Macadamia nuts
Macadamia nuts are one of the most delicious nuts in the World. They are crispy with buttery flavour and can be used for preparation of a number of enjoyable foods, like cakes and cookies. Raw, roasted, fried, salted, caramelised or chocolate covered, they are popular in the market all around the world. In addition, they have a high content of monounsaturated fatty acids which significantly reduce cholesterol.
Nutrition and bioactive compounds
Macadamia nuts are high energy food. Highest quality kernels contain 72-78% of oil, most of which are unsaturated fatty acids (more than 80%). Macadamia is rich in amino acids, containing most of the essential ones, and minerals (magnesium, calcium, zinc, potassium and sodium). The content depends on the Macadamia nut's variety, cultivation, method of extraction and geographical region.
Macadamia nuts are one of the rare food sources that contain palmitoleic acid, beneficiary fatty acid with anti-inflammatory and lipid lowering activity, leading to prevention of the metabolic syndrome, including cardiovascular disease and insulin resistance associated with diabetes and obesity. Macadamia nuts also poses anti-oxidative capacity, which was mostly contributed to the polyphenols and squalene.
Cultivation
The macadamia nut tree originates from Australia and was introduced to mostly tropical climates all around the world, where it's now cultivated. Most delicious nuts presumably come from Hawaii, where the tree was introduced already in 1880.
The macadamia tree begins to produce commercial quantities of seeds only when it’s 7–10 years old but may continue for over 100 years. Trees prefer fertile, well-drained soils, a rainfall of 1,000–2,000 mm, and temperature above 10°C (50°F), with an optimum temperature of 25°C (80°F). They are usually propagated by grafting.
Uses
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Kernels: food, macadamia butter for cooking, oil for cooking and cosmetics (creams and other skin products, sunscreens, shampoos and hair products, soaps etc.).
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Nut shells: mulch, fertiliser (after composting), fuel for processing the macadamia nuts and planting medium.
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The remaining press cake from oil production has a great potential to be included in the animal feed.
Market and production
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Worldwide estimated crop in 2020: more than 62,800 metric tonnes (INC). Largest producers include Australia, Hawaii, Brazil, Indonesia, Peru, Fiji, Kenya, Israel, Colombia, Venezuela, New Zealand, Eastern and Southern Africa.
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Largest consumers of South African macadamia were the United States (38%), followed by Vietnam (20%) and China (17%). The market is predicted to grow due to the demand of food and food supplements with the health benefits.