Herein the improvement of liquefied cork for the production of a bio-oil, which can be faced as a potential bio-fuel, is presented. Cork liquefied products were therefore subjected to water extraction to separate the most polar compounds, in particularly, those arising from cellulose and hemicellulose hydrolysis. After drying the organic extract, the higher heating value (HHV) was estimated. The results clearly revealed that the extraction process led to a bio-oil with an upgraded HHV indicating, thus, this refined product is more likely to be used as a biofuel for hot steam furnaces, for example, than the liquefied cork or even cork in its primitive form. (c) 2016 Elsevier Ltd. All rights reserved.