Creating an artificial wine taster: Inferring the influence of must and yeast from the aroma profile of wines using artificial intelligence

The human brain is able to compute information from very complex olfactorical impressions. The special pattern of the concentrations of hundreds of aroma constituents allows an experienced wine taster to determine special features of the wine, for instance grape variety or vintage.Artificial Neural Networks are often used to recognize shapes and patterns like faces or finger prints. Here we use Artificial Neural Networks to mimic the abilities of a wine taster to deal with very complex olfactorical patterns. We produced 120 unique wines combining twelve different grape musts and ten yeast strains and determined the aroma profile (83 aroma constituents) of all wines. We analyzed the ability of a well trained neural network to recognize the used must variety and the fermenting yeast strain from unknown aroma profiles. Furthermore we investigated the capability to predict the aroma profile of a wine with a must variety/yeast strain combination that is new to the neural network.In 96 % of all trials the neural network identified the must that was used for wine production correctly (expected random propability: 8 %). An accurate identification of the yeast strain, used for fermentation, occurred in 67 % of all trials (propability by chance: 10 %).The aroma profiles of the must/yeast combinations new to the neural network were forecasted with a divergence of only 2.1 % compared to the actual wine of this production characterization. Thus we conclude that a comprehensive description of wines using neural networks is possible.

Auswirkung verschiedener Bodenpflegesysteme auf rebenparasitäre und rehvirenübertragende Nematoden

Research NoteEffects of different types of soil cultivation to grape parasitical and grape virus vector nematodesWithin the research project "Soil management in selected locations around Lake Neusiedl" soil samples were taken from Donnerskirchen and Rust for the analysis of the nematode-pedofauna during summer 1999. At Rust (planted with cv. Blauburgunder) the type of soil management had a highly significant effect on the nematode population. After five years of soil covering with straw, permanent green cover or green cover in winter the nematode population on average was twice as high as in bare soil and green cover during spring. The latter variants were clean cultivated in spring. Distribution of nematodes in the sloping site of Donnerskirchen (planted with cvs Gruner Veltliner and Welschriesling) turned out to be inhomogenous, depending on the site of the slope. Here soil cultivation had no significant influence on the nematode fauna

Genetic variability and incidence of systemic diseases in wild vines (Vitis vinifera ssp. silvestris) along the Danube

In the riparian woods of Danube and March east of Vienna 87 wild specimens of Vitis vinifera ssp. silvestris were genetically analysed and compared. The silvestris population can be split into 6 distinct groups, but this clustering cannot be explained solely by the geographical distance. The unique genetic variability observed represents a strong case for preservation of wild grapevines.The incidence of bacterioses, viroses and nematodes transmitting nepoviruses to these vines were registered. None of the analysed specimens suffered from Agrobacterium vitis-induced crown gall. Only some vines were infected by viral pathogens such as GLRaV I and SLRV. Thus the wild vines do not constitute a risk for the surrounding commercial vineyards. On the other hand, diseases spread from cultivated grapevines may seriously harm the wild vine population. Four species of nematodes transmitting nepoviruses were registered. Samples of Xiphinema vuittenezi and Longidorus attenuatus from the Lobau (natural forests, north of the Danube in the area of Vienna) differ morphometrically from others found on arable soils or isolated from the research area.

Gruppenselektion: wenn Sozialparasiten trotz Selektionsvorteil den Kürzeren ziehen

Tiefenbrunner, A., Tiefenbrunner, M., Tiefenbrunner, W. (2011): Gruppenselektion: wenn Sozialparasiten trotz Selektionsvorteil den Kürzeren ziehen. Linzer biologische Beiträge 43 (1): 85-96, DOI: http://doi.org/10.5281/zenodo.452451

New Tools for Phylogenetic reconstruction using character state trees

Tiefenbrunner, A., Tiefenbrunner, M., Tiefenbrunner, W. (2011): New Tools for Phylogenetic reconstruction using character state trees. Linzer biologische Beiträge 43 (1): 97-114, DOI: 10.5281/zenodo.532568

Das Komplexauge als phasenmodulierende Fresnel Zonensphäre mit vielen optischen Achsen

Tiefenbrunner, W., Tiefenbrunner, M., Wahra, A., Tiefenbrunner, A. (2012): Das Komplexauge als phasenmodulierende Fresnel Zonensphäre mit vielen optischen Achsen. Linzer biologische Beiträge 44 (2): 1677-1696, DOI: http://doi.org/10.5281/zenodo.1010699

Abb. 2 in Das Komplexauge als phasenmodulierende Fresnel Zonensphäre mit vielen optischen Achsen

Abb. 2: Die Eckpunkte eines Musters aus gleichseitigen Dreiecken liegen auf den Zonen einer FZP und bilden die Zentren eines Musters aus gleichseitigen Sechsecken. Die Berechnung der Strecke az für z = 7, (m=1, n=2 nach Gl. 27 bzw. m=3, n=2 nach Gl. 26) Nähere Erläuterungen siehe Text.Published as part of <i>Tiefenbrunner, W., Tiefenbrunner, M., Wahra, A. & Tiefenbrunner, A., 2012, Das Komplexauge als phasenmodulierende Fresnel Zonensphäre mit vielen optischen Achsen, pp. 1677-1696 in Linzer biologische Beiträge 44 (2)</i> on page 1689, DOI: <a href="http://zenodo.org/record/10106997">10.5281/zenodo.10106997</a&gt

Abb. 3 in Das Komplexauge als phasenmodulierende Fresnel Zonensphäre mit vielen optischen Achsen

Abb. 3: Querschnitt durch eine Zonensphäre mit vielen optischen Achsen. Für eine davon wird gezeigt, wie eine zwischen den Löchern radial verlaufende Pigmentanordnung das Licht von achsenfernen Löchern abschirmt.Published as part of <i>Tiefenbrunner, W., Tiefenbrunner, M., Wahra, A. & Tiefenbrunner, A., 2012, Das Komplexauge als phasenmodulierende Fresnel Zonensphäre mit vielen optischen Achsen, pp. 1677-1696 in Linzer biologische Beiträge 44 (2)</i> on page 1691, DOI: <a href="http://zenodo.org/record/10106997">10.5281/zenodo.10106997</a&gt