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WINEGROWING determine the future wine style in terms of aroma from the fruit itself. The Department of Viticulture & Oenology (Stellenbosch University, South Africa) and the National Wine and Grape Industry Centre (Australia) are leading an ambitious project to study the berry aromatic sequence during fruit maturation in relation to wine flavor profiles. The scientific aim is to better understand fruit growth and composition (fruit quality) and to develop practical tools and methods to predict or predetermine wine style in terms of aromatic characteristics. Berry ripening, wine flavors and the elaboration of low-alcohol wines are among the priorities of the worldwide wine industry today, mainly in the context of climate change (increase of temperature and evapotranspiration) and water scarcity. The research program (financed by Wine Industry Network for Expertise and Technology and Distell) has allowed the transfer of two methods to the wine industry, for red and white cultivars respectively, to predict harvest date and the associated wine style. The research in Australia is starting at NWGIC (Charles Sturt University). 66 p racti c al w i ne ry & v i ne yard APRIL 20 13 Berry hue thresholds (in degree) Expected wine aromatic profiles > 90 Green/unripe 90 – 85 Green/asparagus 85 – 80 Asparagus/citrus 80 – 75 Asparagus/tropical fruit/ grapefruit/citrus 75 – 70 Tropical fruit 70 – 65 Fermentative/terpene 65 – 60 Phenolic/neutral/terpene Table 1: Thresholds of berry hue (in degree), according to the HSL model of color representation and expected style of wine for most white cultivars. Simplified thresholds (berry color evolution occurs irrespectively of Brix and titratable acidity to a certain extent). How to predict harvest date The method for red cultivars uses the concept of berry sugar loading and the method for the white cultivars uses the berry color evolution (Deloire, Wineland, January 2011). Both methods are based on the fact that the berry aromatic sequence seems to be preprogrammed from véraison onward, and therefore it can be predicted. The berry aromatic sequence could be explained as follows: Red cultivars—When sugar per berry reaches a plateau (or slows down), there are four stages that progress in sequence, Stage 1: Fresh fruit/green plant-like aroma/unripe plum; Stage 2: Neutral/spicy like aroma or pre-ripe (mature berry aromas); Stage 3: Mature berry aromas such as black currant, raspberry, cherry; Stage 4: Over-ripe aromas such as dried fruit, prune (See Figure 1).