Macadamia

Macadamia integrifolia in a plantation

Macadamia is a genus of flowering plants in the family of the silver tree plants ( Proteaceae ). She is primarily known by the fruit that tetraphylla " macadamia nut ", the two species Macadamia integrifolia and Macadamia and their varieties. The only four species occur only in Queensland and New South Wales before in subtropical eastern Australia.

• 2.1 nutrition
• 2.2 toxicity

• 5.1 Notes and references

Description

Appearance and leaves

Macadamia species grow as trees, sometimes with several trunks and reach depending on the type stature heights of 6 to 18 meters. There are more or less strongly buttress roots formed.

In adult specimens the leaves are usually in threes to fifth whorls arranged on the branches. The more or less clear ( 0 to 18 mm long) stalked leaves have a simple leaf blade with depending on the type and age of specimens smooth or stachelspitzigem margin.

Inflorescences and flowers

The lateral or terminal, pseudo- racemose inflorescences are always simple, in contrast to the previously classified here also species of the genus Lasjia with branched inflorescences. Always two stalked flowers are borne on a more or less transitory early bract. The hermaphrodite flowers are radial symmetry ( at Triunia they are easy zygomorphic ) and cruciform. There are only four bracts available and they can be grown freely or with one another. The cream-colored, cream - brown or pink bracts are belt- shaped with enlarged upper end; they curl up in the course of anthesis eventually return. There are only four stamens present. The stamens are fused part of its length with the bloom cladding. The connectives surpass anything the dust bag. The bare nectar glands are fused and form a ring around the ovary around ( at Triunia they are free ). Each flower contains only one sitting, bald until silky haired, Upper constant carpel. The carpel contains only two orthotropic ovules. The stalk round to slightly quadrangular style ends in an oval or club-shaped scar.

Fruit and seeds

The spherical follicles have at the top of a horn. The follicles do not open until late along a more or less distinct longitudinal seam and usually contain only one seed. The wingless, globular to broadly ovate seed has a brown, smooth or wrinkled, hard seed coat ( testa). The embryo has two cream-colored, spherical, sweet, bland or bitter tasting seed leaves ( cotyledons ).

Use

Economically important are only two ways: Macadamia tetraphylla ( their nuts have a rough shell and are not suitable for roasting ) and macadamia ternifolia ( with a smooth but slightly thinner shell ). Only these two species bring forth directly edible nuts; the nuts of the other species are too bitter to be edible, but were historically made available by grinding and prolonged leaching of some Aboriginal peoples.

Even the Aborigines, the indigenous people of Australia, took advantage of the wild nuts as a protein - and fat- rich food source. One of the traditional names of their languages ​​is " Kindal Kindal ".

Macadamia nuts are considered to be very fine and tasty nuts. In addition, they are due to the difficult cultivation, complicated further processing and in particular the increased demand for the most expensive nuts in the world - hence the name "Queen of Nuts ".

The nuts ripen on the trees and are harvested from the ground. Leave to it well ventilated to months store a few weeks in order to reduce their water content from the original 30 percent to about 1.5 to 2 percent. Thus they are easier to crack. The nuts are almost exclusively peeled or processed further into the trade because their shell is very hard and relatively thick. You can be the most conventional Nutcracker non-opening, best suitable special spindle Nutcracker.

In addition to the very high levels of fat (mostly mono- and polyunsaturated fatty acids) they contain, among other things, vitamin B, calcium, iron and phosphorus. The oil also is used in the cosmetics industry, for example, as an exclusive body oil.

Nutritional value

Nutritional value per 100 g (edible, roasted, without salt )

• Calorific value 3005 kJ (718 kcal) Protein 7.79 g
• 72.64 g of fat, of which 16 % saturated fatty acids
• 2 % omega -6 fatty acids
• 1% Omega -3 fatty acids
• 81 % monounsaturated fatty acids

• Potassium 363 mg
• Phosphorus 198 mg
• Magnesium 118 mg
• Calcium 70 mg
• Sodium 4 mg
• Zinc 1.29 mg
• Iron 2.65 mg

• Niacin (B3), 2.27 mg
• α -tocopherol ( E) 0.57 mg
• Pantothenic acid (B5) 0.60 mg
• Thiamine ( B1) 0.71 mg
• Pyridoxine (B6 ) 0.35 mg
• Riboflavin ( B2) 0.08 mg
• Folic acid (B9) 10 ug

Toxicity

Macadamia nuts are toxic to dogs. Constipation, weakness and paralysis of the abdomen are the result of approximately 12 hours after admission. Depending on the amount and size of the dog foods eaten also muscle twitching, joint pain and pain may follow in the abdomen. With a larger amount of foods eaten opiates can mitigate the effects to subside. After 24 to 48 hours is usually effected complete recovery.

Home hazards and regions

All since 2008, only four Macadamia species are originally from Queensland and the adjacent New South Wales in eastern Australia. They occur only in a 500 -km-long strip on the east coast in a subtropical area.

Despite the high demands of the little trees grew joyful today include: Australia, Hawaii ( the largest), New Zealand, South Africa, Malawi, Kenya, Israel, Brazil, California, Guatemala and Paraguay to the growing areas. Macadamia is the only australischstämmige food plant that reaches a significant scale in world trade.

At least the species Macadamia Macadamia integrifolia tetraphylla and are now in New South Wales as endangered.

Systematics and botanical history

Around 1857, the first type was Macadamia ternifolia by botanist Ferdinand von Mueller and Walter Hill, the director of the Botanical Garden of Brisbane, discovered in a forest on the Pine River Moreton Bay. The genus name honors the Macadamia friendly scientist John Macadam ( 1827-1865 ). The genus Macadamia was in 1857 by Ferdinand von Mueller in Account of some new Australian plants in Transactions and Proceedings of the Philosophical Institute of Victoria, 2, pp. 72 with the first description of the type species Macadamia ternifolia F.Muell. positioned.

The genus belongs to the tribe Macadamia Macadamieae in the subfamily within the family Proteaceae Grevilleoideae. Some previously unclassified species in this genus were found in others which are also species-poor genera, for example Lasjia PHWeston & ARMast ( five species), Triunia, Floydia.

It has been around since 2008, only four to ten earlier macadamia ways:

• True macadamia or Queensland nut (Macadamia integrifolia Maiden & Betche )
• Macadamia jansenii C.L.Gross & P.H.Weston
• Trifoliate macadamia nut (Macadamia ternifolia F.Muell. )
• Rauschalige macadamia nut (Macadamia tetraphylla LASJohnson )

Swell

• CL Gross: Flora of Australia Online: Macadamia: Full -text online. (if the direct link just does not work, you can also try the taxon enter into the search field ) (sections reporting and dissemination )
• Austin R. Mast, Crystal L. Willis, Eric H. Jones, Katherine M. Downs & Peter H. Weston: A smaller Macadamia from a more vagile tribe: inference of phylogenetic relationships, divergence times, and diaspore evolution in Macadamia and relatives ( tribe Macadamieae; Proteaceae ), In: American Journal of Botany, Volume 95, Issue 7, 2008, p 865: Full -text online. doi: 10.3732/ajb.0700006 ( section systematics, reporting and dissemination )