Roasting Techniques by Jazzy Jeff

Tonloads of Barista information online, but not so many for coffee roasters.
Our main coffee roaster Jeff thought it was a good idea bringing out some of his roasting experiences.
This following article is his :

Roasting experiments:

Folowing the lack of information there is about roasting and profiles I decided to put my findings
online to usher in some discussion. Why not be more transparent about this? As an experiment I
took one main component of the house blend: Peru Altomayo. We roasted these full batches on 3
profiles, tasted 6 days after roast on espresso, all on the same grind (ditting 2-) same machine (linea),
same temp, same dose (22 grams, 2 shots) all roasted on our Giesen roaster:

Fast cat:

-a fast ramp up with high fan speed (45pct) with a pause in heating the drum on 10.30 minutes @
166c

-1st crack at approx 11.30 @171c

-Shortly after the middle of the 1st crack, heat back on and developing time for 3.3minutes

-Drop a few seconds after 2nd crack at 15.30 min @ 193c

Result: fresh and lively acidity (apples), butterscotch, clean finish, maybe thinner body

Normal cat:

-slower ramp up with lower fan speed (40pct) with a pause in heating the drum for 2 minutes going
in to 1st crack on 11.10 @ 166c

-1st crack at approx. 12 @172c

-Shortly after the middle of the 1st crack heat back on and developing time for 3.5 minutes

-Drop after a few seconds after 2nd crack at about 16.10 min @ 193c

Result: Dull but sweet, remarkably less acidity but bigger body, a bit of dried fruits (figs).

Slow cat:

-Even slower ramp up with back valve full open, fan speed at 35pct, same pause in the flame on
11.50 @ the same temp of 166c

-1st crack at apporx. 12.40 @ 172c

-Shortly after the middle of the 1st crack heat back on and developing time for 4 minutes

-Drop after a few seconds (low sound 2nd crack) at about 16.50 min @ 194c

Result: Creamy, almost no acidity, sweeter, but bitter ashy notes, maybe some tobacco, classical

We tested these shots with the people in the bar that Sunday, Roeland included, and 4/5 liked the
fast cat. 1/5 liked the slow cat, a classical tongue.

I noticed also that a faster roasted coffee will be lighter and will benefit from a few more days resting

to control the acidity a bit, a longer darker roast will be drinkable sooner but drop also faster in
quality due to oils being more exposed to oxidation.

Jazzy Jeff