Integrated use of ozonized water for a better management of sulphites in winery

Sulfur dioxide and sulphites in general are among the most common environmental pollutants and preservatives used in the food industry. The negative effects of sulphites on human health have been extensively documented. In  cellar, sulphites are added to the must before starting alcoholic fermentation and at the end of fermentation to block the activity of harmful microorganisms and to protect wine from oxidation. In the first case it is important to add sulfur dioxide as soon as possible, in order to avoid the development of spoilage yeasts present on the grape bunch which can attribute unpleasant organoleptic characters to the wine. Many less toxic molecules have been tested with the aim of replacing sulphites during finification, but to date no equally effective solution has been obtained.
In the industrial winemaking, the pathogenic microorganisms responsible for the deterioration of the fruit must be avoided to reach high grape quality. This is accomplished through the use of pesticides. These molecules are toxic to humans both through inhalation and through the consumption of wine. They are able to alter the soil ecosystem and contaminate water springs. Therefore their use should be reduced, if not avoided. An harmless and sustainable alternative to pesticides is represented by the use of antagonistic microorganisms, the bio-control agents, which are able to compete with pathogens and therefore to defeat them.The yeasts used in the project as bio-control agents have been isolated by the Research Group of the University of Padua from grape bunches collected in vineyards in the Veneto region and therefore are part of the microbial community that characterizes local wine production.