Latin Name - Macadamia ternifolia, M. integrifolia
Ternifolia referes to the fact that the leaves are grouped in three, whereas integrifolia means with entire uncut leaves. Known as the Australian bush nut, the Queensland nut, the bauple nut and the popplenut. To the aboriginal people it is the Kindal- Kindal.
The Plant and its Environment
The macadamia tree is a native to Australia, and grows naturally in the sub-tropical forests of northeast New South Wales and souteast Queensland. The original trees were discovered by the settlers of the mid 19th century, and today the nuts (and hence the oil) are derived from hybrid plants developed from the original trees. The tree averages 11 metres (36 feet) but sometimes achieves 20 metres (65 feet) in height. It bears creamy white or pale pink blossom and is self pollinating, yielding 25-45 kg (55-100lb) of nuts per season. The kernel is housed in a very hard brown shell which is within a green outer husk.
The oil is mostly made up of triacylglycerols that contain monounsaturated fatty acid unit (80%), Macadamia oil is particularly unusual in having a high proportion of palmitoleic acid units (these units are also found in whales, dolphins etc at about 12-15%).
Method of Extraction
The oil is cold pressed (at the low temperature of 30-35C and is available either refined or unrefined. In both cases solvents are not used and the oil retains its natural properties.
|Type||Based On||Content - %|
|Saturated fatty units|
|Typical saturated fatty acid unit content|
|C20:0||eicosenoic acid||<2.5 max|
|Typical monounsaturated fatty acid unit and content||83|
|Polyunsaturated fatty acid units|
|Typical polyunsaturated fatty acid unit content||2|
Odour Faint, slightly nutty aroma
Acid Value 0.2
Specific gravity 0.910-0.929
Therapeutic Properties - internal use
Macadamia oil has a mild laxative action. Monounsaturated oils, duch as macadamia, are effective in reducing the level of low density lipoprotein cholesterol (LDL) without lowering the high density lipoprotein cholesterol (HDI.) and decrease the suspectibility of LDL to oxidation (Reaven el al 1991).
Therapeutic Properties - External Use
This oil makes a pleasant massage oil with good keeping properties as it has a good resistance to rancidity. It is a skin lubricant, and is easily absorbed by the skin; it has been described as a 'vanishing ' oil. The high levels of palmitoleic acid units present in macadamia oil are not found in any other known plant oil: they are found in human sebum, especially in the young. As ageing takes place the concentration falls, so it may be that macadamia oil could be beneficial for the skin of older people (Anon 1991)
Macadamia oil is used in products that afford protection from the ageing effects of the sun; it may replace shark liver and mineral oil in skincare products. In hair care, it is utilized in brilliantines and hot oil conditioning treatments.
Skin tests carried out over 4 years on a range of subjects (different skin types and ages) have failed to reveal any toxic effects, irritation or allergic reactions (Minroba undated).
Reference: Carrier Oils for Aromatherapy & Massage-Len Price with Ian Smith & Shirley Price