Integrated enzymatic–yeast biostrategy to obtain reduced-alcohol wine

Overripening of grapes, due to global warming, can result in unbalanced wines with higher alcohol content, lower acidity and an altered sensory profile. Pre-fermentative treatment of the must with a glucose oxidase-catalase enzyme system immobilized in silica‑calcium-alginate hydrogel capsules degraded up to 17.3% of the glucose in the must in 48 h to obtain wines with 1.0–1.3% vol ( v /v) lower alcoholic strength. Most of the gluconic acid produced by glucose oxidation was retained in the capsules, resulting in a mild reduction in the pH, thereby avoiding a strong acidification of the must. The remainder of the gluconic acid present in the must was largely degraded during the fermentation process using a selected strain of the yeast Schizosaccharomyces pombe (S. pombe) . Both the enzymatic treatment of the must with the capsules and the use of S. pombe , either in unique inoculation or in sequential inoculation with a Saccharomyces cerevisiae (S. cerevisiae) , led to balanced wines with a unique chemical profile. The combination of these two strategies, pre-fermentative and fermentative, presents an innovative and promising approach, not investigated so far, to counteracting the adverse effects of rising temperatures due to global warming.