I wanted to write an article on tipping and scorching but when it came down to it, I realized we already covered this bit so we won't go into too much detail.
A quick refresher. Scorching is the ashy dull taste visually indicated by a dark line in the bean. Tipping is a funny little black ashy mark on the end of the bean alluding to much the same off flavor.
Why does it happen?
Too fast, too much drying, uneven roasts, and cooling problems to name a few.
How do you fix it?
Know your roaster and the physics behind it. Use that to your advantage or change what part is holding you back.
In terms of roaster errors, baking is most interesting because it's quite common. Bakey in it's worst is this horrible flavor that dulls out everything in your coffee. It's like a cardboard flavored cake. Not really acidity or bile sour but like an intense gassy sour flavor. Baking is often stated as simply too slow. Well it's not exactly too slow, but if you want more detail, pay me to teach you. Ha, you thought this site was all idealistic and free info for everyone.
That's not really the point though. If you don't know what a bakey coffee tastes like or a tipped/scorched roast flavor/appearance, as a barista, how good are you really? A roaster who consistently has this problem has no legit excuses but should a great barista understand those flavors when they appear? I used to think I knew my stuff but there were days I really could not pull a good shot. It wasn't until I stepped out from the bar and really began to learn more that I began to expand my palate and because of the frustrations with a local roaster's inconsistencies that we were almost forced to roast. If you want a good cup, control it all from start to end, right?
Sounds simple but it's hard.
In fact, it sucked. It really really sucked. I can't put enough emphasis on how bad it was. I think we roasted more than 40lbs 250g at a time before we had a few drinkable roasts. Green, astringent, acrid, scorched, baked, flat, baggy, moldy, you name it, it was all swill at first. We tried profiles being floated by pundits and internet personalities, we did a little 'research' on roasters we knew to understand their approach. In the end, we found flaws in many and completely disregarded others going in our own direction.
Because every machine is different.
We had to learn our machine inside and out, make big changes and then keep roasting because roasting is very machine dependant and so many internal/external variables can affect a roast. Do we feel any closer to perfection, ask me after another 100lbs of sample roasts, but at least our mistakes and research are drinkable now and I am happy with the sweetness though it might need a little more 'Technicolor.' I dare not mention how much we have spent on green or the hours toiled behind a roaster tasting and making gut decisions about what went wrong. Most of the time, only two of us in an 85 degree room with tempers flaring and nothing to show for it.
Will I write much more about roasting on the site, no, not in much detail anyway. My cups are pleasant enough that I have nothing to complain about so I will leave you with this.
Scorching, tipping, and baking....
Don't do it and don't put up with it from your roaster either.