Red wines are usually matured in wooden barrels to improve sensory characteristics. An alternative process can be microoxygenation and/or the addition of oak chips. The objective of the Master's thesis was to determine the optimal conditions for microoxygenation and the addition of oak chips to the development of phenolic compounds, aromatic profile and color stabilization of Refosco wine. The practical part of the experiment consisted of maturing the wine in four stainless steel tanks with different oxygen concentration and the addition of oak chips. The phenolic characteristics of the wine were determined by analyzes of total phenolics, non-tannins, total anthocyanins, non-flavonoids, proanthocyanidins, vanillin index, mean degree of polymerization and percentage of prodelphinidins and galloylation. The color characteristics of the wine were determined by analysing the color density, color hue, percentage of red color in the form of flavylium cation, estimation of SO2 content, percentage of red pigment, degree of red pigment coloration at different wavelengths (420 nm, 520 nm and 620 nm) and turbidity. At the end of the practical part, we performed a sensory analysis of the wine samples using the method RATA and the ranking method with a commission of trained experts. During maturation of the wine, the concentration of total phenols and total anthocyanins decreased in all wine samples. The improvement of the phenolic and color characteristics of the wine was mainly influenced by the addition of oak chips and the combination of the highest concentration of added oxygen with the addition of oak chips. Sensory analysis showed that the wine sample microoxygenated with the highest concentration of oxygen and the added oak chips received the best overall score.
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