Other Names : Sclerocarya birrea, See also : Marula
Health benefits and Uses of Marula Oil
Marula kernels and oil make an important contribution to the diet of many rural African people in Mozambique, Namibia, South Africa, and Zimbabwe.It also plays an important role in the diet of the San (the indigenous people of the Kalahari desert in Botswana and northern South Africa). The kernels have also been reported to provide sustenance on long journeys. Men walking from Tzaneen in Limpopo Province to the diamond mines at Kimberley in Northern Cape Province take marula kernels mixed with millet meal in a large horn, slung over their shoulder, as the only sustenance for the long journey. The oily kernels are eaten as nuts, fresh or roasted, or stamped to form a cake which can be eaten on its own. The cake is occasionally used to feed animals.The kernels are also pounded or ground into powder that is added to sauces, soups, and other foods, such as biscuits and porridge. The kernels have a delicious flavor and are regarded by many indigenous people as the “Food of Kings” because of the hard work required to obtain even a small quantity from the hard seeds.Due to their high fat, protein, and mineral content, the seeds provide a valuable emergency food during seasons of food shortage. Krige reported that marula seeds were once an important staple food in drier regions of the Limpopo Province of South Africa and that in Mpumalanga Province of South Africa, the Phalaborwa ethnic group (which is locally regarded as a “Marula culture”) subsisted largely on the stored nuts during the winter dry season.1 Similarly, Cunningham showed that on the Maputaland coastal plain in KwaZulu-Natal Province, the nuts are still stored and provide a major source of protein during drought periods. Marula kernels have also been used as a famine food in Zambia and Tanzania. Marula oil is considered a luxury food and is added to a wide variety of traditional and modern recipes. It is a key ingredient in a number of indigenous dishes to add a nutritious, rich nutty flavor and a smooth, buttery texture to foods. It is also used as cooking oil for garnish and salad dressing.
The oil has also been reported to have food-preservative properties, and it has been used by Venda and Shangaan people in the northern part of South Africa to drip onto meat before it is air-dried for storage as biltong (South African dried meat) or jerky.6 The meat is steamed over boiling water, moistened gradually with marula oil, and stored in a cool place. Meat preserved in this way is stored up to a year. The Pedi ethnic group who inhabit the Limpopo Province of South Africa use the seeds in porridge and also as a condiment. For years, Tonga women in Zambia and Zimbabwe have used the roasted nuts as food and used marula oil as a skin softener and meat preservative.
There are 2 basic types of marula oil: heated and raw. Raw marula oil is less commonly used as local people say it only stays fresh for a short while before becoming rancid. Raw oil is preferred when used as a topical application and to prevent minor ailments; therefore, it is produced in small quantities. Heat-treated oil, usually with salt added, is the most commonly used marula oil and is preferred because of the improved taste and its ability to be stored for use throughout the year without becoming rancid.
Marula oil is also reputed to have medicinal properties. It is used as a balm to treat ear, eye, and nose problems, especially in children. It can also be used to treat coughs, diarrhea, and wounds when applied topically. Burning the seeds and inhaling the smoke is a traditional cure for treating headaches. The oil is believed to prevent colds and flu and to soothe colic in babies. A few drops of pure marula oil should be administered before the infant has eaten anything else. Shangaan traditional healers from southern Mozambique regard the seeds as a symbol of medicine in the set of divining “bones” used during divination ceremonies.
Marula oil has great cultural significance in traditional rituals and is given as a gift as a token of respect. Marula oil is also given as a gift to mothers who have just given birth so that it can be used topically and orally by both the mother and her newborn. Among the Zulu people, the marula tree symbolizes women’s fertility, softness, and tenderness, and newborn girls are welcomed into the world with traditional marula ceremonies.
The soothing oil from the marula tree is used by rural people all over southern Africa as an emollient when massaged onto the face, feet, and hands. It is used across the region to treat cracked, dry, or damaged skin (F. Taylor, e-mail, July 14, 2007). Zulu women used marula oil as a beauty treatment for cracked skin on the hands, feet, and lips.It is still widely used by the Tsonga people of South Africa and Mozambique as a baby oil and moisturizer for women’s skin.Anecdotal evidence suggests that rural pregnant women apply it to prevent stretch marks. In north central Namibia, Owambo women use it as a moisturizing lotion, which is applied to the whole body, especially for the bride during wedding ceremonies. It is also mixed with millet grains for use as a traditional body scrub and skin exfoliator. Marula oil has been mixed with red ochre and smeared on women’s hair and bodies for ornamentation. It’s also used to repel insects and moisturize the skin during the dry season.
Marula oil has a clear, pale, yellowish-pink color and a pleasant nutty aroma. The oil is prized for its nutritional, antioxidant, free radical scavenging and moisturizing properties. Marula oil contains a large proportion of mono-unsaturated fatty acids and natural antioxidants. It can be classified as a high-oleic acid (7080%) with relatively low tocopherol content. The stability of the oil is therefore attributed to its particular fatty acid composition. Recent studies have suggested that some of the minor components in the oil, such as sterols, may contribute to this important anti-oxidant property. Marula oil contains a similar fatty acid composition to olive oil and may be as stable to oxidation. The oxidative stability exhibited by this oil could explain its use as a traditional food preservative, and its equally exceptional resistance to oxidative rancidity. Flavonoids may also contribute to the antioxidant activity. However, like all fixed oils, it is also subject to hydrolytic rancidity, whereby triglycerides are attacked by moisture and enzymes to create free fatty acids and glycerol. Owing to its high oxidative stability, marula oil is highly suitable for use as a frying oil or as a coating on dried fruit. It may also be useful for replacing the high-oleic safflower oil used in baby food formulas.
Depending on the extraction process used, marula oil has been shown to have good free radical scavenging properties attributed to a non triglyceride fraction (which varies from 3,800 to 4,300 mg/ kg). Research into the identification of this fraction is ongoing.
Containing high proportions of oleic acid as well as 4% to 7% linoleic fatty acid, marula oil is easily absorbed, making the oil potentially useful for topical application. Marula oil has also been shown to improve skin hydration and smoothness, and it also reduces redness.
Preliminary tests to investigate the commercial potential of marula oil as an ingredient in cosmetic formulations have been successfully carried out . In vitro tests included skin hydration, transepidermal water loss, and “increase in skin smoothness with marula oil performing significantly well