Posted on

Macadamia Processing

 

MacNut Farms is not just New Zealand’s largest macadamia orchard but also the largest macadamia processing facility. We process all our own orchard’s nuts as well as macadamias from many other orchards in the North Island. MacNut aims to be the processor of choice to NZ growers by offering an efficient and competitive service.The processing operation is broken into the stages detailed below:
Dehusking
Once the nuts are picked they are loaded into the hopper which feeds the dehusker (right). The dehusker has two rotating rollers which rip the tough outer husk from the nut. The brown nut that emerges has a moisture content of around 25% and weighs only about 46 % of the total. The huskings are composted and mixed with chicken litter to be used as fertiliser the following year. The hopper & dehusker
Drying
Macadamias hung out to dry To allow the nut to be cracked and the crunchy taste to develop they must be dried from 25% moisture after dehusking to 3% before cracking occurs. At MacNut this is a two stage process. First the nuts are stored in a green house, which allows moisture content to be reduced to less than 10%, then they are moved to a heated container with temperature between 40 – 50 deg C for a week to reduce the moisture to 3%. As you can see (above) we store our nuts in onion bags to allow airflow and easy handling. Each bag contains about 15 kg of nuts
Cracking

The nuts leave the dryer and are put in the cracker hopper. The cracker consists of rotating knives that crack the nuts in a wedge shape.

The loose kernel and the nutshells then enter the trommel (shown below). The trommel is a rotating sieve with holes that get larger along its length. Small pieces fall out at the start and larger pieces further on, with any uncracked nuts rolling out the end to be re-cracked with the next batch

Once the pieces have fallen through the holes in the trommel the shell is separated from the kernel using air blowers. As the nut and shell fall down air passes upwards. The lighter shell pieces are blown upwards into collection bins while the denser kernel falls onto the conveyor belt for hand sorting.The trommel in action

The waste shell makes a beautiful and unique driveway surface at the orchard – always a source of interest with visitors. The local birds have developed a taste for macadamia scraps left in the shells on the driveway. We sell shell in bags or in bulk by special request.

On average we recover about 30 % of the nut weight as kernel the remaining 70 % is shell and waste.

The cracker and sorting operation is run on average 6 hrs a day, 5 days a week and can process around 500 kg of kernel each day. At the end of each day the equipment is cleaned and disinfected. Over a whole year MacNut Farms processes around 100 tonnes of nut in shell.

Sorting, Cooking and Packaging

The hard work starts once the kernel arrives on the conveyor belt. Here our staff separate the kernel into different types (chips, halves, wholes) and sizes. They also discard any bad or immature kernel and shell pieces.

The kernel is sold as raw, roasted and salted, chocolate coated, manuka honey coated, or our special Kiwimac. (half macadamia and half kiwifruit in chocolate). The chocolate coating is done under contract for us and returned packaged.

Hand sorting macadamiasTake a tip from us and taste our special large wholes in chocolate.  Most manufacturers who buy from us ask for small whole kernel so they can give you minimum kernel and maximum chocolate (which is cheaper) –  we give real value with maximum nut and enough chocolate … taste the difference!!

Another favourite variety is the roasted and salted nut, which is cooked on site. The bulk raw nut is lightly cooked in coconut oil in 2kg batches for 3 minutes, sprinkled with salt and excess salt and oil rubbed off to give a crisp and full flavoured product.

Each type is packed in bulk bins or boxes for shipment to our wholesale clients.

For our retail foil packs we carefully weigh and nitrogen purge to give you a long shelf life whether it be raw, salted or chocolate coated.

Share This
Facebooktwittergoogle_pluspinterest