Popper roasting in a humid climate - beans going dark too fast

rina_preanger

Hello from Bogor, West Java. I have been roasting at home for about a year, first in a wok and now in a secondhand popcorn popper with the lid cut down so the chaff can get out. Mostly local Preanger beans that I buy green from a small farm near Pangalengan, 1 kg at a time.

The thing I keep fighting is humidity. Green beans here sit at around 80 percent humidity most of the year, and I am not sure if that is why my roasts go from first crack to too dark so fast. Batches are 90 to 100 g, first crack comes at about 5 minutes and I pull at 6 to 6:30. The cup is fine black but tastes a bit flat through the V60.

Do people in humid places dry their green beans before roasting, or store them differently? Any tips on slowing the popper down without killing the fan would be good too.

rina_preanger

Quick update on the popper batches. I started stopping the roast about 30 seconds after first crack instead of waiting for it to finish, and spreading the beans on a metal tray in front of a fan. In this humidity they still darken a bit after, but much less than before.

The test that convinced me was a flask. On match nights at Pakansari the kick-off is usually late evening (the times are on https://garudayaksa-fc.id/), so I fill a thermos at home around six and drink it in the stand a few hours later. The darker batches went flat and bitter by half time, the lighter ones were still fine.

So for now I'm roasting lighter on purpose and resting the beans three days in a jar with a one-way valve. Next experiment is the same beans as a V60 at 92 degrees instead of just off the boil.