back off, man, i'm a scientist

all righty. so. i wanted to start up a very detailed coffee roasting + tasting log so that i can keep track of which beans and roast levels i like and thus introduce a little more consistency and sanity into my procurement processes.

or something.

anyhow, so i tackled the technical problems and got the db and web interface up and running, though not polished. more on that later. somewhere along the way i realized that one of the most important terms for describing coffee flavor is "acidity". here's what Tom has to say about it:

"Acidity. Acidity in relation to taste has nothing to do with acidity in terms of the gnawing pain in your stomach. Acidity in coffee might be described by terms like bright, clear, snappy, dry, clean, winey, etc. Coffees without acidity tend to taste flat and dull, like flat soda. Acidity is to coffee what dryness is to wine. Different varietals s will possess different kinds of acidity, like the wine like high notes of some African coffees versus the crisp clear notes of high grown coffees from the Americas. Unpleasant acidy flavors may register as sourness. Dark roasts tend to flatten out acidity. This is a key term in coffee tasting!"

Got that? Key term in coffee tasting! Only one problem: I've been home roasting for ages now and although I know that Kenyans are sposedly more acidy than Malabars, I couldn't really say with confidence that I understood the concept of "acidity".

one thing i did know, though, is that the longer one roasts a bean, the less acidity is left in the bean.

so, i devised a simple experiment: take a single bean (a kenya estate peaberry, because kenyas are known to be high in acidity), roast it to City, Full City, and Vienna, and identify "acidity" as "that which is present in abundance in the City roast but pretty much gone in the Vienna roast".

Since I'd be roasting small amounts of beans, I brought Smokey (my Fresh Roast+ 8) out of the closet and tried to remember how to use him. I think I used too many beans (3.5oz) because it roasted way too fast -- less than 5 minutes to Vienna. No matter -- the roasts themselves are likely suboptimal, but the point of the experiment is to identify relative differences, so as long as the profile is consistent (if not optimal) I figured I'd be okay.

I figured right.

The differences between the roasts are dramatic.

The City roast is bright, fruity, sweet, floral, and full. Now, none of those terms mean anything to someone who doesn't understand them (i.e. me yesterday) but swing by some time and I'll show you what they mean. This was a truly fantastic cup and I think my roasts in the future (at least of Kenyas) will bear far away from second crack.

The Full City+ roast is caramelly, fuller bodied, syrupy, and retains a little of the floral brightness of the City roast. It was very easy to identify the "ah, this is the characteristic that was diminished" characteristic and declare same to be acidity. Although the cup was not as bright, it was still one of the better cups I've ever had.

The Vienna roast I underextracted, fearing it to be charcoally. It is a bit charcoally, but that's a result of my nearly-uncontrolled superfast roast. Still, it wasn't bad at all. Chocolatey, filled with spicy black-pepper, it had none of the brightness of the City. Again, this helps enormously in identifying the flavor I'm intending to ID. This was also a very good cup.

So, conclusions:

This particular bean is amazing, producing an excellent cup at all roast levels, even when roasted poorly.

Smokey might actually produce a better cup than the SC/TO roaster. I must attempt to speed up the SC/TO roasts (no problemo, I don't roast on max heat) and see how it is. Remembering back to previous roasts, I've gotten acidity from my beans but it's usually not so pleasant as the stuff I got with today's City roast. That may be on account of the particular beans used, but it may also be that my roast is too slow (or something else entirely).

I should stop roasting to Vienna. I knew that, but I kept forgetting. Just Say No!

I now know what "acidity" is and can proceed to populate my coffee database with accurate cup evaluations.

The peppery/spicy notes that I often notice in darker roasts are probably transmuted acidity.

Now i'm jittery and ready for a hike.