Merlo Coffee’s brand new roasted coffee colour sorter

Anna Kerwick @ 2023-02-22 12:02:19 +1000

It was an ordinary Spring day in late 2016 when the large, non-descript wooden crate was delivered into the roasting area at Merlo head office in Bowen Hills.

We all wondered what was in store for us as we took this next exciting step in Merlo’s quality evolution.

The crate sat in the corner, like an unopened gift under the Christmas tree, until the start of the new year when we finally got to crack it open and play with our new toy…

The precious cargo inside was an ASM colour sorting machine. Sounds very exciting, but what exactly does it do?



In a nutshell, our new machine will do precisely what the name suggests – it will sort roasted coffee beans by colour. Simple, but really not.

After carefully roasting to a lovely medium to dark roast, our coffee will pass through the colour sorter over an infra-red laser reader, then pass through twice more for good measure. In both passes, any beans that are lighter or darker than our specified parameters will be separated from the batch.

There are many reasons why a colour variance can occur in roasted coffee, from imperfect raw input, under or over-ripe coffee, bean density variance, poor sorting or inconsistent grading. It could also be due to over or under roasting, as well as damaged, broken or chipped beans.

Before any of us would get to see this machine in action, we had to first build new infrastructure to support the full colour sorting unit and integrate it with our existing roaster set-up.

Everything from platforms to pipe-work, vacuum pumps to dust extraction and even its own compressor needed to be assembled and wired up before we would get to see just what this fancy new machine could do.



A small army of Italian engineers, local sparkies, builders and a team of Merlo staff all worked hard, sweating (and laughing) together through one of Brisbane’s hotter summers to bring our vision for quality improvement to life.

One fateful day in February, after all the drilling and banging had stopped, the ASM colour sorter sprang to life. All that remains to be seen now is the results.

I will personally be surprised if we see a large amount of beans rejected, given the already high quality raw beans we import and the precise roasting profiles we use.

That said, I believe this is a big step in Merlo’s overall approach to providing the highest quality product and is reflective of our vision for best practice and commitment to ongoing quality improvement.

I will keep you posted on how the ASM colour sorter performs, and hope you will also notice the improvement in your cup of coffee!

Of course, the ultimate goal of everything we do here at Merlo is to bring you a premium coffee experience.