Foliar Spray Application of Inactive Dry Yeast at Veraison: Effect on Berry Skin Thickness, Aroma, and Phenolic Quality

Achieving a satisfactory aroma and phenolic maturity at harvest is key for producing quality wines. A foliar spraying treatment with yeast derivatives was tested on the grape (Vitisi vinifera L.) varieties Chardonnay, Cortse, Nebbiolo, and Barbera. The treatment was carried out at version with two different formulation to enhance aroma and phenolic quality. The influence of the treatment on berry skin thickness was also evaluated. The analyses were carried out on grapes at harvest and experimental wines were produced and analyzed. The berry distribution evidenced smoother ripening of treated berries and resulted in increases in must acidity with affecting sugar accumulation. Further, berry thickness also increased in treated berries, in Barbera especially. Overall, the treatment influenced the grape quality, providing a tool to winemakers for differentiation of the products.