Olive cake is a by-product of the second extraction of olive oil. First extraction is done in the olive oil factories by mechanical squeezing of the olives. As a result of it, so called virgin olive oil is received. Remaining brown mass, called pomace, has a moisture of about 60% and oil content of about 7-8%. After the first extraction of olive oil, pomace is then transported to specialized factories, where the second extraction of oil by hexane is completed. As a result of this process, the second extraction oil is produced and the residue consisting of olive meat, olive skin, whole and crushed olive stones with the moisture of around 13-14% is received. This material is called olive cake and it is a biofuel.
Olive cake pellets. Olive cake with an approximately 12% moisture content is suitable for pelletizing. It can be pelletized without any further treatment, no adhesive is added. They are used in order to decrease the dust formation during the loading, unloading and handling of olive cake
Olive stones are a product of separation of the olive cake. Usually this is done by centrifugation or by putting olive cake into the water. In both cases olive stones are separated from the olive meat, olive skin and are used as a separate product.
If the centrifugation process is used, then so called “dark” olive stones are received, as it is more difficult to make a separation by centrifuges and some olive skin and olive meat will be present. Ash content of olive stones in this case will be on the level of 3-4%.
If the underwater method with later drying process is used, so called “pale” olive stones can be produced. Quantity of produced olive stones is significantly lower than olive cake volumes.You can find more information regarding olive residue products on our partners webpage.