Batch 412: slowing the Guji down

The new Guji arrived the last week of September, and the first test roast was a disappointment. Sweet at the front, then a sharp, almost vegetal edge at the back of the tongue. We have tasted that edge before. It usually means the bean was pushed too hard in the first half of the roast and the inside never caught up with the outside.

So for batch 412 we did what we always do in that situation: nothing clever. We lowered the charge temperature by six degrees, kept the gas at the same setting for longer, and let the drum run slower through the drying phase. Yellowing came about thirty seconds later than before. First crack came at 9:10 instead of 8:20, and we dropped the beans 2 minutes and 10 seconds after.

The difference showed up on the cupping table the next morning. The vegetal note was gone. The blueberry came forward, and the jasmine that the importer promised appeared once the cup cooled below 50 degrees. It is a small change on paper, a little under a minute across the whole roast, but you can taste it.

What we write down

Every roast gets a line in the log: charge temperature, turning point, first crack, drop time, colour reading, and a sentence of tasting notes the next day. We are not precious about the numbers. They are there so that in January, when somebody asks why the Guji tasted better in October, we can answer without guessing.

The Guji lot is now on the shop page as a 250 g bag. We roast it on Tuesdays, and the bags that go out on Thursday are the ones we like best, because by then the coffee has rested for two days.