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 glucose oxidase/catalase enzymatic system was evaluated as an alternative to decrease glucose concentration and eventually produce a reduced-alcohol wine. The effects of glucose oxidase, catalase, and aeration on glucose concentration were evaluated after 24 and 48 hr of treatment of 27°Brix Carmenere must. The results showed that the effect of aeration and glucose oxidase was not significant compared with 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 hr, respectively, when 200 U/mL of both enzymes was used. The alcoholic degree obtained after three and five days under this treatment and subsequent fermentations were 15% (v/v) ± 0.8 and 14% (v/v) ± 0.8, respectively. A major drawback of this treatment was the color change of Carmenere must because H₂O₂ was produced during the glucose oxidase treatment, despite the presence of catalase. The technical feasibility of using this prefermentative process led to a divided conclusion; obtaining a lower alcoholic degree using the glucose oxidase/catalase system was possible, but if the goal is the industrial application of this technique, the color change should 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.