Influence of partial dealcoholization by reverse osmosis on red wine composition and sensory characteristics

Two red wines with a very high ethanol content were partially dealcoholized by reverse osmosis, so that the influence of this technique on wine color, chemical composition and sensory quality could be studied. No statistically significant differences were found in pH, color intensity, total phenolic index, proanthocyanidin concentration and their mean degree of polymerization between control wines and partially dealcoholized wines (−1 and −2 vol. %). Some slight but significant differences were found in titratable acidity, anthocyanins, CIELab coordinates and polysaccharides. However, these differences were really quite small and only significant in a few cases. Moreover, a trained panel of tasters had severe difficulty in distinguishing between control and partially dealcoholized wines in triangular tests, and results were statistically significant only in some of the comparisons. It is concluded that this technique can be very useful for the partial dealcoholization of red wines because they hardly alter their composition and sensory characteristics.