第十八课 - This and That

Transcript

So I want to show you very quickly what happens to coffee as it's roasted. This is green coffee. Coffee is the seed from the fruit of a flowering tree. It's dried, it's processed and dried in its skin and it becomes a very dense green bean. It's not really a bean, it's a seed, but we'll call it a bean as everyone does.

As you start to roast the coffee, it goes from that to a slightly pale white color. What's on the outside here is chaff. That's also called siver skin and it comes off during roasting.

The next stage: So it's turning pale at about 2 to 3 minutes into roasting. Some roasting is a little bit faster in a roaster. Now we have a kind of tan or orange stage where it's definitely losing some heat and losing some moisture content. The coffee's becoming a little bit lighter, moves around a little quicker in the roaster.

And this is the tan stage. This is very slow this early develoment from the green to the tan. You know in some roasters that could be ten minutes of development until you hit the first crack. So still quite a light-colored coffee. Not what you'd want to drink. It's very grainy if you drink it.

Here we're approaching first-crack, which could like I said happen anywhere from in a real fast roaster, several minutes, in a drum roaster maybe as long as ten or twelve minutes. And you see this very highly varied surface texture, this pale silver skin chaff in there. Now here's where we've actually gotten to coffee that could be consumed. This, you could drink this coffee. This coffee has gone through first crack so there's been this audible popping sound in the roster and that's kind of your clue. Once that finishes, the popping, that coffee is gone through first crack. We call this city roast. It's a lighter roast, and looking under the stong light you see that dark dark surface texture. But this could bee a very good roast for coffee you want to be a bright lively cup.

This is a little bit more roasted, but if you notice that this bean is puffed up a little bit more. It's opened up that crease. It's not quite so flat on this side. The silver skin's a little darker, so that's a city plus roast. We call this city plus two.