Olive oil production sector plays an important role in Portuguese economy. It had a major growth over the last decade, increasing its weight in the overall national exports. International market is increasingly more demanding for Mediterranean traditional products, especially in the Northern European markets, where consumers are looking for more sustainable products. Trying to support this growing demand this study addresses olive oil production under the environmental and eco-efficiency perspectives. The analysis considers two consecutive product life cycle stages: olive trees farming; and olive oil extraction in mills. Addressing olive farming, data collection covered two different organizations: a middle-size farm (~12 ha) (F1) and a large-size farm (~100 ha) (F2). Results from both farms show that olive collection activities are responsible for the largest amounts of Green House Gases (GHG) emissions. In this activities, estimate for the Carbon Footprint per olive was higher in F2 (188 gCO2eq./kg olive) than in F1 (148 gCO2eq./kg olive). Considering olive oil extraction, two different mills were considered: one using a two phases system (2P) and other with a three phases system (3P). Results from the study of two mills show that there is a much higher use of water in 3P. Energy intensity (EI) is similar in both mills. When evaluating the GHG generated, two conditions are evaluated: a biomass neutral condition resulting on a carbon footprint per liter of olive oil higher in 2P (273 gCO2eq./L olive oil) than in 3P (184 gCO2eq./L olive oil); and a non-neutral biomass condition in which 2P reduces its carbon footprint to 92 gCO2eq./L olive oil. When addressing the carbon footprint of possible combinations among studied subsystems, results suggest that olive harvesting is the major source for GHG.
