Processing of vegetable oils by membrane technology

Abstract

From a historical perspective, the massive consumption of vegetable oils is a relativelyrecent phenomenon that began in the twentieth century due to the development oflarge-scale production of machinery and supplies after the consolidation of the indus-trial revolution It was 6,000 years ago that the use of olive oil in the Mediterraneanregion was registered, whereas the first record of sesame oil being used for humanconsumption was in India in 1137BC. Recent research shows that peanut oil was usedin America before European colonization and that palm oil, first used in Africa, laterspread throughout America and Indonesia in the seventeenth century as a result ofEuropean colonialism [1]. The first technologies for oil recovery were mortar and stonemills used for olive fruits. In these old machines, the oil flowed through small holeslocated at the bottom of the grinding tanks where it was collected for use [2]. In smallquantities, olive oil was obtained with the addition of water, from which, after millingand through a flotation process, the“virgin oil”was recovered. The latter was consid-ered high quality and commonly called“maiden oil,”and was used for food and rit-uals [3]. Rendering was used extensively for animal fats and oleaginous fruit recovery.In hot climates, the fruits were piled up in the sun and, as a consequence of the pres-sure and the effect of solar heating, exudates of vegetable oil were obtained, a processthat is still currently used in some regions, with some slight improvements. To obtainpalm oil, the fruits are heated with water to produce the exudate [4].The pressing of pulps or seeds is known from preindustrial records of archaeolog-ical, historical, and artistic sources of ancestral agriculture offered by Cato the Elderin hisAgriculture, and from Pliny the Elder in hisNatural History. Frankel [5] made anextensive review of the bibliography on the production of wine and olive oil, wherehe reports identical operating schemes for grinding, pressing, and separation.