Methodical Coffee

Colombia, Ventola Natural

colombia medium roast anaerobic_natural castillo

cherrycolajasmine

Felipe Trujillo's fermentation protocol is a two-stage process. First, 12 hours of aerobic fermentation — the cherries exposed to oxygen, acetic acid bacteria active, the pH dropping. Then the batch moves into hermetic tanks for a full week of anaerobic fermentation where the microbial population flips. Without oxygen, lactic acid bacteria take over. Volatile ester production climbs. The cherries spend another five to six weeks on raised beds after that, drying slowly in Antioquia's mountain air. The cherry and cola notes come from different chemical families converging. Cherry traces to malic acid and fruit-derived esters generated during the anaerobic stage — compounds that natural processing concentrates through prolonged seed-to-fruit contact. Cola is more interesting. It points to phosphoric acid, which produces a sparkling, almost sweet-sour brightness distinct from the sharper citric acid character found in most specialty coffee. Phosphoric acid's sensation is effervescent rather than cutting. Jasmine sits in the volatile fraction. Phenylalanine — an amino acid that accumulates in dense, high-altitude seeds — breaks down during roasting through Strecker degradation into phenylacetaldehyde. This compound is responsible for honey-floral aromatics. At 1950 meters, the precursor concentration is high enough for the floral note to persist even through medium roast development, where many delicate volatiles degrade. Medium roasting builds body here through melanoidin formation — heavy polymers that add viscosity and a perception of weight. Castillo, a rust-resistant Colombian hybrid, produces a sturdy bean that handles medium development without losing its acid structure entirely. The Maillard reaction generates the brown, caramelized aromatics that bridge the gap between the fruity top notes and the heavier chocolate-adjacent base. Sweetness reads as intense because of furanones and maltol — roasting byproducts that smell sweet despite containing no sugar.

Chemex 6-Cup 89/100

Grind: 560μm Temp: 90°C Ratio: 1:15.5-1:16.5 Time: 3:30-4:30

The Chemex's 20-30% thicker paper filter is particularly well-matched to this anaerobic natural Castillo from 1950m. Anaerobic fermentation on natural-process Colombian builds volatile aromatic compounds and fruit-derived aromatics that paper filtration can actually clarify rather than strip — the oils and heavier compounds that would muddy those cherry and jasmine notes are caught by the filter matrix, letting the cola-like phosphoric brightness and floral delicacy come through cleanly. Temperature is dialed down 4°C from default (roast contributing -2°C, anaerobic processing contributing -2.5°C) because medium-roasted Castillo at this altitude has already built sufficient soluble development — aggressive heat risks over-extracting the fermentation volatiles before the caramel and cherry character fully resolves. The slightly coarser grind (+10μm for anaerobic processing) compensates flow rate through the slower Chemex filter.

Troubleshooting

sour: Grind finer by ~22μm and raise temp by 1°C. Anaerobic fermentation builds acids early in extraction; sourness here means you're stopping in the fruity acid phase before cherry and cola sweetness emerge. Finer grind increases surface area to push extraction past that threshold.

thin: Add 1g dose or reduce water by 15g. At 1950m this Castillo has medium density and solubility — thin cups indicate TDS is simply too low. A metal filter would also pass more oils and body-building melanoidins if thinness persists.

Hario V60-02 88/100

Grind: 510μm Temp: 90°C Ratio: 1:15.5-1:16.5 Time: 2:30-3:30

The V60's fast-draining conical design is well-suited to the medium solubility of this anaerobic natural Castillo, but the paper filter does critical work here: anaerobic fermentation on natural-process coffee produces intensely aromatic compounds that express most cleanly when the oils are removed from the cup. The filter traps those oils and delivers the aromatics in cleaner solution — which is why the cherry and jasmine notes read as distinct rather than blended into heavy body. Temperature sits at 90°C (4°C below default) to protect these fragile fermentation-derived aromatics from thermal degradation — the lower temperature reflects both the medium roast's higher solubility and the heat-sensitivity of compounds created during anaerobic processing. The slightly coarser grind (10μm above default) accounts for the natural processing and prevents over-restriction in a conical dripper where flow is already variable.

Troubleshooting

sour: Grind finer by ~22μm and raise temp by 1°C. In V60's conical geometry, coarser grinds can create uneven bed density, leaving some particles underextracted. The cherry and cola notes from this anaerobic process only emerge past the initial acid extraction phase — tighten the grind.

flat: Grind finer by ~22μm and raise temp by 2°C, then check water mineral content. Anaerobic volatile compounds require adequate mineral content for full expression — very soft water (below 50 ppm) can suppress extraction and leave the fermentation character muted despite correct brew parameters.

Kalita Wave 185 87/100

Grind: 540μm Temp: 90°C Ratio: 1:16.5-1:17.5 Time: 3:00-4:00

The Kalita Wave's flat-bottom geometry and three-hole drain create more uniform water distribution through the bed than conical drippers — for this anaerobic natural Castillo at 1950m, that evenness matters. Uneven extraction produces cups that taste simultaneously sour and bitter even at correct average yield, which would mask the cherry and jasmine clarity this bean is built for. The flat bed means fewer under-extracted particles near the walls, which is relevant for Castillo: its medium yield/medium density profile benefits from consistent contact time across the bed. Temperature is 90°C (-4°C from default), and grind is 540μm (+10μm for anaerobic processing), placing this slightly coarser than the V60 spec to account for the three-hole flow restriction. Paper filter still strips the anaerobic-process oils for clarity.

Troubleshooting

sour: Grind finer by ~22μm and raise temp by 1°C. In a flat-bottom bed, sourness usually indicates uniform under-extraction — you're extracting acids but not reaching the caramel and cherry sweetness. Finer grind or higher temp pushes the entire bed past the acid phase.

flat: Grind finer by ~22μm and raise temp by 2°C; verify water quality. Flatness in a Kalita often traces to stale beans or mineral-deficient water. This anaerobic natural's cola and jasmine character depends on both fresh volatile compounds and adequate extraction driving them into solution.

AeroPress 87/100

Grind: 410μm Temp: 81°C Ratio: 1:12.5-1:13.5 Time: 1:00-2:00

AeroPress uses a paper filter and pressure assist, which together handle anaerobic natural processing unusually well: the paper removes the oil fraction that carries the heavier fermentation compounds, while light pressure shortens contact time enough to avoid over-extracting at 81°C. That low temperature — 4°C below AeroPress default from roast and processing adjustments — is intentional. AeroPress's immersion-plus-pressure extraction is efficient enough at 81°C to reach the ethyl ester compounds responsible for cherry and jasmine, while the reduced heat protects those fragile fermentation volatiles during the 1-2 minute steep. The ratio sits at 1:12.5-13.5, producing a slightly concentrated brew at 182g — dilute with 30-50g hot water if you prefer filter-coffee strength.

Troubleshooting

strong: Reduce dose by 1g or add 15g water. At 1:12.5 the AeroPress recipe is already concentrated — small variations in dose or grind coarseness have outsized TDS impact. This Colombian anaerobic natural has medium solubility, so strength accumulates quickly in immersion.

bitter: Grind coarser by ~22μm and drop temp by 1°C. At 81°C bitterness in AeroPress almost always means over-extraction from too-fine grind: the pressure-assisted extraction is efficient, and Castillo's medium density means it responds quickly to grind changes. Coarser grind gives you more control.

Clever Dripper 87/100

Grind: 540μm Temp: 90°C Ratio: 1:15.5-1:16.5 Time: 3:00-4:00

The Clever Dripper combines immersion steeping with paper-filter clarity — for an anaerobic natural Colombian this is a meaningful hybrid. The immersion phase (3-4 minutes at 90°C) gives the medium-solubility Castillo consistent, even contact time without relying on pour technique to distribute water evenly. Immersion also benefits anaerobic-process volatiles: compounds extracted early in the steep stay in contact with the grounds as the concentration gradient builds, which means the cherry and cola character has time to fully develop before the drain opens. The paper filter then removes the natural-process oils on exit. This is why the Clever Dripper scores 87/100 here despite being a simpler method — consistent immersion compensates for the extraction challenge that comes with a 4°C cooler brew temp.

Troubleshooting

strong: Reduce dose by 1g or add 15g water. Clever Dripper's closed-bottom immersion concentrates extraction faster than open-drain pour-overs — this Colombian anaerobic natural at medium solubility can tip into over-strength with minor dose creep. Adjust ratio first before changing grind.

bitter: Grind coarser by ~22μm and reduce temp by 1°C. In immersion, steep time and grind together control yield — if the drain is slow and steep runs long, the coarser grind slows extraction enough to prevent bitter dry distillates from dominating the cherry and jasmine notes.

Espresso 74/100

Grind: 260μm Temp: 89°C Ratio: 1:1.5-1:2.5 Time: 0:25-0:30

Espresso at 74/100 for this bean reflects a real compatibility tension: anaerobic natural processing builds volatile aromatic compounds that espresso's 9-bar pressure and 25-35 second contact time can overextract, pushing the cherry and cola forward to sharp intensity while the delicate jasmine can get lost. The recipe compensates: temperature is 89°C (-4°C from default) and grind is at 260μm (+10μm for anaerobic processing, coarser than a standard medium-roast Castillo espresso). That coarser spec slows extraction slightly, preserving the aromatic mid-extraction zone where fermentation volatiles resolve without continuing into the bitter compounds phase. Expect this as a fruit-forward, acidic espresso — the cola note and cherry will be intense and concentrated. A 1:1.5-2.5 ratio gives you flexibility to pull long if the shot tastes sharp.

Troubleshooting

sour: Grind finer by ~10μm and raise temp by 1°C. Espresso extracts in a narrow window — sourness here means the shot stopped extracting before the Castillo's cherry sweetness resolved. Anaerobic processing accentuates early-extraction acids; small grind adjustments have large yield impact.

strong: Reduce dose by 1g or let the shot run to the higher end of the 1:2.5 ratio. This Colombian anaerobic natural at medium roast has adequate solubility to over-concentrate in espresso quickly. Pull slightly longer before adjusting dose.

Moka Pot 65/100

Grind: 360μm Temp: 96°C Ratio: 1:9.5-1:10.5 Time: 4:00-5:00

The Moka Pot's 65/100 score reflects the fundamental mismatch between its extraction mechanism and this bean's character: the metal mesh passes all the natural-process and anaerobic-fermentation oils, which compete with the delicate jasmine and cherry notes rather than complementing them. Cola and cherry in a Moka Pot context become bold and jammy rather than nuanced. That said, the recipe is calibrated for the best possible outcome: 96°C (roast and processing adjustments net -4°C from the moka pot's 100°C default), 360μm grind (+10μm for anaerobic processing, preventing the over-fine grind that causes bitter sputtering), and 1:10 ratio. Pre-boiling the water and using low-medium heat prevents steam from cooking the grounds before extraction begins — this is especially important here because anaerobic volatile compounds are the most heat-sensitive fraction.

Troubleshooting

strong: Reduce dose by 1g or add 15g water. Moka Pot's fixed chamber volume makes dose management critical — this Colombian anaerobic natural's medium solubility concentrates quickly at the high brew temperatures and partial pressure the Moka Pot generates.

sour: Grind finer by ~22μm and raise temp by 1°C. Moka Pot sourness typically means incomplete extraction before the sputtering phase — the cherry and cola sweetness is in the second half of the extraction window. Finer grind ensures more solubles reach the cup before pressure drops.

French Press 63/100

Grind: 1010μm Temp: 92°C Ratio: 1:14.5-1:15.5 Time: 4:00-8:00

French Press scores 63/100 for this bean primarily because the metal mesh passes all the anaerobic natural oils, which in a 4-8 minute immersion have plenty of time to extract into the cup and can overwhelm the cherry and jasmine delicacy with heavier body and earthy fermentation texture. The recipe compensates with temperature at 92°C — 4°C below the French Press's 96°C default, reflecting both the roast and processing adjustments — coarse 1010μm grind (+10μm for anaerobic), and a longer potential steep window (4-8 minutes). The Hoffmann method applies here: steep 4 minutes, then wait 5-8 additional minutes after pressing — the extra rest allows grounds to settle, producing a cleaner cup from a metal-filtered brew. That settling time matters for anaerobic-process coffee specifically: fines carry the heaviest fermentation compounds and sink away from the cup.

Troubleshooting

strong: Reduce dose by 1g or add 15g water. French Press immersion with anaerobic natural oils extracts intensely — this Colombian Castillo at medium roast produces significant dissolved solids over a full steep, and the unfiltered oils add perceived body on top of TDS.

bitter: Grind coarser by ~22μm and reduce temp by 1°C, or shorten steep to the 4-minute end of the range. In immersion, bitter dry distillates accumulate the longer extraction continues — the cherry character peaks earlier in the steep than the bitterness onset.

Cold Brew 61/100

Grind: 910μm Temp: 0°C Ratio: 1:6.5-1:7.5 Time: 720:00-1080:00

Cold Brew scores 61/100 for this medium-roast anaerobic natural, which is surprisingly workable relative to light roasts. Medium roast has degraded the hardest-to-extract CGAs and built caramelization products that dissolve more readily at cold temperatures than the dense, extraction-resistant structure of light roasting in light roasts. The cherry, cola, and jasmine notes do compress into a flatter profile at cold temperatures — the fruity acids that animate the cup at hot brew temperatures partly disappear (cold water extracts 28-50% fewer titratable acids). But the cola character, which is phosphoric-acid adjacent, survives better than citric-forward notes. Recipe is 80g/560g at 910μm (+10μm for anaerobic processing) for 12-18 hours. The flat troubleshooting score of 40 flags the highest risk: under-extracted, flat cold brew is easy to produce if steep time runs short or grind is too coarse.

Troubleshooting

flat: Grind finer by ~22μm or extend steep by 2-4 hours. Cold brew of anaerobic natural Colombian loses fruit volatiles to cold-temperature suppression — flatness means you've also under-extracted the caramel and cola character. Check water mineral content; very soft water exacerbates under-extraction.

strong: Reduce dose by 1g or add 15g water to the concentrate, or dilute more aggressively before serving. At 1:7 this recipe is already a concentrate — the anaerobic processing adds flavor density on top of the concentrate TDS.