Contribution for the characterization of olive oils of the Douro region (Portugal)

Abstract

The "Douro Demarcated Region" in Portugal was the first demarcated and regulated wine region in the world, where the famous "Port Wine" is produced. In this region, ancient olive groves can be found in Douro hills and valleys, usually in small scattered plots, often abandoned, or above the vineyards in the slopes, benefiting from the region's climate. In recent years, olive oil production in Douro region has become an important source of income for Port wine companies, being considered one of the most precious food products of the region. In this sense, the present work aimed to characterize the physicochemical and sensorial attributes of the olive oils produced in the Douro region, namely free acidity, peroxide index, K232 and K270 specific extinction coefficients, fatty acids composition, tocopherols contents and sensory attributes of olive oils produced in two consecutive years (2014 and 2015). The physicochemical parameters and the sensory evaluation show that the olive oils produced in Douro region are of excellent quality. At the sensory level, these olive oils are characterized by fresh notes of rosemary/lavender, pine and eucalyptus, as well as green almonds. Regarding the fatty acids composition, the monounsaturated average content was around 76% in both years under study. Also, for the year 2014, a high tocopherol content was found, greater than 500 mg/kg.