Macadamia trees originated on the wet eastern slopes of the Great Dividing Range in Australia. A source of nutriment for thousands of years these nuts have had various names. Jindilli (later corrupted to kindal kindal) by aborigine in the North and boombera further North. Settlers called them bauple or bopple nuts, bush nuts and Queensland nuts amongst other things. Americans call them Hawaiian nuts. Botanists had the last say in 1858 and the name Macadamia was bestowed on the genus in honour of a scientist John Macadam.

Only two of the Macadamia species produce edible nuts. M.integrifolia and M.tetraphylla. Plantations, some of them enormous, have been established in various subtropical parts of the globe, notably Hawaii, South Africa, Kenya, and of course Australia. In 2001 Australia produced 35,000 tonnes of nuts in shell. In New Zealand macadamia trees were mostly confined to home gardens and orchards until the 1980’s when commercial interest quickened. Despite the reputation as an easy-care plant, achieving crops of commercial size and quality has taken considerable research and labour. The industry in New Zealand could be described as fledgling at this time.

The expense of macadamia nuts and the slowness of the industry to develop are attributed to early difficulties with grafting and harvesting, and the extremely hard shell of the nut. Otherwise the plants thrive in New Zealand. Young trees are frost sensitive but once established grow even where there are frosts. The ease with which macadamia nuts germinate and compete with weed species is evident in our garden where we are continually pulling them out from the vegetable and flowerbeds. They are most productive in warmer parts of the country – the North and coastal subtropical niches.

All parts of the nut have a use. The husk makes excellent mulch or compost. The hard shell is a high temperature fuel or can be ground up to use as abrasive powder in industry or cosmetics. Ever compare your facial scrub with sandblasting – maybe not! We find the shells a useful replacement for gravel in our driveway. As a food the macadamia nut has few equals. It is high in energy and contains no cholesterol at all. In addition it contains a high proportion of mono-unsaturated oils considered to actually reduce cholesterol in the bodyand encourage weight loss.
A typical analysis yields the following:

Raw Kernel – per 100g
Energy		3080kj		Potassium	410mg
Protein		9.2g		Phosphorus	241mg
Fats (total)		74.0g		Calcium	64mg
	Mono-unsaturated	60g		Sodium	2mg
	Poly-unsaturated	4.0g		Iron	2mg
	Saturated	10.0g		Niacin	1.6mg
Carbohydrates total		7.9g		Thiamine(B1)	0.22mg
	Sugars	4.6g		Riboflavin(B2)	0.12mg
Dietary Fibre		6.4g

Health Benefits

A hospital study has found a diet enriched with macadamias actually lowers blood cholesterol levels. It is suggested 6-20 macadamias a day will reduce cholesterol by 7% over 4 weeks.

It is also suggested regular consumption of macadamia nuts protects against coronary heart disease. Macadamias are high in selenium of which we are lacking in New Zealand soils. They also contain phyto oestragens and are rich in magnesium.

Macadamia nut oil has the lowest levels of (omega) w-6 fatty acids of all culinary vegetable oils including olive and canola oils.