Coffee Chat with Dan from Machina Coffee

Machina Coffee roasts coffee, sells coffee equipment, and serves coffee from their cafe Brougham Place, Tollcross, Edinburgh. I have been following their business for a while and I had a few questions about how they roast coffee (which is particularly relevant now that they are roasting some special coffee as part of their Filter Map series).

Dan, a roaster at Machina Coffee, spoke with me about how he roasts coffee, how Machina sources coffee, and a bit about how to a career in the speciality coffee industry as a roaster. I hope you enjoy our discussion.

Could you tell me a bit about yourself and what you do at Machina Coffee?

Hey I’m Dan and I'm one of the lead roasters at Machina Coffee. I've been at Machina for coming up to four years now and have been roasting here for two and a half years. It's such an amazing job that allows me to use my love of spreadsheets and hard data, while also requiring a level of creativity and imagination.

How do you prepare the roaster when you first start your day?

Whenever there is a roast day scheduled the roaster* requires a certain warm up period to ensure consistency. However, the absolute first thing you do is a safety check of the roaster to ensure everything is in working order. Check the gas, check the fans, check the chaff collector, along with various other tasks. Honestly, the last thing you want is something not to turn on or break when you are in the middle of a roast day. The Probat Roaster we use is a hefty bit of machinery and it’s something that should be taken seriously, but I'd be lying if I said I didn't still get a little kick out of hitting the big green button to start the drum spinning.

• this is true for both machine and man - staying warm in the warehouse is a constant battle and whether you are fuelled by propane or bean juice a slow and consistent start to the day is key for smooth operation.

How do you source the coffees you roast? How do you decide which coffees meet your needs as a business?

Picking the best beans: our coffee is all sourced in the same way. We receive offer lists from our green suppliers, spend hours picking out the coffees we think sound interesting, order samples, roast according to processing on our IKAWA sample roaster, then cup, and pick the best. Simple and straightforward in theory, however it never seems to be in reality. Coffee is a fickle beast fraught with inconsistencies and a myriad of variables to consider. We've had tables of 20 coffees and picked none and we have had other days when we find three or four surprise bangers.

Sometimes coffees will taste one way pre-shipment and then completely different once it lands. Some age faster than others and some have defects that are undetectable until you roast a larger volume. All coffees come with an SCA Score, but this can also be misleading if you’re not careful and don’t do the necessary due diligence.

What skills do you think are necessary to have to be an effective coffee roaster?

I think it's a combination of being a bit of a perfectionist but also having realistic expectations in terms of what is achievable. With every coffee I've ever roasted I've always set out with the intention of it being perfect, but I've never once achieved that goal (I’m very self-critical!). There is always something to tweak or a slightly better approach that could have been taken with the benefit of hindsight. So, if you are happy to constantly strive for perfection but be willing to learn from failure, then you'll make a great roaster.

Can you walk me through the stages of roasting coffee? How do you know a roast is ready to come out of the roaster?

A lot of roasting is trial and error. The more proficient you are the better your guesses can be but there is no one comprehensive, catch-all solution to roasting great coffee. When we first get a new coffee in, we look at origin, MASL (metres above sea level), varietal, moisture, plus a whole load of other things. Based on this, we seek to make assumptions about how the coffee will behave and then set certain targets to reach during the roast. Ordinarily it usually takes two or three roasts to get a good grasp of the coffee and how it behaves. However, in all honesty it’s virtually impossible to control all the variables but we do our damn best and we feel very lucky to have been blessed with some pretty amazing results.

How do you develop roast profiles for your coffees?

Cup, cup, and cup again. There's no other way of doing it. Roast curves are useful but never tell the whole picture. Once you can start picking out flaws in your coffee on the table you can take that back to the roast curves and try to work out what caused it. Is there a roasty note? Check for flicks towards the end. Is it bready and empty? Check for flattening end temps. Also follow other roasters that are happy to share tips.

Scott Rao's Instagram is a fantastic resource. Scott Rao has been a voice in coffee roasting for a good while. He's written a couple of books around best practices and collaborates with some really interesting people in the industry.

What advice would you have for someone who is interested in starting a career in speciality coffee?

Some roasters offer internships or apprenticeships but there's no one clear cut path to becoming a coffee roaster. Personally, I started in the cafe pulling shots and after a bit talked my way into packing bags in the roastery then hung around long enough to learn a bit about roasting. I also came with a background of Physics at University level, so I guess that gave me a natural advantage in terms of understanding the data and scientific processes that go into coffee roasting. I'd also recommend going to as many public cuppings as possible, although admittedly this is nigh on impossible at the moment. Showing enthusiasm is key to getting anywhere in life. If you're interested and willing you'll learn incredibly useful things from people.

What roaster(s) do you use at Machina Coffee?

We currently roast on a Probat P12 Mk2.

What is your favourite method of brewing coffee?

I would probably say the Kalita at a push. I find the Kalita seems to create less bypass of water round the edge of the filter and therefore I can push the grind finer and create more extraction.

What coffee(s) are you drinking at the moment?

Worka Wuri, from Ethiopia, from our limited-edition premium coffees range. It’s such an interesting coffee to drink and a total experience. It’s a banana process coffee, which is a version of natural anaerobic where the beans are sealed in a tank with strips of banana for over 10 hours. The result is a super fun, crazy coffee with notes of citra hops, pineapple and grenadine.

The other one I’m loving is Adriana Franco, one of our most recent filter coffee releases. It’s a washed, Pink Bourbon from Colombia. It’s a totally delicious morning coffee, tasty and sweet and I love it.

Obviously a totally biased answer but what can I say….

You can find out more about Machina Coffee on their website at machina-coffee.com or on their Instagram page @machinacoffee.