The volatile composition of grapes has a direct impact on the final aromatic composition of wine and plays a crucial role in determining its quality. Various factors, such as agronomic practices, climatic conditions or grape variety, can influence the volatile composition of grape juices. This study aimed to determine the influence of three doses of urea, applied at two different phenological stages (pre-veraison and veraison), on the volatile composition of Tempranillo musts, during two consecutive seasons. The urea application did not have an impact on the yield of the vineyard or the general parameters of the Tempranillo must. However, the three different concentrations of urea modified the volatile composition. Specifically, the higher concentration of urea improved the terpenoids, C13 norisoprenoids, and benzenoid compounds in grape juice. Additionally, when urea treatments were applied at pre-veraison, terpenoids, C13 norisoprenoids, esters, and benzenoid compounds were improved in Tempranillo must. However, the weather was an important factor influencing the volatile compounds in Tempranillo musts. Consequently, foliar applications of urea could be an interesting viticulture practice in order to enhance the volatile compounds in Tempranillo musts.
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