Technical Feasibility of Glucose Oxidase as a Prefermentation Treatment for Lowering the Alcoholic Degree of Red Wine

Abstract

In the present work, the use of the enzymatic system glucose oxidase/catalase was evaluated as an alternative to decrease the glucose concentration and eventually produce a reduced alcohol wine. The effects of glucose oxidase, catalase and aeration on the glucose concentration were evaluated after 24 and 48 h of treatment of 27 °Brix Carmenere must. The results showed that the effect of aeration and glucose oxidase was not significant compared to the effect produced by glucose oxidase itself. In addition, the use of catalase combined with glucose oxidase provided the best result, decreasing the glucose concentration by 51% and 78% after 24 and 48 h, respectively, when 200 U/ml of both enzymes was used. The alcoholic degree obtained after 3 and 5 days under this treatment and subsequent fermentations were 15 ° ± 0.8 and 14 ° ± 0.8, respectively. A major drawback was obtained due to the color change of Carmenere must because of the H2O2 that was produced during the glucose oxidase treatment, despite the presence of catalase. The technical feasibility of using this pre-fermentative process led to a divided conclusion. It was possible to obtain a lower alcoholic degree using the glucose oxidase/catalase system, but if the goal is the industrial application of this technique, the color change must be investigated further. An evaluation of the glucose oxidase/catalase ratio was projected to show an improvement of the H2O2 elimination and subsequently decrease the effect on color change.