Virgin pomace, or the dried residue from the crushed olives, still contains a minimal quantity of oil. To extract it, the pomace goes to extraction plants where it undergoes a preliminary drying process.
First, the dried pomace is mixed with hexane, a solvent that facilitates the dissolution of all remaining oil and the separation of the solids from the liquid portion, called hexanol.
The hexanol is then distilled to separate the solvent and obtain the crude pomace oil, which is characterized by a naturally high acidity, unpleasant taste and the presence of all the oxidized substances that formed during the period of storage of the pomace. To become edible it must undergo a refining process to obtain refined olive pomace oil.
QUALITY AND PURITY OF OILS
With EEC Regulation 2568 of 1991, the European Community defined the quality and purity characteristics that every olive and pomace oil must have, regulating analysis methods for all countries and setting the values of the parameters used to identify olive oil and its product categories.
Over the years several changes have been made, particularly Regulation 61/2011, which for the first time introduced the application of a sensory method to the assessment of oils, the Panel Test.