Media & Eductional |

Media and Eductional

The fact that the macadamia nut had its origins in Australia is not widely known. Our "Australian Bush Nut" was first discovered by Allan Cunningham in 1828 but it wasn't until the late 1880s that serious cultivation of these evergreen trees began. The early 1900s marked the beginning of an exciting new industry, when a group of American horticulturists transported some macadamia seeds to Hawaii and began growing and grafting selections of these nuts to develop today's agricultural success story.

It wasn't until the 1960s that Australians realized the potential of this indigenous tree nut and began local cultivation. Trees, grafted from successful Hawaiian varieties, were brought to the rolling hills of north eastern New South Wales and south eastern Queensland where over 40% of the world's production is now grown. Australian macadamias have developed a world-wide reputation for the finest quality, flavour and texture.

Macadamia nut trees grow best in sub-tropical climates where rainfall is gentle and plentiful during the spring flowering season and early autumn just prior to harvest. Cold climates are not suitable for macadamias as frost can severely damage the root system which is fairly close to the ground surface. Most varieties of macadamia trees take approximately 10 years to reach maturity and maximum yields of nut-in-shell. Root stock is cultivated from nursery seedlings during the first two years then grafted to create specific tree varieties prior to transplanting to the farm in years 3 and 4. Careful attention to good farm management during these formative years is critical if the long wait is to produce good commercial results. Approximately 250 - 300 trees are planted per hectare, depending on desired spacing, to create the neat and tidy plantations that are the hallmark of the Australian industry. Mature macadamia trees grow to heights of 12-15 metres; they have dark, shiny leaves and bear sprays of long, delicate, sweet smelling white blossoms, called racemes.

The annual growing cycle takes some 9 months. The first flowering occurs in early spring with nut formation in clusters during early summer. Each spray of 40-50 flowers produces from 4 - 15 "nutlets" which eventually ripen into nuts. By early autumn large clusters of plump green nuts are very visible and harvesting commences in late autumn and through the winter months.

Macadamia nuts are allowed to fall to the ground naturally as shaking the trees can damage the delicate root system and negatively affect future production. Modern machinery is now used to gather the nuts and the soft outer husk is then removed on the farm before the nuts are placed in storage silos awaiting delivery to the processing plant. The hard, round, nut-in-shell is transported by truck to the factory where they are weighed and samples from each farm are analysed by the laboratory for quality and moisture content. At a suitable time nuts are moved from storage silos to drying silos where heat is applied to dry them down from 10-15% moisture to 3% moisture in preparation for cracking.

After drying, a specially designed cracker breaks the rock hard shell with minimal damage to the delicate kernel. Both shell fragments and kernel travel along conveyors past an air separation system and through modern, hi-tech, electronic colour sorters which separate the shell fragment from the kernel. These sorters differentiate between the dark brown colour of shell and the creamy colour of kernel and remove the shell fragments with a burst of compressed air. A final hand sorting inspection is carried out, to remove poor quality kernel, just prior to grading the kernel for packing.

Macadamia kernel is graded into "Styles" numbered from 0 to 8 which represent the sizes of the kernel pieces. Style 0 is large whole kernel, style 2 is a mixture of wholes and halves, style 4 is primarily half kernels and higher numbers, 5-8 relate to various sizes of chips and small pieces. Once sorted into styles the kernel is vacuum packed into poly lined, foil bags then into sturdy shipper cartons ready for sale to manufacturers of various value added products such as chocolates, biscuits, snack packs and ice cream.