Experiments with oenological methods to increase the spicy aroma in Austrian Grüner Veltliner wines

Abstract

Grüner Veltliner is Austria's most important grape variety, accounting for 32.5% of the vineyard area (a total of around 14,500 ha). There is a noticeable trend with this variety away from fresh, fruity wines towards more spicy, single-vineyard wines. This is especially true for export-oriented producers. The aim of this scientific study is to test oenological methods for increasing the leading substance of the spicy aroma, the sesquiterpene rotundone and to sensory evaluate the wines. The methods skin contact, full and partial fermentation on the skins, addition of whole grapes and or leaves were tested in two independent experimental designs. The wines were analysed using a SPE-SPME-GC-TQMS method. The "retro-tratitional methods" of winemaking mentioned in the article can enhance the spiciness of the wines to a certain degree. Especially the addition of whole grapes as well as partial maceration gave the best results here. The increase in spiciness was observed both sensorially and analytically, as evidenced by higher rotundone contents. However, in summary, it must be stated that the results indicate that an exclusive analysis of rotundone, without the inclusion of phenols and other volatile substances, cannot contribute to a full understanding of the matter, which is based on the interaction of many components. Further analysis both sensory and analytical involving many volatile compounds and phenols are therefore absolutely necessary.