The use of sulfur dioxide (SO2) as wine additive is able to ensure both antioxidant protection and microbiological stability. In spite of these undeniable advantages, in the last two decades the presence of SO2 in wine has raised concerns about potential adverse clinical effects in sensitive individuals. The winemaking industry has followed the general trend towards the reduction of SO2 concentrations in food, by expressing at the same time the need for alternative control methods allowing reduction or even elimination of SO2. In the light of this, research has been strongly oriented toward the study of alternatives to the use of SO2 in wine. Most of the studies have focused on methods able to replace the antimicrobial activity of SO2. This review article gives a comprehensive overview of the current state‐of‐the‐art about the chemical additives and the innovative physical techniques that have been proposed for this purpose. After a focus on the chemistry and properties of SO2 in wine, as well as on wine spoilage and on the conventional methods used for the microbiological stabilization of wine, recent advances on alternative methods proposed to replace the antimicrobial activity of SO2 in winemaking are presented and discussed. Even though many of the alternatives to SO2 showed good efficacy, nowadays no other physical technique or additive can deliver the efficacy and broad spectrum of action as SO2 (both antioxidant and antimicrobial), therefore the alternative methods should be considered a complement to SO2 in low‐sulfite winemaking, rather than being seen as its substitutes.

Recently, the European Union regulation has fixed the maximum permitted dealcoholization level at 2 %; however in some cases, higher dealcoholization levels could be necessary. It is assumed that higher levels of dealcoholization could negatively affect the organoleptic quality of wine, but little data on this item is available. In the present study, two red wines (cv. Aglianico) with different initial alcohol contents (15.37 and 13.28 % v/v), were partially dealcoholized at three levels (-2, -3, -5 % v/v), by a polypropylene hollow fibre membrane contactor apparatus. In order to evaluate if dealcoholized wines differed from the untreated ones, triangle sensory tests were performed. Both -2 % wines were not perceived as different from the standard wines, while both -5 % wines were different. Sensory profiles and overall quality ranking were obtained by a selected and trained panel. Dealcoholization caused a modification of the sensory profiles, and the greatest differences were found after a dealcoholization of 5 % v/v. The most decreased olfactory notes were those of "Red fruits", "Cherry" and "Spicy", which is very important for the sensory quality of red wine. Concerning taste, both -5 % dealcoholized wines were more astringent than the correspondent untreated ones. Slighter differences were found for the other degrees of dealcoholization. The analysis of the volatile compounds, both free and glycoconjugated was performed by solid-phase extraction and gas chromatography mass spectrography analysis. While the composition of the glycoconjugated volatile fraction was almost not affected, many free compounds were decreased, most of all esters and alcohols, with an increasing amounts as the level of dealcoholization raised

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