Novel Endotherapy-Based Applications of Ozonated Water to Bobal Grapevines: Effect on Grape Quality

Abstract

Ozonated water has recently been incorporated in the management of grapevine diseases, which in turn can alter the fruit quality. When wood-inhabiting pathogens are involved, trunk injection or “endotherapy” represents a promising application method. Thus, the present study aimed to evaluate the effect on grape quality of ozonated water applied to Vitis vinifera L. cv. Bobal grapevines through endotherapy (E) or its combination with spraying (E + S). Grape quality at harvest was evaluated through several enological and chromatic parameters, the phenolic maturity, the varietal aroma potential index (IPAv) and the phenolic and volatile composition. The E treatment improved the chromatic characteristics and favored the accumulation of phenolic compounds. Conversely, E + S had a detrimental effect on the color and phenolic content and, although their synthesis was enhanced, the extractability of anthocyanins was negatively affected. In terms of aroma, both treatments reduced the content of glycosylated precursors but increased certain free volatiles. The application of ozonated water to grapevines, even when injected into the trunk, results in changes in fruit quality and a possible impact on wine attributes. Our findings and those in the literature support that, with the appropriate dose, frequency and method of application, ozonated water could be used with a twofold objective: disease management and grape quality improvement.