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MPC’s new system at Alphadale— a major step forward for growers

With the acceptance of partially dehusked and/or unsorted NIS at MPC’s factory, it is timely to look at how the system works and what growers are are saying.


MPC’s focus on quality is vital for the long-term success of our growers and the industry. It’s all about delivering consumers a nut with a smooth buttery taste and good crunch. If consumers have a good eating experience they will want our product, and if they want it, we are on our way to a bright future.

The key to delivering a good eating experience is to get mature macadamias from the tree as quickly as possible picked, dried and stored in a nitrogen flushed and vacuum packed bag.

Moving macadamias quickly through the supply chain improves quality, and by not having to sort nuts and store for long periods on-farm, there are cost savings for growers.

How does it work?

The new system allows growers to deliver a range of product types:

  • Harvested and on-board dehusked
  • Harvested, on-board dehusked and then rock sorted and dehusked (no sorting)
  • Harvested, dehusked and quickly sorted
  • NIH to the HWNS that is dehusked only, then sorted at MPC (at a cost of $0.06/kg of delivered weight)
  • NIH to the HWNS that is dehusked and sorted if it has high levels of gross rejects (at a cost of $0.16/kg of delivered weight).

All of the above types of products must meet MPC’s delivery specifications to be accepted.

How does MPC treat my product?

When you make a booking at MPC, Ron asks you what type of product you have to deliver (partially dehusked, unsorted etc). This information is used to guide the processes it will need to undergo.

Once received at the factory, an assessment of the product is made and if it looks good then it will be sampled the same way as in past years. The samples will be sent to the NIS laboratory, dried, cracked and the kernel assessed.

If the delivery contains NIH or needs sorting, then the processes required (trash removal, dehusking sorting etc) are undertaken. This is performed on large samples to make the system work efficiently.

MPC has invested in new colour sorting technology (much improved technology) that removes gross defects very efficiently. These machines are new to the macadamia industry and coupled with the improved kernel colour sorters in the factory, the sorting efficiency has been greatly improved.


The graph below shows average total reject levels in consignments for the first three months of the season. You can see the reject levels for 2012 are similar to those of 2009 and considerably lower than 2011.

With most growers now moving to only dehusking and sorting NIS quickly, this is a good result. This graph really highlights why MPC is convinced that our approach is the right way to go.

Total Reject levels for first 3 months of the season 2009-2012


Why does the new system work?

Growers who have recently delivered their NIS to us with little if any sorting have been surprised at how good their results have been. Why?

There are many reasons, but it comes down to a few key things:

  • Growers produce good quality in the paddock and this is being maintained by the speed through the system
  • By removing the need to sort on-farm, the possibility of removing good nuts has been removed.
  • It is hard to sort NIS to make big changes to the overall returns from a consignment. To reduce your reject level by 1%, you need to remove 30kg of reject NIS per tonne. This is a fairly daunting amount and if you have the quality right in the paddock, will you be removing anywhere near this amount?
  • Reduced storage time has reduced the possibility of inducing defects from storage such as discolouration, mould and internal discolouration (Brown centres).

Grower feedback: Kim Wilson – General Manager, Gray Plantations

Gray Plantations owns and manages 25,000 trees in the Lismore area. This season they have chosen to change the way they manage their dehusking and sorting operation as a result of the changes at MPC.

The old way: Previously all nut would be brought in off the harvesters partially dehusked (using on-board dehuskers) and the nuts would be put over a manual rock sorting table (requiring a person to remove rocks and sticks from the nuts), dehusked, hand sorted and then put through a water sorter.

On the first round all nuts would be resorted. For the second harvest round onwards nuts would be tested and only resorted if required.

The new way: In 2012 Kim is now bringing in partially dehusked nuts to his shed, running them across a manual rock sorting table, putting them through a dehusker and into the silo. There is now no manual sorting of the nuts after dehusking and no water sorting.

Kim has decided to still put the nuts through his shed for a few reasons:

  1. He is unable to ensure the harvesters achieve a dehusking rate of 90% or more;
  2. To consolidate nuts for a delivery he needs to put them in a silo and so they need to pass through the shed to do this anyway.

Kim believes the new system is fantastic. “In the past we would have up to three people in the shed working. Now we have one person on the rock table and the nut is going past them much quicker. So that’s a big saving to start with.”

The worker is in the shed making sure all belts, dehuskers etc are running correctly. They are at the rock table, pulling out the biggest rocks and sticks so they don’t go through the dehuskers and cause damage.

Major savings: Kim has found there are significant cost savings. “In the past it would cost us about $0.15/kg to dehusk and sort nuts per kilo at 10% MC. Based on what we have run through this season we are finding it to be around $0.05/kg. On a 300t crop we are looking at saving $30,000. This is a huge saving to us.”

Changing the way things were done was a real leap of faith for Kim. “I walked past the sorting table the other day and saw heaps of nuts going across. I stopped and started to pull rejects out. I had to tell myself I didn’t need to do it anymore and that I should walk away from the shed. Old habits die hard but this a better way of doing things.”

To assess the level of nut in husk remaining after the quick dehusk, Kim found a useful way to work it out. “When we first started I thought, there is a lot of nut in husk, way more than 10%. So I stopped the belt, put a lug bin upside down over some nuts (to get a sample) and then counted the NIH and dehusked nuts. I found that what I thought was lots of NIH was less than 10%. After all these years of training ourselves to see the bad nuts on a table and pull them out, to now letting them go, is hard work.”

And the results? “This season the quality has been really good. Currently we are averaging 2% reject – a good result, considering there is no sorting.”

Kim believes the new system has shown that quality is made in the paddock. “Without sorting, to achieve 2% reject is impressive. It highlights if we focus on producing a good quality product in the paddock then there is little we need to do after that point except for harvest it quickly.”

Grower feedback: John Gough, McLeans Ridges

John Gough owns and manages his own mixed horticultural crop farm at McLeans Ridges. This season he has tried a few different options and has found that the new system introduced by MPC is the way to go.

The old way: In the past John used to use the traditional dehusk, a quick table sort and then water sort prior to loading nuts into a silo. After the nut had dried down he would bring the product back out and do a final hand sort prior to sending the product to the factory.

The new way: Now the system has changed. “I now bring the nuts in, dehusk them, pull out any that weren’t dehusked and any obvious damage on the table. There is no longer a water sorter used and I don’t do a second sort”.

Like many growers, John was unsure if the new system without sorting would work. “Initially I was a bit skeptical so I tried two ways of dealing with the nuts – putting it through the traditional way of sorting it twice and then I did a batch only sorting it once. When I sorted it twice I pulled out about 20kgs. When I got the consignment results back, it showed there wasn’t any real difference in the quality of the nuts either way I put it through my shed.”

John has found by focusing on ensuring nuts are dehusked and obvious rejects are removed he can save large amounts of labour. As he has a mix of crops to deal with on the farm, labour management is a major issue for him.

Major savings: John estimates he will save between 60-75% of his labour hours by only dehusking and quickly sorting nuts compared to the old way.

From his experience with other crops John knows the quicker you harvest and get product to the consumer, or in the case of nuts, dried and into storage, the better the eating quality.

“My priority is now to harvest as quickly as I can. In a wet year when we have small windows of opportunity to get out and harvest, not having to stop to resort nuts is making a huge difference. I’m focusing on harvesting when I can as I know this gives nuts the best shelf-life”.


So far we have only received positive feedback about the new ways you can deliver product to MPC.

Often people ask: “Why has it taken so long?” or “Why did we invest in all the dehusking and sorting equipment on farm if you were going to introduce this system?”

The answer is technology. Ten years ago and even five years ago the technology simply didn’t exist. Now it does so we are introducing it.

The NIS consignment quality results from growers who are now only dehusking, or dehusking and quickly sorting, are good and no different to what we have seen in other seasons.

It must be remembered that good quality comes from “getting it right in the paddock”, and then moving it quickly through the supply chain. As one grower said “You can’t make a silk purse out of a sows ear”. I think it’s very true for macadamias.