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Catch up

October 11, 2015

I have been pretty busy, in the most positive of ways. There is so much potential for collaboration, exploration and rewarding experiences in coffee.

It’s been a while since I wrote here, so I thought I would do a little summary of the projects I am involved in, a bit about each and the hope of expanding on each in the near future. I have always loved the medium of a blog to get ideas and thoughts down on paper.


Water for Coffee

Several weeks ago, myself and Christopher H Hendon released our self-published book on the topic of water for coffee brewing. This was the culmination of research over the past couple of years. The book has sold really well and the coffee community definitely appear to be enthralled and interested in this amazing topic.

One of the most positive aspects of being able to create a book like this and get it out around the world, is how the dialogue and discussion suddenly widens. There will always be more we can learn with a topic like this, as it is with much in coffee.

An immediate and fundamental point to consider, which has been gained from the input of readers is that of standard water measurement. We are interested in the individual aspects of the water’s mineral composition and how the role they play in the extraction and flavour organising process. However, it has become abundantly clear that the standard unit with which to communicate hardness in water is Calcium Carbonate (CaC03). This basically means that if a specification is written with CaC03 as its reference you then have to figure out a conversion to get your actual amount of calcium for instance.

We have explored this concept in a written corrigendum (an error to be corrected, esp. an error in print). This is available here and is supposed to accompany the original volume. Research into this topic continues, by ourselves and by others. This is an evolving project and we intend to release a volume two next year with additional content.

The particular point to take from this is that it is very important to know that these two ways of expressing mineral content exist. This is specifically important when interpreting a specification and when understanding the result from a measurement device that may measure in either expression.

For example take two interpretations of the SCAA water metric.  The larger box interprets the numbers presented by the SCAA as straight ion whereas the other box denotes the same numbers when considered as CaC03, therefore resulting in a lower actual ion reading.

scaa water

More research

Coffee is full of hidden details that can be better understood and explored though scientific practice. A personal fascination of mine is coffee grinding. I have written about this at length before, here and here.

There is doubtless much research to be done with grinding, as it seems that when one question develops an answer, then several more questions arise, with the potential of several more tests to be done. Like the Water book, research here has greatly benefited from collaboration.

I feel there are several aspects to grinding coffee. There is the distribution of particle size, from the very small to the not so small and what this means for extraction. It’s very hard to test a single variable however, as by grinding coffee differently (by changing the grind) we may be effecting heat transfer during extraction or flow rate during espresso brewing. There is then the issue of dosing and distribution.

One of the topics that was explored in a previous blog here and has been expanded on by others is the impact that the temperature of the bean has on the particle distribution of the ground coffee when the burr setting remains constant. This presents a good test as the variables are controllable and the answer we are looking for can be relatively easily measured. Well, you need a laser particle analyser, which Chris managed to wrangle for a day’s use in our shop.

Myself, Chris, Matt Perger, Cristian Klatt from Mahlkonig and others, are currently finalising a paper to be submitted for review and hopeful publication on the effects of heating on particle distribution. The paper will include some other interesting and surprising findings.

One of the revelatory perspectives I have found and like to present, is the 3 various ways that a particle analyser can display the same information. Below is an image of one set of data interpreted to represent volume percentage, surface area contribution and number count.

partivle dist

I find this a tremendous display of how the question asked can completely change the answer based on the same topic, in this case data on ground coffee. Volume % denotes how much of the overall volume of the ground coffee is taken up by that particular size of ground. A boulder or larger particle will take up a lot of volume and present itself as prominent on a graph that interprets only volume. Smaller particles will take up a fraction of the space and will appear less important in this interpretation. When the data is adjusted for contribution to surface area, everything changes and the smaller pieces become far more influential and start to dominate the interpretation. They may take up less space but they contribute a lot to surface area. Lastly we have number count. This changes everything again. In this espresso grind the particles under 100 microns contribute to roughly 20% (this number is derived only from this data and one grinder model) of the volume but this twenty percent is made up of a hell of a lot of those small pieces. When we change the data interpretation for number count the data suggests there are almost no pieces over hundred microns. Fascinating stuff!


Colonna – Sourcing and roasting

We have started a roastery, well just about. We have a premises, some rather special green coffee and various equipment making its way through customs. We are tremendously excited by this project. I could explain the concepts behind the project here, but an interview by Sam Maccuaig for Sprudge does a great job. You can find it here.

A lot more on this venture coming soon.



Sanremo are an interesting company, one undergoing a massive change of direction. This started with a collaboration with John Gordon a few years back and resulted in the Opera espresso Machine. This machine will be presented in its final updated V2 form at Host in Milan in a few weeks. It will be accompanied by other new projects that Sanremo have been exploring. This year I was asked to become part of an international development team. Together we are working on new equipment aimed at the cutting edge of what’s possible.

I joined this project not only because it provides an opportunity to get behind the scenes, to learn more about, and be involved in the technology that we utilise to make delicious coffee, but also because the company proved to me to have a flexibility to become inspired by a concept or a goal and to approach it creatively and to make it happen. The international group I’m working with is of an amazing quality and it’s very exciting to see where we can go together.

If you are at Host I hope to see you there and to serve you some Colonna coffee; that is if a certain roaster makes it through customs in time.


WBC development board

I guess you could say I am currently retired from competition. Never say never, but I won’t be competing for at least 3 years. I took the opportunity to become involved in the WBC development committee which is currently exploring how we can evolve and develop the World Barista Championship. Being so heavily invested and involved as a competitor, it is fascinating and rewarding for me to get behind the scenes. The coffee competitions have played a huge role in the speciality coffee community and I am sure they will continue to do so.

It’s intriguing to assess something that is already very successful and to look at where it can go. It is easy to criticise something like the WBC, I myself have been a critic of certain aspects during my competitive career. I do think the competition can improve, but it’s also important to be aware of what works, of what makes it special and to maintain that whilst addressing the elements that can improve.

Unfortunately (but also naturally and sensibly) I can’t divulge the details of this process. You’ll just have to wait and see what changes in the coming years.


National Coordinator SCAEUK

Speaking of competitions, I have taken on the role of National Coordinator of the UK chapter of the SCAE.

Much like the WBC board, getting involved in the running of the UK chapter really appealed to me. I am working with a great board over the next couple of years. Our goal is simple really. To take the potential and support for these competitions and to maximise and explore it, creating as much value as possible for all of those involved.

There is a lot of support for the chapter and that has a huge impact on what we are able to do. In summary we are looking to expand the nature of each event, hosting the competitions and the heats at venues that reflect the speciality coffee community. We are looking to further the success of the UK Barista championships but to also make the most of the increasing popularity and potential of the other competitions.

For updates and info keep an eye on the chapter’s website here.

That’s all for now.


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