Vineyard’s ozone application to induce secondary metabolites accumulation in grapes and wine

Abstract

In viticulture sector to find new tools for pest management has become an urgent necessity. Hence, grapevines cultivation has high production rate demand and to meet the intensive market request, a massive use of pesticides is often required. In addition to the environmental problems associated with large use of chemicals, there is an increasing number of consumers which are asking for safer, healthier and residue free foods and beverages. Recently, the use of ozone has been proposed as a possible alternative to traditional chemicals. However, studies on ozone application in the vineyard are very few especially considering its effect on grapes and wine quality and composition. In plant tissue ozone induce an oxidative stress which can triggers antioxidant response, and, therefore, it may enhance the production of antioxidant and stress-related secondary metabolites. As such, ozone can be considered an abiotic elicitor. In this study, canopies of Vitis vinifera (cv Sangiovese) plants have been sprayed with ozonated water throughout the vegetative growth and its effect on phenolic, antioxidant and aromatic compounds of grapes and wine have been assessed. In grapes, ozonated water induced a significant increase of antioxidant activity and total polyphenol content. Remarkably, changes in phenolic and aromatic profile in the resulting wine have also been observed. Specifically, Kampferol and Quercitin glucosides increased after ozone exposition as well as volatiles derived from the LOX-HPL pathway. These changes suggest that the oxidative stress induced leads to antioxidant metabolic response in grapes and therefore affects grapes and wine quality and composition.