The Blog (archived)

Category: Coffee

Mobile Coffee Roasting With A Breadmaker

Thursday, November 12, 2009

I hereby reveal my latest development in the home roasting of coffee beans - a breadmaker and heat gun roaster mounted on a trolley for easy setup and storage.

Previously, I roasted coffee beans with just a bowl, a wooden spoon, and a heat gun mounted on a tripod. A heat gun is like an industrial strength hairdryer, blowing out there at 600C, and it worked very well. It all dismantled and fit into a crate for easy storage indoors, the only disadvantage being the time required to set it up and pack it away.

Mobile coffee roaster in storage mode
1. In storage mode

Recently I progressed to using a bread maker to house and stir the beans - much easier, with greater temperature control and more evenly roasted beans. The only problem was that it didn’t all fit into a crate, and taking all the bits outside and setting up, then later dismantling and storing, took longer than the roasting itself. Because of the smoke and chaff produced when roasting coffee it needs to be done outside, but I don’t have anywhere outside suitable for storing the gear, so the obvious solution was to build some sort of mobile arrangement. These photos show what I came up with (click on any of them to see larger versions).

The first photo shows my coffee roaster in storage mode, as it is when kept indoors. Built onto a box-moving trolley is a wooden platform holding the bread maker, a heat gun mounted on the centre column of a tripod, and the fold-down cooling platform (the toilet seat). Stored with this are the other necessary bits - cooling tray, power board, extension cable, multi-meter with temperature probe, stopwatch, oven glove, wooden spoon, fold up stool, and a sweat band (it can get hot when roasting). The only thing not housed on the trolley is the fan: that’s because it gets used elsewhere for other things.

Roasting in progress
2. Roasting in progress

The second photo is roasting mode, seen here inside my garage. Hot air from the heat gun blows onto the beans being agitated inside the bread maker, with the bean temperature being measured by a probe inserted into the side. Temperature is adjusted by moving the heat gun up and down. The fan reduces the stress on the heat gun element while also blowing away some of the chaff.

The third photo shows cooling mode. Once the beans are done, the fan is laid down on its back, a mesh cooling tray is placed on top of the fan, and the hot beans are poured onto the cooling tray. It only takes a minute for the air blowing upwards through the beans to cool them down completely. After the removal of the beans and a quick bit of unplugging and folding up, the contraption is ready to be wheeled back indoors until next time.

Beans being cooled
3. Beans being cooled

Why the toilet seat, you may ask? I needed some method of supporting the fan in its laying down position - something to keep it up off the ground to allow good airflow, with plenty of open space in the middle where the fan draws up the air. A toilet seat performs this function perfectly, without modification. It even came with its own built-in hinge so it could be folded up for storage … and being a guy, leaving the seat up comes naturally to me.

Apart from the bread maker (which I picked up second-hand from a pawn shop), I didn’t need to spend anything on this mobile coffee roaster. I already had the trolley, the bits of wood and other parts, and the toilet seat was been sitting around for at least 10 years waiting for another chance at life. It all supports my belief that nothing potentially useful should be thrown away in case it might be useful one day.


Coffee Roasting Ups And Downs

Wednesday, March 4, 2009

In 2007 I blogged here about how I’d begun roasting my own coffee beans using a popcorn popper, and shortly after I reported on an improved method using a heat gun and bowl. Things have progressed a little, so I thought I’d do an update on the steps forwards, and backwards, and the lessons.

Ready to roast: raw beans in the bowl
Ready to roast using my current
setup: raw beans in the bowl

The setup was simple - a heat gun, mounted on a tripod, blowing super hot air (600C) into a stainless steel bowl, with the beans being stirred by hand with a wooden spoon. Heating is adjusted by moving the heat gun towards or away from the beans (hence the tripod). It produced some great tasting beans, but with some drawbacks. One was the stirring by hand, which can feel a little tedious when done for 15 minutes at a time. Another was the way the bean temperature fluctuated in windy weather - the wideness and shallowness of the bowl left the beans susceptible to the cooling effect of wind gusts.

No problem, I thought. I built a motorised stirrer, and switched to a tall and narrow tin to shelter the beans more. Unfortunately it didn’t work. The tin shape might have reduced the influence of wind a little, but I couldn’t get the stirring to work properly. I experimented with different stirring speeds and paddle designs, but couldn’t get the motorised stirrer to mix the beans thoroughly enough. The result was unevenly roasted beans - some underdone, some almost charcoal, and few in between. Not nice!

So I went back to the wide open bowl and the wooden spoon, and came to appreciate just how well it worked. Stirring for 15 minutes once per week isn’t that hard really, and does allow for very thorough mixing. As for temperature fluctuations, I just took more care to avoid roasting in the wind.

I also tried being more scientific about temperature control. Instead of just observing the bean temperature readout, I set up a laptop and entered the numbers into a spreadsheet while roasting to produce a live chart of the temperature profile, which I could try to match with that of previous good roasts. This proved distracting, and more trouble than it was worth, so I went back to calculating the desired heating rates in my head.

After the roast: beans cooling
After the roast: beans cooling

One worthy improvement was the use of a fan (see photos). While roasting, the fan provides cool air for the heat gun intake, which prolongs the life of the element. It also blows away the chaff which the beans eject when they crack open. After roasting, the fan is laid on its back so that it blows upwards: this rapidly cools the beans when they are spread over a mesh screen above the fan.

It seems somehow ironic that, after trying to improve the roasting process with technology and a motor, returning to the low-tech simplicity of the heat gun, bowl and spoon has worked better. Apart from a basic temperature display (I need some measure of how fast it is rising), I roast coffee by sight, sound and smell, and the results keep getting better as I get to know each bean type’s characteristics. Equipment and gadgetry are appropriate for big commercial roasters, but human senses and experience are sometimes all the home hobbyist really needs.


Another Benefit Of Drinking Coffee

Wednesday, October 8, 2008

Like other coffee enthusiasts, I see many pleasures and benefits in drinking quality coffee. Now I can claim another one, although in this case it’s other people who benefit from this drinking habit.

I buy green (raw) coffee beans through an Australian website known as CoffeeSnobs, and roast them myself. Last year Andy Freeman, the guy who runs the site, started a scheme whereby fifty cents from every kilogram of beans sold goes into a fund he calls “Fair Crack”. The idea is that whenever enough money builds up, it is spent on projects which directly benefit small growers of specialty coffee.

It’s a way for coffee enthusiasts to give something back to the growers of the coffee, who only get a small cut of the final price and sometimes struggle to survive. CoffeeSnobs members have overwhelmingly embraced the idea.

Tanzanian coffee growers
One of the CoffeeSnobs pulpers will be used
in this building in Njari-Rononi, Tanzania.
Outside are some of the 68 coffee growers
who will use it. Photo: Bente Luther-Medoch.

The first project has recently been announced (full details here), and the beneficiaries are small coffee farmers near the southern slopes of Mt Kilimanjaro in Tanzania. Two villages will each be provided with a pulping machine - processing equipment they would probably not have been able to access otherwise. Shared by all the independant farmers in the area, these will enable them to take a superior grade of bean to market and receive a higher price. Scales and fermentation tanks are also being provided for communal use.

There are a number of things to like about this:

  • Farmers should get a higher price for their beans, making their businesses more viable.
  • 68 farmers will be helped by the pulper in one of the villages. This also benefits their families, and their communities.
  • It contributes to the growth of the specialty coffee industry in Tanzania.
  • Admin costs are zero: 100% of the funds hit the ground in Tanzania

Although the money comes from the purchases of CoffeeSnobs members, it is by no means a sacrifice:

  • The contributions per kilo of beans are small change for us, and hardly noticed.
  • Even with the contributions, buying green beans this way cost only about one quarter of the price of equivalent commercially roasted beans.
  • We get to enjoy superb coffee, roasted just how we like it, as fresh as you can get.

It almost sounds too good to be true, but it IS true. It’s great to know that win-win situations like this can really happen. I’m also encouraged that the business world contains people like Andy Freeman of CoffeeSnobs, who not only runs an excellent business, but uses it to do something good for others.

By a small coincidence, I happened to be drinking a Tanzanian coffee when I read about this project to assist Tanzanian growers. My coffee was from a different area, but who knows - some day I might get to drink coffee which passed through the pulper my purchases helped (very slightly) to fund. The thought adds an extra level of enjoyment to my coffee drinking habit … and makes me want to buy more coffee.


Good Coffee In Hobart

Monday, July 28, 2008

If you’re addicted to good coffee, and you’re on holiday, then it follows that you’ll want to search for sources of good coffee wherever you travel to. That was the case with me recently - in search of the best coffee in Hobart.

Obviously I couldn’t sample every coffee outlet in Tasmania’s capital city, so I visited the CoffeeSnobs website to draw up a short list. One forum discussion (first page starts here) is devoted to recommendations of good cafes in Tasmania, and as most of the contributors know more about coffee than I do - and live in Tasmania - I used their top choices as my starting point.

When it fitted in with other activities, I hit the streets of Hobart to sample an espresso at the most recommended cafes (plus a couple of others), and in some cases a double shot latte as well. My opinion is that of an amateur enthusiast, not an experienced expert, and I haven’t yet come to grips with describing body, aftertastes, and subtle flavour nuances like wine buffs do - but I can appreciate quality. The search for it was rather enjoyable!

Inside Villino Espresso in HobartOne cafe’s coffee stood out for me - Villino Espresso, at 30 Criterion St Hobart, near the city centre. The owners, Richard and Melissa, are passionate about producing excellent coffee. With their La Marzocco machine, Mazzer grinder, good fresh beans and much skill and dedication, the result is consistenty good (I tried it on several occasions just to be sure).

The espresso and double ristretto I had were rich, syrupy and flavourful without any bitterness, and the milky coffees were also worth going out of your way for. I felt no need for sugar in any of them; always a good sign for someone accustomed to always having sugar with coffee.

If you’re a coffee enthusiast visiting Hobart, sampling all the cafes recommended by the users of the CoffeeSnobs website would be a pleasant mission. But if you haven’t got time for that, heading straight for Villino Espresso is unlikely to disappoint.


Home Coffee Roasting - A Better Way

Monday, January 14, 2008

Some time ago I began roasting raw coffee beans in a popcorn popper. It didn’t take long for the limitations of this method to become apparent, and so I’ve progressed to an improved method using a tripod-mounted heat gun, which I hereby reveal.

I blogged about my popcorn popper roasting setup (see "Confessions Of A Coffee Snob"), which gave reasonable results in cool weather. However, in warmer weather the roasting process happens too quickly to allow the full flavour of the beans to develop, and the popper’s heat can’t easily be adjusted. Another method was needed, which would allow slower roasts during the long hot Perth summer.

Tripod-mounted heat gun and bowl coffee roasterA lot of great information on home coffee roasting is available on the CoffeeSnobs website, and Sweet Maria’s has an inspiring illustrated collection of home-made roasting devices. With ideas from these, I built the tripod-mounted heat gun and bowl roaster shown in the photo.

It’s basically just a heat gun - normally used for drying or stripping paint - pointing into a stainless steel bowl, with the beans stirred by hand with a wooden spoon. A motorised stirrer could be added … but that’s another project. The tripod mount allows the heat gun to be positioned in just the right spot, which is how the temperature in the bowl is controlled (as measured using a multimeter). Also the setup is easily moved around, and dismantled for storage.

This is a manual, hands-on and low-tech method of roasting coffee beans, but the degree of control means much more of the bean’s potential can be realised. By adjusting the height of the gun to slow the rate of temperature increase, a roast can be extended to 15-18 minutes instead of the 5 or 6 minutes it would take in a popcorn popper on a warm day. The slower roasting leads to better flavour in the cup, not to mention the satisfaction (and money savings) of doing it yourself.

It makes me wonder what else can be achieved at low cost by tinkering with household bits and pieces.


Confessions Of A Coffee Snob

Tuesday, September 11, 2007

I’ve always enjoyed drinking good coffee, and trying to get the best from my espresso machine. However, I’ve recently climbed to new heights of coffee snobbery, becoming a signed up member of the CoffeeSnobs website, and started roasting my own beans at home.

A beginners home coffee roasting setupRoasting green (raw) coffee beans is a lot easier and more accessible than you might think. The photo here shows the simplicity of my beginners setup. Sitting on a crate is the main tool - a popcorn popper - with the addition of a soup tin chimney so the beans don’t pop out. Near it are a metal sieve and colander (for cooling the beans after roasting), oven gloves (the popper gets very hot!), a clock for timing the process, and some green beans in plastic bags. The crate is not necessary, but is handy for ventilation under the popper and for storing the stuff in. The only part I didn’t already have was the popper - costing only $20, this wasn’t much of a barrier to home roasting.

I won’t go into detail about the process, which is described very well in “A beginners guide to roasting using a popper” on the CoffeeSnobs website. Generally less than 8 minutes plus cooling time is all it takes, and a wonderful aroma wafts far and wide. A lot of chaff and some smoke also wafts far and wide, which is why it’s best done outdoors.

Easy, right? Yes … well sort-of. Roasting beans is easy, but getting them to taste their best takes practice. The optimum degree of roasting varies with the individual popper, the ambient temperature and humidity, the amount of beans used, and personal taste. Different beans will also prefer different roasts, varying according to country, plantation, and crop. You’ll need to try different roast times, compare results, and make notes for future reference - lots of trial and error. Yes, there will be errors! But with green beans costing as little as one third or one quarter of the price of commercially roasted coffee, a lot of money can be saved, even with a few mistakes.

Straight from the roaster!For me this chance to experiment is part of the fun. It’s only a matter of time before I add a thermometer to the setup, and some method of slowing the speed of the roast to improve flavour development - all of which appeals to those like me who have scientific curiosity and do-it-yourself urges.

Why do it, other than the satisfaction? Because using freshly roasted beans at their flavour peak, ground using a decent grinder just before brewing, has the potential to make truly fantastic coffee … better than that found in most cafes, if all variables come together. The quest to reach this potential is why many coffee snobs roast beans at home. Even when the coffee isn’t as good as it could be, it’s still pretty good, and cheaper. I can think of worse things to be than a coffee snob!


Inspired By Coffee Excellence

Monday, May 7, 2007

When someone takes pride in their work and does something really well, it can be an inspiration to others. I found this to be true recently at Epic Espresso in West Perth (Western Australia).

Originally I went there for some of their beans to try out at home, but the glorious aroma of fresh coffee enticed me to sample one of their drinks immediately. It was exquisite! I read their brochure/menu and learned just how seriously they take their coffee, and why it is so good.

A long macchiato at Epic EspressoThey use their own custom blend of fresh, locally roasted beans, as well as filtered water and the best milk. The espresso machines are gorgeous, hand-crafted and state of the art - there are only a few hundred in the world as good. Naturally the grinders are of the highest quality, and even the cups are of a high standard to maximise heat retention.

In keeping with the tools and ingredients, the staff are all highly trained to world barista champion level. In fact one is the 2006 WA Barista Champion, and another is the 2006 WA Latte Art Champion. The owner, Corey Diamond, was trained by the 2003 World Barista Champion (also an Aussie, by the way) and is an accredited coffee judge. His mission for Epic Espresso is “to raise espresso coffee to an art form” and “be the state’s leading authority on espresso coffee”. In other words, they really know what they’re doing, and they strive to do it well.

The payoff for customers is fantastic coffee. I’ve always drunk coffee with sugar, but Epic Espresso is the first place I’ve truly enjoyed it without. Their espresso was the best I’ve had, as was the long macchiato (pictured). And the ristretto … awesome! What this drink lacks in size (the cup wouldn’t look out of place in a doll’s house) it makes up for in quality and intensity - I could still taste it three hours later.

I took some of their beans home with the aim of improving my own coffee creations. With my comparitively humble equipment I can’t expect to match what is served at Epic Espresso - but experiencing the excellence of coffee done really well has inspired me to have a go.

Note: Some bloggers write paid or sponsored reviews; I don’t. The above is my own opinion.