Volatile Compounds and Phenolic Composition of Virgin Olive Oil: Optimization of Temperature and Time of Exposure of Olive Pastes to Air Contact during the Mechanical Extraction Process

Abstract
The operative conditions of malaxation such as temperature and time of exposure of olive pastes to air contact (TEOPAC) affect volatile and phenolic composition of virgin olive oil (VOO) and, as a consequence, its sensory and healthy qualities. In this paper, optimal temperature and TEOPAC during malaxation were studied, in lab scale, in two Italian cultivars using phenolic compounds, volatile composition, and sensory analysis of VOO as markers. The optimal temperature and TEOPAC, selected by response surface modeling,were cultivar-dependent being 30 min of TEOPAC at the lowest temperature investigated (22 °C) and 0 min of TEOPAC at 26 °C for Frantoio and Moraiolo cultivars, respectively. Keywords: Virgin olive oil quality; oil mechanical extraction process; phenols; volatile compounds