SO2 in wines: rational use and possible alternatives

Sulfur dioxide (SO2) is the most widely used preservative additive in winemaking and conservation due to its antimicrobial and antioxidant properties. Possible allergenic effects of sulfites and consumer demand for “wine naturalness” have stimulated the interest of producers and researchers to rationalize the use of SO2. Most Saccharomyces yeasts produce modest amounts of sulfites; therefore, the production of totally sulfite-free wines is a difficult task. The greatest efforts were devoted to limit compounds that permanently bind SO2, to increase the share of its molecular form (pH management), and to research new preserving technologies or replacement substances of natural origin.