Sensory Quality Control of Young vs. Aged Sweet Wines Obtained by the Techniques of Both Postharvest Natural Grape Dehydration and Fortification with Spirits During Vinification

Although grapes subjected to different sugar concentration methods are known to provide also different types of sweet wines, the exact influence of such methods on the sensory properties of the wines is largely unknown. The purpose of this work was to identify differences in sensory profile between young and aged wines obtained from grapes subjected to various sugar concentration techniques. Differences in sensory properties were judged by a panel of trained tasters. Young sweet wines were judged to have a sweeter balance and a dried fruit taste associated to higher global sensory attributes of odour and taste. Some differences in sensory fingerprint were due to their aging in oak barrels, which introduced flavour mainly based on attributes such as vanilla, phenolic, wood, and burnt wood tastes. There were also clear differences between sweet wines obtained by natural grape dehydration and others obtained by fortification with 96 % (v/v) ethanol fit for human consumption: naturally sweet wines were most appreciated than fortified sweet wines, since they were not only ranking higher in honey and dried fruit tastes, but also in overall colour and odour.