Has anyone tried extraction using SFE (Super critical Extraction)? It is a method by which liquefied Carbon Dioxide is passed through the olive mash. It is less expensive and does not contain the organic solvents. It currently used for decaffeinating coffee. The CO2 acts like a strong organic solvent.
Supercritical extraction has been used for years for lab analysis and for extraction of essential oils and is now being used for larger scale processes. We don't know if anybody is doing that here in the US. Most of the olive oil produced here is not refined. Getting the majority of the oil out of olive paste is quick and economical with a centrifuge. Getting the last remaining oil out of the pomace is where the CO2 would be used.
Pilot plants for removing squalene from olive waste have been designed using supercritical CO2. Squalene is then hydrogenated to squalane for sale to the health food and pharmaceutical industries.
I don't know about expense but it would have the cachet of avoiding petrochemical residues and might even warrant organic certification. It of course would still not be considered extra virgin.
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