Quality selection is the most time-consuming bottleneck in grapevine breeding. Wines of promising grapevine breeding material have to be evaluated for several years to prove their suitability for quality wine production. The investigation of must and wine compounds with analytical and sensorial techniques is suitable for wine quality description. This knowledge can be used to develop environmentally independent molecular markers to predict genetic quality potential of grapevines and thus increase breeding efficiency.
It is well known that wine quality depends largely on the genotype of a grapevine cultivar. New innovative grapevine cultivars are demanded to produce grapes that are suitable for the production of wines with high quality. Additionally, they need to be resistant against the major grapevine pathogens, especially the mildews. Growing such new resistant cultivars will pave the way for a more ecologically and economically sustainable viticulture.
Most resistances have their origin in American and Asian wild grapevine species and were introgressed into the breeding material. Often, additional negative properties (e.g. poor taste, off-flavors) were also passed to their descendants. Development of appropriate tools to eliminate such negative properties in early breeding steps and to promote positive quality characteristics are our main research objectives.
At the Institute for Grapevine Breeding, we identify genomic regions which have significant influence on wine quality. We develop genetic fingerprints as a powerful tool for the prediction of wine quality potential at an early stage. As a consequence promising vines can be selected at the very beginning of growth and unsuitable seedlings can be removed early from the breeding program. This will enable the evaluation of wine quality years before vines bear grapes and increase breeding efficiency enormously. The improved selection processes on genome scale will focus on the most relevant vines and shorten the quality testing by years.
For quality assessment of new varieties, must and wine constituents are analyzed at our accredited wine laboratory, which is equipped with modern instruments like FTIR spectroscopy, gas chromatography coupled to mass spectrometry and olfactometry, liquid chromatography and atomic absorption spectroscopy.
Our own experimental wine cellar is specialized in micro-vinification: small scale wine production of new single vines in volumes of 0.5 to 5 liters. The winemaking process follows a standardized protocol. Thanks to a stringently monitored fermentation process we get highly comparable wine samples for sensory evaluation. Taking into account the analytical data it turns out which vines have the potential to become new varieties for a sustainable viticulture.