In a prior article, I spent a little time talking about coffee, where it comes from, the various types and left off at the point that the green beans were now ready to be shipped. If you wish to read that article it is called Coffee – the basics.
That is great as far as it goes – but now you ask, what the heck should I do now.
Well, the answer to that is simple – roast it, grind it, brew it and enjoy nirvana.
First – roasting.
Freshness is a huge issue with store-bought coffee since the quality of the coffee declines quickly after roasting. After 5 days the aromatics of the coffee are fading, and after 10 days there is a drop in overall cup quality. When you roast your own your coffee is always fresh. Lord knows how old the big-brand coffees sold in supermarkets and cafes actually is. Also home roasting lets you control the roast level, so you can customize the coffee to your liking, as well as choose from a vast array of green coffees. Green coffee, unlike roasted, is quite stable and will not have a drop in cup quality from about 6 months up to 1 year from arrival date
Roasting coffee is a little like popping popcorn. Most of the home coffee roasters out there work in a similar way to an electric hot air popcorn popper in that they blow hot air through the green coffee beans and heat them up. Some use the air being blown through the coffee to stir it up and ensure an even roast, some have drums to ensure an even roast. The larger commercial units pretty much all use a drum. The difference is in the consistency of the roast, with the drum roasters being more even. Irrespective, The coffee slowly roasts and just like a popcorn, the bean changes as it gets cooked.
Understanding the different stages of the roast will help you control the flavor of your cup and appreciate how different roasts result in different cup flavors.
Yellowing: For the first few minutes the bean remains greenish, then turn lighter yellowish and emit a grassy smell.
Steam: The beans start to steam as their internal water content dissipates.
First Crack: The steam becomes fragrant. Soon you will hear the “first crack,” an audible cracking sound as the real roasting starts to occur: sugars begin to caramelize, bound-up water escapes, the structure of the bean breaks down and oils migrate from their little pockets outward.
First Roasted Stage: After the first crack, the roast can be considered complete any time according to your taste. The cracking is an audible cue, and, along with sight and smell, tells you what stage the roast is at. This is what is call a City roast.
Caramelization: Caramelization continues, oils migrate, and the bean expands in size as the roast becomes dark. As the roast progresses, this is a City + roast. I hardly ever go past this point. When you are the verge of second crack, that is a Full City roast. The bean is now a dark brown, but doesn’t look oily
Second Crack: At this point a “second crack” can be heard, often more volatile than the first. The roast character starts to eclipse the origin character of the beans at this point and is also known as a Vienna roast. A few pops into second crack is a Full City + roast. Roasting all the way through second crack may result in small pieces of bean being blown away like shrapnel!
Darkening Roast: As the roast becomes very dark, the smoke is more pungent as sugars burn completely, and the bean structure breaks down more and more. As the end of second crack approaches you will achieve a French roast. The beans tend to look black and oily. This is what a lot of people consider an espresso roast, but as I’ll cover in another article, this simply isn’t true, and you have MUCH more options with espresso than that.
That deals with the process – basically you heat the beans up and stop when you reach the color you want. This is where internet research comes into play, as each type of bean changes its taste depending upon where you stop the roast. My favorite coffee, Ethiopian Yirgacheffee has very different flavors depending upon where you stop the roast and I like it just after first crack, even when I use it for espresso.
So you can either use color or sound to determine where to stop your roast. Now lets talk process and tools. What I use is a popcorn popper, that I bought for $15 and a couple of bowls. I run the popcorn popper in the kitchen under the exhaust hood and the chaff that gets blown off the bean goes into a large metal bowl. Don’t use a small bowl as the air from the popper will blow the chaff out as it is very light and you will make a heck of a mess. As part of the roasting process, especially if you like darker roasts, there will be smoke, so that is why it is done under the exhaust hood.
Once your beans have achieved the state of roast that you want – then tip them into a colander, give them a bit of a shake to get some of the remaining chaff off, and leave them to cool. If it is winter, then by an open window works great, if it is summer, the same thing works, but stop your roast a little earlier as the beans don’t cool down as quickly and do continue to cook a little.
Once the beans are nice and cool, then give them another shake, or rub them between your hands to remove the remaining chaff, and you are ready to go. The experts say that you shouldn’t use coffee for about 4 hours after it has been roasted, as it is still outgassing. You can see this – if you seal your newly roasted coffee into a jar with a relatively loose lid immediately after roasting, the lid will get blown off at some point. What I do is simply leave the beans to cool/outgass for a few hours and then seal them into a jar.
There you have it, your first batch of roasted coffee. It is easy, simple and cheap, and fits the subject as it is truly sublime.