roasting coffee at home

Sometimes I feel like Robinson Crusoe in that I try to do everything myself. When I started to get serious about preparing good cups of coffee I didn't think that I would ever bother to roast my own coffee. I invested in semi-commercial espresso machine and grinder. I was buying craft roasted coffee typically for between $12.50 to $16.00 a pound a few years ago. Out of curiosity I order one half pound of green coffee together with my usually supply of espresso roast. The bag of green coffee was left on the shelf for a long time.
A couple of years ago, the price of coffee spiked due to worldwide coffee crops suffered from low yield due to natural impact to the crops. The price increase crossed the threshold what I willing to pay for a pound of craft coffee bean. The event triggered my curiosity in the art of coffee roasting. I pulled out my 1/2 pound bad of green coffee nearly forgotten in the pantry. Without putting much thought on the roasting process, I tried roasting a small batch in a cast iron pan. Needless to say the result was less than stellar. The roasted coffee was so uneven. The beans were burnt on the outside and very green inside. Some beans were badly burnt while others still very under roasted. No big loss, it was what I was expecting and I gained a lot of insight into what happen to coffee when you apply heat to them. I didn't want to invest in even a cheap stove-top popcorn roaster but just what to see what would happen to the green coffee beans by heating them in a cast iron pan.

In this brief and crude experiment I gained a few insights which helped form the foundation of my low cost and yet pragmatic home roast setup. I knew I need to set up a oven-like contraption to keep the roast temperature even while allowing the moisture to escape under a controlled fashion. I also need to have a mean to agitate the beans so they are more the less uniformly expose to the dry heat. I went and found my thick Calphalon aluminum sauce pan.

this is a older US made Calphalon  sauce pan - it's thickness and the well engage lid makes it ideal for stove top roasting

these is my roasting equipment

I have been roasting my own coffee for may be two years now. I must have processed about 100 lbs of coffee. Like culinary skills roasting coffee is a long pursuit. With each batch I roasted I leant.

Even purchase in a 20 lb bag, green coffee cost more than than the roasted Starbucks coffee beans you can pick up at Costco. Why, you ask. A lot of ink had been spilled on Starbucks' support of fair trade coffee. If you dig deeper, you would find that most heavyweights in the coffee industry that claim to support fair trade (or other similar initiatives that are supposed to bring better living to the indigenous bean growers) fall way short. Out of millions of pound of coffee they sold, only a minuscule percentage are fair trade beans. If you can pick up Starbuck's roasted bean at Costco for less than $5/pound and yet I pay $5.50/pound for a 20-pound green beans you can infer how much Starbuck pay the indigenous coffee farmers.

while I don't believe they buy all the coffee beans with fair trade arrangements I have no doubt Sweet Maria does more than any big companies

I roast coffee outside; the gloves help my hands withstand the heat as the sauce pan and lid get very hot towards the end of the process

I typically roast about 3/4 pound at a time and the process takes about 25 minutes and during that time I have to constantly toss the beans while keeping the lid on. It is a two hand process. The method let the sauce pan acts as a roasting oven. I have to open the lid a crack to allow the steam vapour to escape from time to time, as well to regulate the roast temperature.

once the roasting is in progress I cannot pause to take a photo as the batch can easily be ruined - here is what the beans looks like about 15 minutes into the process

I use the stainless steel sieve to toss the roasted bean in front of a electric fan to blow away the skins and to cool the roasted coffee

there are a lot of variables in coffee roasting and it is really fun to taste the different result - i kept this batch relatively lighter than I normally prefer

So why not buy a small roasting machine? I have investigated a range of consumer grade machines for home roasters. They ranges from from a few hundred dollars to about $1500. The problem I see with these machines is they are not built for the long haul. Most fall short in dealing with the build up of coffee oil.soot. To me I regard them as "toy" roasters.

Roasting coffee generate a lot of smoke and for home roasters the best option is to roast outdoors. For me if I were to purchase a roasting machine, the least expensive one is a sample roaster. A sample roaster is a commercial equipment design for test roasting small batches of coffee. They typically roast around 2 pounds at a time. Problem is a good sample roaster cost close to ten thousand dollars unless you are lucky to find a used one.