Impact of Sulfur Dioxide and Dimethyl Dicarbonate Treatment on the Quality of White Wines: A Scientific Evaluation

The biochemistry and physiology of raw material, the metabolism of microorganisms, and the methods used for processing and storage can affect the stability of wines. Due to the antimicrobial action of sulfur dioxide and dimethyl dicarbonate, the aim of this study is to determine the optimal treatment protocol to maintain the physico–chemical and microbiological stability of white wines with high residual sugar. Thus, the present research focuses on analyzing the influence of both treatments, combined or separate, on 45 wine samples obtained from a blend of Muscat Ottonel and Fetească Regală grape varieties, where different doses of 6% aqueous SO₂ solution (40, 80, and 160 mg/L) and dimethyl bicarbonate (0, 100, and 200 mg/L) were used. In order to assess the ability of dimethyl dicarbonate to suppress microorganisms, varying concentrations of <i>Brettanomyces bruxellensis</i> and <i>Schizosaccharomyces pombe</i> yeasts were inoculated (0, 30, 100 CFU/mL wine). The results indicate that, while sulfur dioxide cannot be entirely substituted in wines, both treatments can effectively lower or inhibit the activity of spoilage microorganisms. For the wines’ physico–chemical and microbiological stability, the treatment that used the synergistic force of sulfur dioxide (160 mg/L) and dimethyl dicarbonate (200 mg/L wine) performed the best.