Extraction of the argan oilTraditional methodThe production of argan oil, which is still mostly done by traditional methods, is a lengthy process done by women. The most labour intensive part of oil-extraction is removal of the soft pulp (afiash in Berber) and dry them in the sun, and then the cracking by hand, between two stones, of the very hard nut. The seeds are then removed and gently roasted. This roasting accounts for part of the oil's distinctive, nutty flavour. The traditional technique for oil extraction is to grind the roasted seeds to dough, with a little water, in a stone rotary quern. The paste is then squeezed between hands to extract the oil. The extracted paste, amlou, is still oil-rich. Oil produced by this method will keep 3-6 months, and will be produced as needed in a family, from a store of the kernels, which will keep for 20 years unopened. Press-extractionNow increasingly important for oil produced for sale, as the oil will keep 12-18 months and extraction is much faster. Using mechanical presses, mixing of the dough and water is unnecessary and the dough can be directly pressed. All other steps remaining unchanged, the oil is obtained in about 43% yield (calculated from the kernels) and only two hours are needed to get one litre of oil that preserves correctly. Solvent-extractionFor industrial or laboratory purposes, argan oil can be extracted from ground kernels using any volatile lipophilic solvent. After evaporation of this latter, and one or two cycles of extraction, the oil is obtained in 50 to 55% yield. This type of extraction furnishes an oil with unsatisfactory organoleptic properties compared to the traditional or press extraction, which is exclusively reserved to prepare argan oil for cosmetic purposes. Properties and Use of the argan oil
Argan oil is exceptionally rich in natural tocopherols (vitamin E), rich in phenols and phenolic acid, rich in carotenes, rich in squalene, rich in essential fatty acids, 80% unsaturated fatty acids[3] and depending on extraction method more resistant to oxidation than olive oil. Argan oil is used for dipping bread, on couscous, salads and similar uses. The residue from traditional oil extraction is a thick chocolate-coloured paste called "amlou" which is sweetened and served as a dip for bread at breakfast time. It flavour is similar to that of peanut butter. The unroasted oil is traditionally used as a treatment for skin diseases, and has found favour with cosmetics industrie. Medicinal usesThere has been research into argan oil's viability in the treatment of psoriasis with promising results. [4] Argan oil is sold in Morocco, sometimes to tourists as a £10 per 250 ml luxury item (although difficult to find outside the region of production), sometimes in ordinary shops and supermarkets for £10 per litre, and is of increasing interest to cosmetics companies. It was very difficult to buy the oil outside Morocco, but in 2001-2002 argan oil suddenly became a fashionable food in Europe and North America. It is now widely available in specialist shops and, sometimes, in supermarkets. Its price ($20-30 for 250 ml) reflects its status as a fashionable superfood. Goats like the pulp of argan fruits and often try to climb the trees to get at them. They will digest the pulp, but shed the undigested seeds in their feces.[2] As these have shells that are somewhat softened and easier to crack, they are occasionally used to produce oil for non-culinary purposes. An urban legend has it that all argan oil is produced this way. This myth seems to be based on the fact that occasionally, shrewd traders would have sold (and may still try to sell) such "non-food grade" argan oil to ignorant travellers or tourists. The fact that the nuts acquire a foul aroma in passing through the animal's digestive tract makes it easy to tell this oil apart from food-grade produce with its rich, walnut oil-like flavor (Nouaim 2005). ImagesReferencesGeneral references
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