Trying a new coffee part 1: Roasting

Tue, 28/08/2007 - 13:11 -- James Oakley

Well, the Sulotco is here. Here they are:

Green Sulotco Sulawesi Coffee Beans

As you can see – excellent quality bean preparation. It’s time to roast those beans. Not much happens to start with. They start off the mid-green colour you see above, and gradually turn a yellow-ish colour. At this stage they just smell damp, a bit like drying hay. Then, they start to turn yellow-brown and then pale brown. At this point the smells change to roasting grain / toast. After 10 minutes roasting, here’s the colour the beans have got to.

The beans after 10 minutes

We keep going until (on this occasion) 17 minutes 15 seconds, when the first pops of “1st crack” were heard. “1st crack” happens when the bean mass is about 400 degrees Farenheit and the cellular structure of the bean changes. The result is a series of distinct loud pops, a bit like corn popping. By this stage, they are a more familiar brown colour:

The beans at 1st crack

1st crack continued until 18:30. Often you then get a gap of up to several minutes, during which time the beans continue to darken and to swell in size. On this occasion there was no gap – as 1st crack finished the first pops of “2nd crack” began. 2nd crack is more like 450 degrees Farenheit, and sounds like Rice Crispies in milk – lots and lots of softer popping sounds. Many coffees you woulodn’t want to take as dark as the start of 2nd crack, but as I said in my previous post Indonesians can handle it – indeed, they require it to get the best out of them.

I allowed 2nd crack a full minute to run – until the pops were well established and I could just begin to see a bit of oil showing on the surface of some of the beans. Then I dumped the beans into the cooling tray. And there we are… the finished product.

Roasted beans in the cooling tray

By this time, they have swollen in size considerably. Compare the size of the green beans to some of the roasted ones.

Different bean sizes

These are now ready to be ground, brewed and drunk. But freshly roasted beans still have a lot of CO 2 in them, so they are best allowed to rest and “degas” for a few days first. I’ll give them 24 hours and then see what they’re like. More later…

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