Early detection project – make a GTD infection visible without disease symptoms

Kalecik Karası is a domestic grape variety of Turkey, originating from Kalecik district, 80 km from Ankara. Although there is no definite evidence, it is known that it was used in wine production by many civilizations that lived in the Anatolian region, especially the Hittites. Compared to other black wine grapes, it stands out with its low tannin content, rich fruity aroma and complex structure. In good vintages, red fruits such as strawberries, cherries and raspberries stand out in the aroma profile. Although its structure is elegant, it has the potential to age and develop similar to the ‘Pinot Noir’ wine of the Burgundy region. This offers a complex aroma structure including red flowers, earth and ripe fruits.

Wine is an intrinsically complex aromatic product. To formalize this aromatic diversity and the hierarchical structure of the aromas, it is common to present them in the form of a wheel of aromas. These are used for learning and communication purposes but never for the acquisition of sensory characteristics.

Viticulture has spread to unexpected locations, such as high-altitude terrain. Among these, high-altitude viticulture has captured considerable attention, not only for the uniqueness of its products and landscapes but also because it offers an effective response to climate changes
The aim of this study is to analyse and compare wineries that used Piwi varieties (acronym for the German Pilzwiderstandfähig, i.e., cryptogame-resistant) at high altitudes (between 500 and 920 m a.s.l.) with the traditional non-mountainous viticulture model.

Grape quality potential for wine production is strongly influenced by environmental parameters and agronomic factors. Several studies underline the rootstock effect on scions vegetative growth and berry composition [1] with an impact on wine quality. Rootstocks are promising agronomic tools for climate change adaptation and in most grape-growing regions the potential diversity of rootstocks is not fully used and only a few genotypes are planted. Moreover, little is known about the effect of rootstock genetic variability on the aromatic composition in wines.

The gustatory balance of dry wines is centered on three flavors, sourness, bitterness and sweetness. Even if certain compounds were already identified as contributing to sweetness, some taste modifications remain largely unexplained1,2. Some empirical observations combined with sensory analyzes have shown that an increase of wine sweetness occurs during post-fermentation maceration³. This step is a key stage of red winemaking during which the juice is left in contact with the marc, that contains the solid parts of the grape (seeds, skins and sometimes stems). This work aimed to identify a new taste-active compound that contributes to this gain of sweetness.