What coffee should I buy for cold brew?

Cold brew — cold extraction over 12 to 24 hours — is a method that amplifies sweetness, tones down acidity, and concentrates the coffee's natural sugars. You need a coffee that benefits from these characteristics: medium roast, coarse grind, and naturally chocolatey, fruity, or sweet origins. Very light roasts produce unpleasant cold acidity; very dark roasts become overwhelmingly bitter over a long steep.

The chemistry of cold brew is fundamentally different from hot extraction. At low temperatures (4-20°C), chlorogenic acids — responsible for the acidity perceived as aggressive in an over-extracted hot coffee — are far less soluble. The result: cold brew is naturally less acidic, smoother, and richer in natural sugars. This property completely changes the coffee selection criteria.

The first criterion is roast level. A medium roast (light-medium to medium) is ideal: it preserves the fruity and chocolatey aromatic compounds that dissolve well in cold water. However, too light a roast will still produce unpleasant residual acidity even cold — because some organic acids (malic, citric) remain soluble at low temperatures. Too dark a roast releases bitter compounds (phenols, degraded chlorogenic acids) during long extraction that dominate and weigh down the cup.

The second criterion is origin. Naturally sweet and low-tannin coffees are the best candidates. Brazil (cerrado, south Minas arabica) — with notes of milk chocolate, nuts, and caramel — is the archetype of a cold brew coffee. Colombia (balanced profile, fruity sweetness) works very well. Natural process Ethiopia brings red fruit and berry notes that are highly appreciated. Sumatra (wet-hulled process) yields a thick, earthy, spicy cold brew. Conversely, highly floral and acidic coffees (some washed Kenyan or high-altitude washed Ethiopian) can taste flat or unbalanced in cold brew.

The third criterion is grind size. Cold brew requires a coarse grind — comparable to French press or slightly finer. Too fine a grind in a 12-24h extraction causes over-extraction even cold, making the cup bitter and tannic. The recommended coffee-to-water ratio is generally 1:8 to 1:10 for a concentrate (to be diluted) or 1:14 to 1:16 for direct consumption.

Finally, freshness matters, though cold brew is slightly more forgiving of a somewhat aged coffee than hot extraction. A coffee roasted 2 to 6 weeks ago (slightly off-gassed) is often ideal — too fresh, and residual CO2 can disrupt cold extraction.

Selecting for cold brew's unique extraction chemistry

Cold brew's low-temperature extraction (4–20°C over 12–24 hours) selectively extracts a different compound profile than hot brewing — high-solubility organic acids and certain volatile aromatics dissolve much less efficiently at cold temperatures, producing a cup characterised by low acidity, heavy body, and elevated sweetness relative to the same coffee brewed hot. This selectivity means coffees that taste balanced and complex as hot filter coffee may taste flat and one-dimensional as cold brew, because the brightness and floral notes that made them interesting require hot water to express. Coffees that make excellent cold brew are those whose positive characteristics — sweetness, body, chocolate and nut notes — express well at low extraction temperatures without depending on the volatile aromatics that cold brewing suppresses.

Brazilian naturals, Colombian medium-roasted coffees, and Guatemalan high-altitude coffees consistently perform well as cold brew bases because their dominant flavour families (chocolate, caramel, gentle fruit, moderate sweetness) survive the cold extraction conditions. Ethiopian naturals can produce interesting cold brew — the intense fruit compounds that characterise natural process coffees are more heat-resistant than washed coffees' floral notes and can persist into cold brew in modified form. The result is a cold brew with a fruit-jam quality rather than the fresh fruit brightness of hot-brewed Ethiopian naturals — not better or worse, but characteristically different and appreciated by drinkers who find cold brew's usual chocolate-forward profile monotonous.

Going deeper

Roast level for cold brew follows a slightly different recommendation than for hot brewing. Many specialty cold brew recommendations suggest medium to medium-dark roast rather than the light roasts that dominate specialty filter brewing, because the lower extraction efficiency of cold brewing means lighter roasts — which require more energy to extract their full flavour potential — underperform relative to their hot-brewing quality. A medium-dark roast designed for cold brew produces lower perceived acidity (because both the roast development and the cold extraction reduce acidity simultaneously) and heavier body that reads well as a chilled beverage and survives ice dilution or milk addition. This is one of the few contexts in specialty coffee where darker roast levels are genuinely recommended over lighter ones.