡萄品种，即白雷司令、红雷司令和琼瑶浆的影响，以及白粉病对杂交品种Gm 8622 - 3的影响；因此，选择了表现出明显感染情况的样本，以阐述目前未知的潜在影响。两种感染均揭示了这些真菌引起的香气差异。感官变化并非仅与一种特定化合物相关，而是由于多种物质的定量变化所致。灰霉病主要导致果香和花香香气强度增加。通过AEDA监测发现，这些影响与香气物质组成的变化有关，主要是内酯类物质的风味稀释（FD）因子增加，以及酯类和醇类物质普遍适度增加。另一方面，白粉病降低了葡萄酒的果香特征，而其余感官属性受影响较小。相应地，这种病害对主要香气成分的FD因子要么没有影响，要么影响很小。此外，灰霉病对所研究的三个品种的香气特征影响程度不同。在享乐评价中，与健康对照相比，所有三个品种中受灰霉病影响的样本被评为更令人愉悦，而受白粉病影响的样本被评为不如其健康对照令人愉悦。
