The Macadamia Story
As Queen of the tree nuts, macadamias are delicious and nutritious with an interesting history.
Macadamia Fast Facts
Indigenous names for the macadamia include ‘Kindal Kindal’, ‘Baupal’ or ‘Boombera’
In the 1900s, a group of American horticulturists transported macadamia seeds and successfully grew them in Hawaii
In the 1960s, Australians realised the potential of macadamias and began local cultivation
Macadamia trees can continue to yield well for up to 60 years with careful management
Macadamia trees grow best in sub-tropical climates and rich well-drained soils.
In Australia, orchard plantings range in location from mid-New South Wales to south eastern Queensland, up to the northern regions of Queensland.
Globally, macadamias are successfully grown throughout South Africa and across Mozambique, Zimbabwe, Malawi, Zambia and Rwanda. More recently they have been successfully grown in Southern China through the Yunnan and Guangxi provinces and south in Vietnam. There is also some cultivation in Central America and northern South America; with Guatemala and Brazil the largest producers in this region.
Macadamia trees are produced by grafting a selected variety onto a root stock seedling, a process that is carried out in specialist nurseries. It takes approximately two years to produce a fully grafted macadamia tree that is ready for planting into an orchard. It then takes a further five to seven years from planting an orchard to harvesting the first commercially viable crop. During this time, and to ensure future profitability, the young trees need regular care with ample water, fertiliser and pruning.
In Australia and South Africa, approximately 250 to 300 trees are planted per hectare to create the neat and tidy plantations that are the hallmark of the industry. Mature macadamia trees can grow to heights of 12 to 15 metres; they have dark, shiny leaves and bear sprays of long, delicate, sweet smelling white blossoms, called racemes.
The first flowering occurs in early spring with small ‘nutlets’ developing shortly after. These nutlets grow and develop through spring and summer – ripening in early autumn. Each spray of 40 to 50 flowers produces from 2 to 15 ‘nutlets’ and by early autumn large clusters of plump green nuts are very visible.
Once nuts have reached full size, the shell begins to harden during December and early January. After the shell has hardened off, the oil accumulation phase begins. This phase lasts for about two months. Mature nuts begin to fall in late autumn and continue to come down over the next six months.
Macadamia farmers harvest the nuts after they have fallen to the ground, completing a harvest round every two to four weeks. Harvested nuts have a fibrous outer layer called a husk which must be removed before the nut is sent to the processor. Farmers do this by using a machine called a dehusker. Once the nuts are dehusked, the farmer inspects them and removes any defective nuts from the batch.
The sorted nuts are then stored on-farm in drying bins or silos until enough quantity is accumulated to make a load. The nut is then transported to a processing factory, where it is weighed, sampled and tested for its quality. Growers are paid for the crop based on both weight and quality of the kernel. During the off-season, farmers will spread organic, rich material under their trees to act as a mulch and natural fertiliser. This mulch is used to maintain a healthy soil environment and promote tree root growth to assist in sustainable production.
Harvesting and Processing
Nut-in-shell delivered to the processor is dried as quickly but as gently as possible to stabilise the kernel. After drying, a specially designed cracker breaks the rock-hard shell. Both shell fragments and kernel travel through an air separation system and through modern, hi-tech, electronic colour sorters which separate the shell fragments from the kernel. These sorters differentiate between the dark brown colour of shell and the creamy colour of the kernel and remove the shell fragments with a burst of compressed air.
A second colour sort and a final hand sorting inspection are carried out to remove reject kernel and grade the remaining kernel both by size and quality. Macadamia kernel is graded into ‘Styles’ numbered from 0 to 7, which represent the sizes and shapes of the kernel pieces. Style 0 is large whole kernel, Style 1 is a smaller whole kernel, Style 4 is a half kernel and Styles 5 through 7 relate to various sizes of chips and small pieces.
Once sorted into styles, the kernel is nitrogen flushed and vacuum packed into foil lined bags and placed inside sturdy cartons, packed ready for sale. These cartons are stored in a climate-controlled warehouse ready for dispatch to food manufacturers and wholesalers or further processed and packaged in retail-ready packs for sale to consumers via the retailers.
Trees nuts are well recognised around the world as one of the most health beneficial food groups and snacks. Macadamias are quickly gaining a reputation for being not only the most delicious and versatile of the tree nuts but also one of the healthiest.
Macadamias are rich in heart-friendly fats, including having the highest percentage of monounsaturated fats out of all the tree nuts, which reduces the risk of heart disease. They are low in saturated fats with zero trans-fats. Health experts around the world agree bad saturated fats in the diet should be replaced with unsaturated fats like those in macadamias.
Boasting some of the highest levels of antioxidants of all tree nuts, macadamias help protect the body against cell damage, disease and cognitive decline. Macadamias are packed with phytochemicals, which have impressive anti-inflammatory effects. Studies show that eating naturally antioxidant-rich macadamia nuts as part of a healthy diet improves oxidative stress.
Nourishing macadamias contain a range of useful nutrients, including manganese that supports collagen production as well as a high amount of palmitoleic acid to boost youthful glow. Macadamias also have calcium, dietary fibre, potassium and protein, which are all vital for good skin. Macadamia oil can also be used in easily-absorbed skin care products to enhance both skin and hair health.
Macadamias contain copper, magnesium and manganese that support healthy neurotransmitters in the brain. They also contain palmitoleic acid, a type of monounsaturated fatty acid important for the myelin sheath, which helps protect nerve cells. Studies show frequent nut consumption may help protect the brain from the effects of ageing and improve memory function.
Low carb and keto friendly
Creamy, buttery macadamias taste delicious, but they can also play an important role in helping maintain a healthy body weight and positively influencing blood glucose levels. Macadamias satisfy hunger and leave the body feeling full longer. They are low in carbs, with only 1.5g net carbs per 28g serving, and high in good fats, making them perfect for a healthy diet, including keto.