Same farm. Same altitude. Same roaster. The only variable separating this from the Mae Chedi Anaerobic Natural is what happens to the cherry in the first 24 to 48 hours after harvest.
Washed processing removes that variable deliberately. Cherry skin comes off on the day of harvest, fermentation happens in water tanks, and then the parchment-covered beans are washed clean before drying. Every fruit-layer compound — the volatile esters, the lactic acid byproducts, the fermentation-derived aromatics — gets stripped away before the bean ever dries. What reaches your grinder is the Chiang Mai variety and the Mae Chedi terroir, unmediated by processing influence.
Chiang Mai is a regional variety adapted to northern Thailand's growing conditions. At 1,250 meters in Chiang Rai, the altitude sits below the 1,400–1,900m sweet spot where the synthesis data shows the most concentrated soluble development. Cherry maturation at this elevation is somewhat faster than at higher altitude, meaning the seed accumulates organic acids and sugars over a shorter development window. Washed processing, which yields slightly higher extraction percentages than naturals, helps maximize what's there.
Medium-dark roasting carries this to a different chemical place than it would be at light or medium. Chlorogenic acids — the main driver of brightness in lightly roasted washed coffees — partially degrade by this roast level, converting toward quinic acid. The flavor energy shifts from citric acid-driven brightness into Maillard territory: nutty, chocolatey compounds from the browning of amino acids and reducing sugars. Strecker degradation of valine and leucine specifically contributes methylpropanal and 3-methylbutanal, the characteristic malt-and-chocolate compounds that define medium-dark washed coffees.
The cup will be defined by roast chemistry more than origin brightness — which is exactly what [washed processing](/blog/coffee-processing-methods-explained) at this roast level is built to produce.
Cold Brew is the top-ranked method at 87/100 for this medium-dark Mae Chedi Washed, and the chemistry explains why. Cold water (1°C) is kinetically unable to efficiently extract the bitter compounds compounds that dominate poorly brewed medium-dark coffee — those slow-extracting carbon and tobacco notes require heat-activated diffusion to dissolve. What cold water does extract efficiently are the Maillard-derived chocolate and malt compounds that this roast level develops, particularly over the 12-18 hour steep window. The grind at 930μm (30μm coarser than default) prevents over-extraction during that long contact time. The 1:6.8-7.8 concentrate ratio pulls maximum soluble material from the bean while keeping the bitter fraction suppressed by temperature. The result is the smoothest, most body-forward expression of this bean's roast character.
Troubleshooting
bitter: Grind coarser by ~22μm and drop temperature 1°C. If using warmer ambient water or a slightly elevated steep temperature, the extraction of dry distillate compounds increases. Cold brew suppresses bitterness by temperature, so any warmth undermines that mechanism — check your steep environment.
strong: Reduce dose by 1g or increase water by 15g. Cold brew concentrate is designed for dilution — the 1:6.8-7.8 ratio produces a concentrate, not a ready-to-drink brew. If drinking undiluted, the medium-dark roast's high solubility makes this ratio quite strong. Add water 1:1 before adjusting the recipe.
flat: Grind finer by ~22μm and increase temperature 2°C; check bean freshness and water mineral content. Flat cold brew from a medium-dark bean usually means stale beans — medium-dark roast loses CO2 and volatile aromatics faster than light roast. If freshness is confirmed, very soft water lacks minerals for proper extraction.
At 85/100, espresso is a strong match for this medium-dark Chiang Mai washed. The high solubility from the dark roast means extraction under pressure is efficient — the recipe's tighter ratio of 1:1.3-2.3 exploits that solubility to produce a concentrated, chocolate-forward shot without needing to push extraction time. Temperature drops to 90°C, 3°C below default, specifically because medium-dark roast's bitter compounds compounds (the slow-extracting bitter carbons and tobacco notes) extract aggressively under espresso's 9-bar pressure; cooler water provides a margin of control. The grind sits 30μm coarser than default to balance that pressure-driven extraction. The ristretto end of this ratio — 1:1.3 — is viable because the high solubility means enough chocolate and malt compounds extract quickly before the bitter tail arrives.
Troubleshooting
bitter: Grind coarser by ~10μm and drop temperature 1°C. Pressure extraction amplifies the dry distillate content of medium-dark roast — these bitter carbons extract readily at 9 bar. A small grind adjustment has a larger extraction impact under pressure than in pour-over methods.
strong: Reduce dose by 1g or increase yield by 15g water out. Medium-dark roast's high solubility means espresso TDS builds quickly. The narrow ratio window makes strength sensitive — a 1g dose change shifts beverage weight by 3-4g. Adjust yield before touching the dose.
The AeroPress at 84/100 handles this medium-dark Mae Chedi well because the short steep time and low temperature work together to limit over-extraction. At 82°C — 3°C below default, suited to the medium-dark roast level — the extraction rate for bitter compounds slows while the faster-extracting Maillard compounds (malt, chocolate, caramel) still have enough time in the 1:00-2:00 window to dissolve. The 30μm coarser grind further reduces extraction speed. The AeroPress's ability to use pressure for the final push means you're not dependent on gravity pulling every last compound out of the bed — you control the stop point. For this medium-dark bean, which has CGA partially degraded toward bitter compounds from roast development, keeping temperature low and contact time short prevents that bitter compounds from roast development from dominating the cup.
Troubleshooting
bitter: Grind coarser by ~22μm and drop temperature 1°C. At medium-dark roast, quinic acid from CGA degradation and dry distillate compounds are close to the extraction threshold. The AeroPress's pressure finish can push extraction further than expected — a coarser grind is the primary control.
strong: Reduce dose by 1g or increase water by 15g. The 1:12.8-13.8 ratio is already tighter than pour-over methods. Medium-dark roast has high solubility, so a small dose increase has an outsized effect on TDS. Start with water adjustment before touching the dose.
The Clever Dripper at 83/100 gives this Mae Chedi Washed something the V60 can't: a controlled steep before the drain valve opens. That immersion phase allows the medium-dark roast's Maillard compounds — the nutty, malt, and chocolate notes that are the primary flavor energy of this bean at this roast level — to extract evenly at 91°C before the paper filter does any work. The 3°C temperature reduction from default addresses the medium-dark roast's elevated bitter compounds content. The 30μm coarser grind works with the immersion phase rather than against it. Unlike the V60 or Chemex, the Clever's hybrid design means water contact time is predictable and consistent regardless of pour technique, which matters when you're navigating a medium-dark bean whose flavor balance is roast-driven rather than origin-driven.
Troubleshooting
bitter: Grind coarser by ~22μm and drop temperature 1°C. The Clever's immersion phase is forgiving, but medium-dark roast's dry distillate compounds can still accumulate during the steep. If the grind is too fine, the concentration of bitter carbons builds before the drain valve opens.
strong: Reduce dose by 1g or increase water by 15g. The Clever's immersion method extracts very efficiently — all grounds stay in contact with water for the full steep. Medium-dark roast has high solubility, so the combination produces high TDS. Adjust water first.
The Moka Pot at 82/100 works with this medium-dark Mae Chedi because its ~1.5-bar pressure accelerates extraction of the Maillard compounds — malt, chocolate, caramel — without the full intensity of espresso's 9 bar. Temperature at 97°C reflects the pre-boiled water method, which is appropriate for this bean's medium-dark roast: the moka pot's heat buildup during brewing means starting with boiling water shortens the time grounds spend in contact with rising steam, reducing the bitter extraction window. The 30μm coarser grind is essential here — at moka pot's pressure and temperature, a fine grind over-extracts the bitter compounds compounds that accumulate at this roast level. The 1:9.8-10.8 ratio concentrates the chocolate and malt character into a small, intense serve suited to adding milk or drinking straight.
Troubleshooting
bitter: Grind coarser by ~22μm and drop temperature by starting with cooler pre-boiled water. The moka pot's heat buildup can push extraction of medium-dark roast's dry distillate compounds aggressively. Coarser grind is the primary lever — the pot's design limits temperature control otherwise.
strong: Reduce dose by 1g or increase water by 15g in the base chamber. The moka pot concentrates extraction by design — medium-dark roast's high solubility compounds this. At the 1:9.8-10.8 ratio, even small dose changes have outsized strength effects.
French Press at 82/100 earns a solid match because its metal filter passes the oils that carry this medium-dark bean's body and mouthfeel. Maillard-produced melanoidins — the high-molecular-weight browning products that give body and texture — pass through unimpeded. The coarse 1030μm grind (30μm over default) reduces surface area exposure during the long 4-8 minute steep, preventing over-extraction of the bitter compounds compounds that are abundant at this roast level. Temperature drops to 93°C from a default that would otherwise pull too many bitter compounds from the medium-dark Mae Chedi. The extended steep window is forgiving here: the Chiang Mai variety's moderate density means it extracts steadily rather than in a rush, and the coarse grind provides a buffer against the longer end of the brew window.
Troubleshooting
bitter: Grind coarser by ~22μm and drop temperature 1°C. French Press's long steep and metal filter mean every compound has access to the cup. Medium-dark roast has significant dry distillate content — if the grind is too fine, those slow-extracting bitter carbons will accumulate over the 4-8 minute window.
strong: Reduce dose by 1g or increase water by 15g. French Press uses no paper filter, so all oils and fine particles contribute to TDS. Medium-dark roast has high solubility. The 1:14.8-15.8 ratio is on the stronger side — a small water increase resolves this without affecting flavor character.
The Kalita Wave's flat-bottom design distributes water more evenly across the bed than a conical dripper, which matters for this medium-dark Mae Chedi at 80/100. The even saturation means the Maillard-derived malt and chocolate compounds — which extract in the middle phase of the extraction sequence — get consistent contact time across the whole puck rather than the faster center flow of a V60. Temperature is set to 91°C, 3°C below default, to avoid pulling too many bitter bitter compounds from the darkened roast. The 30μm coarser grind (roast +20μm, Chiang Mai variety +10μm) slows the extraction rate slightly. The Kalita's balanced sweetness character makes it a better fit than the V60 or Chemex for a medium-dark bean that has shifted its flavor energy toward caramel and nuts.
Troubleshooting
bitter: Grind coarser by ~22μm and drop temperature 1°C. Medium-dark roast pushes the flavor energy toward dry distillate compounds at extraction's tail end. The Kalita's flat bottom helps even extraction, but over-extraction still accumulates bitter carbons — go coarser before dropping temperature.
thin: Increase dose by 1g or reduce water by 15g; try a metal filter for more body. At 1,250m, this bean has lower soluble density than high-altitude origins. The paper filter removes oils that carry body. A metal filter passes those oils into the cup at the cost of some sediment.
The 69/100 match score tells the story before you pour a drop: V60 is optimized for clarity and brightness, and this Mae Chedi Washed at medium-dark is built for the opposite. The 3°C temperature drop to 91°C reduces extraction of the bitter compounds that accumulate at medium-dark roast levels — those slow-extracting carbon and tobacco compounds that dominate if temperature stays high. The grind sits 30μm coarser than default, primarily for the medium-dark roast's higher solubility, with the variety characteristics of this Chiang Mai lot pushing slightly coarser as well. At this roast level, the Maillard-derived malt and chocolate compounds are what you want in the cup; V60's faster flow and conical geometry push water through too quickly to build the body those compounds need. A Clever Dripper or French Press extracts these flavors more forgivingly.
Troubleshooting
bitter: Grind coarser by ~22μm and drop temperature 1°C. Medium-dark roast has elevated dry distillate compounds — slow-extracting bitter carbons — that a fast-draining V60 can over-extract if the grind is too fine. These are the last compounds to extract and the least forgiving.
thin: Increase dose by 1g or reduce water by 15g; alternatively try a metal filter to allow oils through. The V60's paper filter strips the oils that carry body in this Maillard-forward medium-dark roast. At 1,250m, the bean has lower soluble density than high-altitude origins, so the filter compounds the thinness.
At 65/100, the Chemex is the weakest match for this bean, and the filter is why. Chemex's 20-30% thicker paper strips not just fines but the oils that carry the malt and chocolate character of this medium-dark Chiang Mai washed. The 3°C temperature reduction to 91°C is correct — it limits extraction of the bitter compounds compounds that build at this roast level — but the filter's filtration effect works against the cup you want. The grind is set 30μm coarser to compensate for elevated solubility from the dark roast. What remains after the Chemex filter does its work will be cleaner than this bean's profile calls for. If you're using a Chemex, accept a lighter-bodied, brighter result, or boost the dose by 2-3g to compensate for what the filter removes.
Troubleshooting
thin: Increase dose by 1g or reduce water by 15g; consider a metal filter if body is the priority. Chemex's thick paper strips the oils that are the primary body carriers in this medium-dark washed. This is structural — the filter design fundamentally conflicts with what this roast level produces.
bitter: Grind coarser by ~22μm and reduce temperature 1°C. The Chemex's slower flow can build extraction time unexpectedly, allowing bitter dry distillates from the medium-dark roast to over-extract. The 30μm coarser grind from the recipe is a starting point — go further if bitterness persists.