Effect of some winemaking factors on rotundone levels of Pelaverga di Verduno wines

Pelaverga di Verduno Protected Designation of Origin is a red wine obtained from Pelaverga piccolo , an autochthonous grape variety grown in Piedmont. This wine is characterized by a light colour and a unique, intense spicy aroma. The analysis of this wine detected a significant concentration of rotundone (approximately 40 ng L −1 ), which is known to impart a distinctive pepper note and has a very low olfactory threshold (16 ng L −1 in wine). The measured concentrations, well above the perception threshold, could link rotundone directly to the spicy notes highlighted by the sensorial analysis of Pelaverga wines. The impact of certain oenological factors on the concentration of this compound in wine was therefore assessed, showing that moderate amounts of oxygen could lead to a significant increase in the concentration of rotundone in finished wines. Conversely, different doses of sulfur dioxide or storage temperature of the wines had no effect on this compound.