Home Roasting7 min read

How to Roast Swiss Water Decaf Brazil: F-NAT 0-1200 at 3.4

Data-backed case study for natural-process Swiss Water Decaf Brazil: medium chocolate-nutty goal and the F-NAT corridor that stuck.

BrewedLate Coffee

Coffee Expert

#decaf Brazil #Swiss Water Process #home coffee roasting #Kaffelogic #F-NAT 0-1200 #chocolate nutty #decaf roasting

The short answer: for Swiss Water Process Decaf Brazil (natural, Minas Gerais), the keep recipe is F-NAT 0-1200 at level 3.4 / 120g. Level 3.0 was only “decent” and still wanted more chocolate; stepping into the mid-3s on the same family is where the cup stuck — and where tasting notes quietly stopped because it was good.

Home roast case study
12 roasts · 2 profiles
Goal: chocolate-nutty

Brazil · Minas Gerais · Natural · 900-1200m ASL · NY 2/3 MTGB GC · John Burton

Aroma of chocolate, roasted nuts and dried fruits. Flavours of malted chocolate milk and nut brittle. Long Chocolate aftertaste. Low acidity and medium round body.

Dialed-in recipe
F-NAT 0-1200
Level 3.4·120g batch
“Settled after early “decent but want more chocolate” notes — F-NAT 0-1200 @ 3.4 / 120g is the keep recipe.”

Winning batch R-089 · 2026-06-30

Roast loss
0%
DTR
19.7%
ROR pre-FC
31.8°/m
ROR dev
8°/m

Cup quality across 12 attempts

Each point is a roast scored from tasting notes (1 = miss, 5 = dialed in). The series stops at the teal halo — once dialed in, later repeats aren’t scored the same way.

12345Cup qualityR-030R-050R-054R-074R-085R-089Roast attempt →

Where the good cups live

Roast level vs batch size. Color = profile family; larger dots = better cups. Notice how quality clusters once batch size moves to 100–120g.

1.522.533.5Roast level (higher = darker)40g60g80g100g120g140g160gBatch size
F-NAT 0-1200
NCT Filter D
○ size = cup quality

Roast mechanics that stuck

DTR, roast loss, and rate-of-rise across attempts with klog data. Each series is scaled on its own axis so shapes are comparable.

R-030R-050R-054R-074R-085R-089Each series scaled independently (shape, not absolute overlay)
DTR
Roast loss
ROR pre-FC
ROR development

What the data taught us

  1. 1First logged cup (R-030, F-NAT 0-1200 @ 3.0) was decent but needed more chocolate and less acidity.
  2. 2Stepping level up into the 3.3–3.6 band on the same F-NAT 0-1200 family is where the chocolate-nutty goal landed.
  3. 3Settled recipe: F-NAT 0-1200 at level 3.4 / 120g — repeated on R-089, R-100, R-102 with only light tweaks.
  4. 4Stopped writing cup notes once it was consistently good; later batches are confirmation roasts, not failures.
Roast goal: Develop through first crack to fully develop the inherent sugars and chocolate/nut notes without tipping into roast-driven ash. Aim for a smooth, sweet cup with malted chocolate and nut brittle prominently featured. The medium roast level will balance body development with sweetness while avoiding grassy underdevelopment or flat over-roasting.

Want to log a journey like this?

Track profiles, klog metrics, and tasting notes until the cup clicks.

Open roasting log

About this decaf

Swiss Water® decaf from Brazil’s coffee heartland: chocolate, roasted nuts, dried fruit, malted chocolate milk, nut brittle, long chocolate finish, low acidity, medium body. Roast goal: chocolate-nutty medium development — sugars and cocoa without grassy underdevelopment or ashy overdevelopment.

Kaffelogic reminder: higher level numbers are darker. 3.4 is darker than 3.0.

Journey

R-030: decent, not done

First detailed note at F-NAT 0-1200 @ 3.0 / 120g: decent cup, but more chocolate wanted and residual acidity to replace with sweetness.

Climb the level band, stay in family

Later batches stayed almost entirely on F-NAT 0-1200, exploring 3.3–3.6 and occasional load tweaks (including 130–150g experiments). One NCT Filter D detour existed; the settled path returned to F-NAT.

Settled at 3.4

R-089 / R-100 / R-102 at 3.4 / 120g are confirmation roasts. When a home-roast log goes quiet on notes after a clear “want more chocolate” problem statement, that usually means the problem is solved — not that the data stopped mattering.

Keep recipe

SettingValue
ProfileF-NAT 0-1200
Level3.4
Batch120g
Typical DTR band~19–22% on successful mid-band runs
Goal in the cupChocolate, nut brittle, low acidity, medium body

Full metrics chart and timeline: Decaf Brazil case study →

What not to do

  1. Don’t stay forever at a “fine but not chocolate enough” level out of fear of darkness.
  2. Don’t interpret missing late comments as missing success — confirmation roasts are valid.
  3. Don’t apply light washed-filter packs if the goal is malted chocolate and body.
  4. Don’t forget: higher Kaffelogic level = darker roast.

Related reading

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How to roast Swiss Water decaf Brazil on a Kaffelogic Nano

Keep recipe from a 12-roast log for natural-process Decaf Brazil DEC02

1

Load 120g green

F-Series style load for stable development.

2

Select F-NAT 0-1200 at level 3.4

Medium-dark on the Kaffelogic scale for chocolate and nut brittle without ash.

3

Develop through first crack for sweetness

Goal is malted chocolate and nut notes — not light tea-like acidity.

4

Rest and brew for chocolate

Judge for chocolate milk, nut brittle, low acidity, medium body.

5

Repeat, don’t chase

Once the cup is consistently good, log confirmations rather than reinventing the profile every batch.

Frequently Asked Questions

What is the best Kaffelogic profile for Swiss Water decaf Brazil?
In this log, F-NAT 0-1200 at level 3.4 with a 120g batch became the keep recipe for a chocolate-nutty goal. Early level 3.0 was only decent and still wanted more chocolate and less acidity.
Should decaf be roasted differently from caffeinated Brazil?
Decaf often behaves denser and can need careful development into chocolate/sweet notes without ash. This log stayed in the natural-process F-NAT family and raised level into the mid-3s rather than chasing light filter packs.
What roast level for chocolate-nutty decaf Brazil?
On the Kaffelogic scale (higher = darker), 3.3–3.6 was the productive band; 3.4 / 120g is the settled repeat. Remember higher numbers mean darker roasts.
Why are there few tasting notes late in the log?
Once the cup was consistently good, later batches were light tweaks and confirmations — not failures. The absence of complaints is the signal that 3.4 stuck.
What DTR works for this decaf?
Successful mid-band roasts often landed near 19–22% DTR with ~14% roast loss. Very high DTR spikes were less useful as a goal than repeating the 3.4 recipe that tasted right.
Roasting

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