The argan or ironwood tree belongs to the Sapotaceae family, sapot plants and is an evergreen plant that is mainly native in southwest Morocco. Other growing areas are Morocco, Algeria, Mauritania and Israel. It grows very slowly, can reach a height of 8 meters and a high age of more than 150 years. Due to its deep roots up to 30 meters, it can also survive long periods of drought.
The gnarled tree does not start to bear fruits until it is about 5 years old. Those are well protected from predators by thorns. The fruits are similar in appearance to an olive and are round to oval with a green, fleshy appearance. If the flesh is removed, a nut appears with 1-4 seeds grown together.
The argan tree is native in southwest Morocco - North Africa - because there are optimal conditions for it to grow. The dry air of the desert and the proximity to the sea give the tree good conditions for its growth. The tree's drought resistance also helps to reduce desert expansion, with sandstorms and sudden rainfall leading to severe soil erosion . Because of its essential importance for the regional ecosystem, a biosphere reserve was initiated in southern Morocco, which promotes sustainable economic activity in harmony with nature.
Flowering can take place all year round - usually the ripe fruit is harvested from June to September. Even if the tree bears fruits after only 5 years, it will only bear enough fruit after 50-60 years to produce enough oil.
Traditionally, harvesting was only done by women: only the dropped fruits were picked up, as thorns disturb and easily breaking branches do not allow shaking. For these reasons, a plantation operation was not possible for a long time. Due to new cultivation and harvesting techniques, a large part of the work is now done mechanically in plantations. An automatic shaker is placed around the trunk and uses vibrations to make the hanging fruit fall. A previously laid out net helps to collect the fruit.
There are three main ways of processing the seeds, all of which provide different oils: traditional or mechanical pressing of the fruit, and solvent extraction. In all three methods, the preparation steps are the same: the fruit is first dried for several days to make it easier to remove the pulp. If the raw nuts are present, they are cracked open to expose the oily seeds. The subsequent use of the oil determines the next step: if the oil is used as cooking oil, the seeds are roasted at an elevated temperature - to deactivate bitter substances. If the oil is used e.g. in the cosmetics industry, roasting is not necessary. Oil from roasted seeds has a hazelnut flavour. In traditional pressing, the seeds are now kneaded by hand with the addition of boiled water until the oil slowly emerges. In this way, about 30% yield of oil can be achieved.
A less labour-intensive process with higher yield can be achieved by mechanical pressing. Here, usually no water is added, whereby the pressing is carried out by cold pressing in oil mills (extrusion). A yield of up to 50% is possible. With this method, an average of approx. 4 litres of argan oil are extracted from 100 kg fruit.
The oils obtained from traditional or mechanical processing are further processed by filtration. The aim is an oil with a homogeneous appearance in colour and haptics.
With the help of organic solvents, vacuum and increased temperatures, the third process, a yield of more than 50% can be achieved from ground seeds. The "Enriched Argan Oil" obtained in this process has a different chemical composition (see below).
Of all three production methods, the remaining press cake can be used as animal feed or fertilizer.
Depending on the production method, the oil obtained has a yellow to orange colour with a pungent, sweetish smell and nut-like taste (enhanced by additional roasting).
More than 94% of the oil consists of triglycerides, of which unsaturated fatty acids such as oleic, linoleic, palmitic and stearic acid make up the major part (>80% of the oil fraction).
Argan oil differs from other oils in the low amounts of myristic, palmitoleic, arachidic and behenic acid. These are only present as trace elements in argan oil. Furthermore, it has a high proportion of biologically active secondary plant substances in relation to other oils: especially to be mentioned the substances tocopherol, sterols and phenols.
The high content of unsaturated fatty acids seems to have a positive effect on plasma LDL cholesterol levels. Nutritionists therefore recommend a ratio of unsaturated to saturated fatty acids of 1.5:1, with argan oil achieving a higher result of 1.8:1. This seems to have positive effects on health: skin aging should be reduced, neurodegenerative processes and cancer development should be prevented.
Tocopherol, also called vitamin E, with its molecular structure can defuse radicals and thus prevent cancer. Sterols and phenols can also reduce the development of tumors.
If the cholesterol level and the formation of radicals are reduced, an antihypertensive effect is often obvious.
Externally, argan oil is used in cosmetics due to its high vitamin E content: The natural water-fat layer of the skin is brought back into balance. Radicals are neutralized, which leads to a stabilization of the connective tissue. This is protected against dehydration and feels firmer, softer and more moisturized. Skin changes such as unphysiological skin aging, youthful acne, skin allergies or stretch marks are positively influenced. It is therefore not surprising that argan oil is used in several cosmetic products: Shampoo, washing lotion, etc.
Argan oil has also found its way into gourmet cuisine for several years and can be used for frying or as a dressing.
The stability of argan oil does not only depend on its storage after the production process, but already starts with the harvest and subsequent preparation of the fruits. The timing of harvesting has an influence on the vitamin E content and is highest in July - especially when the fruits have fallen to the ground without any external influence. After harvesting, the fruits must not be stored/dried for too long to prevent the destruction of important substances. Often the kernels are only harvested in Morocco and pressed overseas. During transport, attention should be paid to ensure correct storage.
Cosmetic argan oil goes bad faster due to the lack of roasting. Argan oil generally has to be protected from light and heat to reduce decay.
Due to its high sales value, argan oil is often blended with low-value oils. To reduce this, the label "Endemic Argan oil of Morocco" was created. A goal is to guarantee the authenticity of the oil from Morocco. If the oil is blended, sunflower or sesame oil is often used. If an analysis is demanded, attention should absolutely be paid to the chemical compound Campesterol. It is sufficiently present in most oils, but in argan oil only in traces (<0.4% total content). Some companies also offer visual or organoleptic test methods, but these do not provide clear data.
The place of cultivation also determines the chemical composition of oils: for example, oil produced in Israel has a different composition than oil produced in Morocco.
If oil is purchased from very small farms in Morocco, testing for bacterial contamination should be done. Traditionally, the seed is collected from feces of sheep and goats. The sheep thus help to remove the pulp in a natural way. However, if these seeds are used for oil production, contamination of the oil is obvious.