SL28 was bred at Kenya's Scott Laboratories in the 1930s from a Bourbon-lineage selection, and it spent most of its history as East Africa's benchmark for cup quality — blackcurrant, citrus, intense sweetness, intense acidity. Planting it in Costa Rica is an experiment in what happens when you take a variety shaped by Kenyan terroir and run it through Central American conditions.
The result here is stacked deviations in the same direction. At 1,960 meters, this is among the highest-grown Costa Rican coffees in the specialty market — well above the typical 1,501–1,707m range and approaching the upper ceiling of the quality sweet spot for equatorial latitudes. Higher altitude means slower cherry maturation: research shows development extends from 6–8 months to 9–11 months at altitude, with the diurnal temperature swings preserving photosynthesized sugars overnight rather than burning them off through respiration. More concentrated solubles mean more extraction potential and more to work with in the cup.
Washed processing removes the fruit mucilage completely, keeping the focus on SL28's variety-driven character rather than fermentation-added compounds. That toffee note is Maillard territory — caramelization products and melanoidins forming as sugars and amino acids brown during roasting. The cranberry comes from citric acid, which is the only organic acid in coffee that consistently exceeds its sensory detection threshold; at light roast the chlorogenic acid levels stay high, sharpening that brightness. The citrus note reinforces the citric-acid axis.
SL28 carries large beans and low yield — it was selected for quality, not productivity. That [variety choice](/blog/how-to-read-coffee-bag-label) signals a specific intent: maximize cup character at the cost of output, at an elevation that already demands more from both plant and farmer.
Chemex earns the top match score for this SL28 because the thick bonded paper filter is the ideal instrument for a variety built around citric brightness. SL28's blackcurrant-and-citrus character is carried by water-soluble acids and volatile aromatics—exactly the fraction paper maximizes by blocking oils and fine particles that would add turbidity. The grind lands at 510μm, 40μm finer than Chemex default—the light roast adjustment applies here, though SL28 doesn't carry the additional delicate-aromatic designation that Gesha does. Temperature holds at 94°C rather than the 93°C dialed in for the Gesha lot; SL28 roasts like Bourbon and can handle a degree more heat to push extraction through its high-density, 1,960m-grown beans. The 1:15–1:16 ratio concentrates the toffee and cranberry compounds at perceptible levels while leaving room for the citrus acidity to remain bright rather than sour.
Troubleshooting
sour: Grind finer by ~22μm and raise temp 1°C to 95°C. SL28's cranberry note is citric-acid-dominant; sourness means extraction stalled before reaching the toffee-range Maillard compounds. At 1,960m, this bean has very high density—extra surface area from finer grind is the primary lever to push past the acid-only phase.
thin: Add 1g dose (to 29g) or reduce water by 15g. SL28 at light roast has low solubility, and Chemex's thick paper amplifies this by stripping all oils. A metal Chemex filter alternative passes lipids and heavier melanoidins, adding tactile body beneath the cranberry and toffee without sacrificing clarity.
The V60 at 88/100 for this SL28 is a strong match because V60's balanced flow rate and thinner filter preserve more texture than Chemex while still highlighting the variety's acid-driven character. SL28 was selected by Scott Laboratories for outstanding cup quality at the expense of yield—its large beans contain concentrated solubles accumulated through slow maturation at altitude. The 460μm grind, 40μm finer than V60 default, is the minimum adjustment needed to overcome light roast's reduced solubility; SL28 doesn't require the additional 10μm Gesha variety downward push. At 94°C and 1:15–1:16, the V60 allows the citrus and toffee to emerge sequentially: bright acidity arrives first during the faster extraction phase, with toffee-range caramelization compounds building through the drawdown. Pour technique matters here—pouring on the filter walls risks collapse and channeling, which would produce uneven extraction from these large, dense beans.
Troubleshooting
sour: Grind finer by ~22μm and raise temp 1°C to 95°C. V60's open drain hole means flow can outpace extraction on these dense SL28 beans from 1,960m. Sour output means fast phase dominated; finer grind slows drawdown and increases surface area simultaneously, letting toffee and cranberry sweet notes catch up.
thin: Add 1g dose or reduce water by 15g. Light-roast SL28 at 1:15 already runs leaner than a medium roast at the same ratio. If toffee reads as ghostly rather than present, a metal V60 filter recovers the oils that V60 paper strips—adding perceptible body and softening the citrus edge into something richer.
The Kalita Wave ties V60 at 88/100 for this SL28, offering a different mechanism to achieve similar results. The flat-bottom three-hole design produces a more controlled, even flow rate than the V60's single drain—this matters for SL28's large beans, which have a less uniform surface area per gram than smaller-bean varieties. Even water distribution prevents the partial channeling that would leave some large beans underextracted while others are at target yield. The 490μm grind is slightly coarser than V60 (460μm) because Kalita's consistent flat-bed contact compensates somewhat for less total surface area—the even saturation achieves similar extraction evenness with a coarser particle. Temperature and ratio are identical to V60 at 94°C and 1:15–1:16. The Kalita is notably more forgiving of imperfect technique, which makes it the stronger recommendation for home brewers who want SL28's cranberry-toffee character without precise pour control.
Troubleshooting
sour: Grind finer by ~22μm and raise temp 1°C to 95°C. The Kalita's flat bed provides even saturation, but SL28's large beans at 1,960m still need sufficient surface area to extract sweetness compounds. Sourness means the even contact helped but the particle size was too coarse to hit target yield on this high-density bean.
thin: Add 1g dose or reduce water by 15g. Avoid pouring directly on the paper walls—the Kalita filter can collapse and restrict flow, artificially thinning the cup through underextraction rather than dilution. If dose adjustment doesn't help, a metal Kalita filter adds body by allowing oils and melanoidins through.
AeroPress scores 82/100 for this SL28. The sealed immersion chamber gives this dense, low-solubility light roast something that continuous-pour methods cannot: a constant, high-concentration gradient throughout extraction, which helps coax solubles from the tightly packed cell structure. The 360μm grind — 40μm finer than default — increases surface area to compensate for the short 1–2 minute brew window, ensuring adequate extraction from a bean that resists giving up its flavors easily. The sealed chamber also maintains consistent slurry temperature throughout the steep, so heat stays in contact with the grounds for the full duration. Pressing with consistent pressure at the end produces a small amount of espresso-like crema, concentrating the cranberry and toffee notes into a more intense, shorter cup.
Troubleshooting
sour: Grind finer by ~22μm and raise temp 1°C to 86°C. AeroPress's short contact window makes grind size the dominant extraction variable. This SL28 from 1,960m has high density; even with immersion mechanics, insufficient surface area on these large beans keeps extraction in the acid-dominant fast phase.
thin: Add 1g dose or reduce water by 15g toward a 1:11 ratio. AeroPress paper filter removes oils that contribute body; light-roast SL28's low solubility compounds this. Switching to a metal AeroPress disk passes lipids that recover the mouthfeel and let the toffee character develop a more persistent mid-palate presence.
The Clever Dripper's hybrid immersion-then-drain mechanism scores 82/100 for this SL28—tied with AeroPress but operating on a different extraction logic. Immersion lets water saturate all particles equally before drainage begins, addressing the evenness-of-extraction problem that SL28's large, dense beans create in continuous-pour methods. Some large-bean varieties extract unevenly in V60 because water flows preferentially through already-wet particles; Clever's sealed soak phase prevents this. The 490μm grind is identical to Kalita's, and temperature holds at 94°C matching the V60 and Chemex. Paper filter ensures the citrus and cranberry come through clearly without oil interference. The 1:15–1:16 ratio is on the leaner end for immersion methods, compensating for the longer contact time that would otherwise push TDS higher than intended.
Troubleshooting
sour: Grind finer by ~22μm and raise temp 1°C to 95°C. The Clever Dripper's immersion phase mitigates but doesn't eliminate underextraction risk on this dense, 1,960m SL28. Sourness means the soak time provided even contact but insufficient extraction yield—finer grind shortens diffusion distance in the large SL28 beans.
thin: Add 1g dose or reduce water by 15g. If the cup is clean but hollow, extend the immersion time by 30–60 seconds before triggering drainage. The Clever's paper filter removes body-contributing oils; a metal filter alternative allows melanoidins and lipids through, which noticeably fills out the toffee mid-palate on this SL28.
SL28 espresso at 81/100 is a compelling but demanding option. SL28 roasts like Bourbon — it's in the same genetic Bourbon-related group and follows similar roasting parameters — but its cup character is far more acid-intense, which means espresso amplifies the cranberry and citrus to levels that can tip into sourness if not dialed precisely. Light-roast espresso demands a longer ratio (1:1.9–2.9), preinfusion to wet the dense puck before full 9-bar pressure, and grind 40μm finer than espresso default to overcome the light roast's reduced solubility. Temperature runs at 93°C — the standard espresso default — which balances extraction efficiency against the risk of sour over-accentuation under pressure. Expect shots that taste like concentrated cranberry and toffee rather than the chocolate-dominant profile many espresso drinkers default to.
Troubleshooting
sour: Grind finer by ~10μm and raise temp 1°C to 94°C. SL28 espresso under-extracts easily due to high bean density at 1,960m and light roast's reduced solubility. Sourness is the dominant failure mode; finer grind increases hydraulic resistance slightly but raises extraction yield enough to pull the toffee compounds into the shot.
thin: Add 1g dose (to 20g) or pull a tighter ratio toward 1:1.9. Light SL28 espresso runs lean on dissolved solids; the cranberry and citrus notes can register as sharp but thin. A shorter, more concentrated pull sacrifices shot volume but dramatically raises TDS and makes the toffee sweetness more present in the finish.
Moka Pot scores 79/100 for this SL28—a strong showing for an unfiltered method. Moka's 1–1.5 bar pressure concentrates the citrus and cranberry notes of this light-roast SL28 into a more intense format than filter methods, and the unfiltered basket means coffee oils remain in the cup, adding a textural dimension that complements the variety's high-acidity profile. SL28's large beans work against it slightly here: the medium-fine 310μm grind needs to be consistently dialed in, since coarser particles in the basket create uneven flow channels and channeling produces sour streaks through an otherwise well-extracted cup. Temperature runs at 100°C (fully pre-boiled water in the chamber), which is higher than pour-over recommendations but necessary for Moka Pot mechanics—the heat differential drives water upward through the basket. The 1:9–1:10 concentrate ratio is intended for drinking straight or with a small amount of hot water.
Troubleshooting
sour: Grind finer by ~22μm and ensure water is fully pre-boiled before loading the lower chamber. SL28's cranberry note is already citric-forward; sourness means the basket extraction was uneven or insufficient. Finer grind reduces channeling risk through SL28's large-bean bed and increases extraction yield toward the toffee sweet range.
thin: Add 1g dose or reduce water by 15g. Light SL28 has low solubility; Moka Pot's fixed pressure cannot compensate if the coffee-to-water ratio is too lean. Concentrating the dose is more effective than extending brew time, which can increase bitterness rather than extraction yield at Moka Pot's lower pressure.
strong: Reduce dose by 1g or add 15g to the lower chamber. Moka Pot's small volume means small dose changes have big strength effects. If the cranberry acidity becomes harshly overpowering rather than bright, diluting slightly with hot water after brewing is the most controlled approach to finding the right strength.
French Press at 76/100 for this SL28 is a workable but not ideal choice, though it offers something that Chemex cannot: coffee oils remain in the cup, contributing mouthfeel that offsets SL28's naturally lean body profile. SL28's low yield variety—selected for quality over productivity—produces beans with concentrated acids and aromatic compounds, but the French Press's coarse grind at 960μm means extraction is inherently slower; the 4–8 minute steep compensates for what the reduced surface area can't achieve quickly. The grind is 40μm finer than the French Press default to account for the light roast's density. Temperature at 96°C is near-boiling, which helps push extraction on a dense bean that the coarse grind partially limits. The unfiltered cup will read differently from Chemex: toffee reads heavier and less transparent, cranberry is less precise and more diffuse, but body is meaningfully fuller.
Troubleshooting
sour: Grind finer by ~22μm. SL28's large, dense beans extract slowly in French Press; sourness means the 4–8 minute steep didn't reach the Maillard/caramelization compound range. Finer grind at an already-coarse French Press size is the lever with the largest impact on this dense, high-altitude bean. If already at the finer end, extend steep to the full 8 minutes.
thin: Add 1g dose or reduce water by 15g. Unlike paper-filter methods, French Press's metal mesh passes oils that contribute body—but light-roast SL28 still runs lean on dissolved solids. Extending steep time toward 8 minutes and waiting an additional 5 minutes after pressing for grounds to settle also increases effective extraction yield.
Cold BrewFlash Brew Recommended
Cold brew is not recommended for this bean. At near-freezing temperatures, cold water cannot extract the complex acids, delicate aromatics, and bright fruit compounds that define a light-roasted coffee — they remain locked in the cell matrix. For a cold version of this coffee, use flash brew: brew a concentrated pour-over (V60 or Chemex at 60% of the normal water volume) directly over ice in the server. The hot water extracts the full flavor spectrum, and the rapid ice cooling locks in volatiles that would otherwise evaporate during a slow cool-down.