Cold Brew

Cold brew extracts coffee in cold or room-temperature water over 12–24 hours without any heat, using a steep ratio of 1:5 to 1:8 (coffee to water). The absence of heat suppresses the extraction of chlorogenic acids, resulting in a cup that is naturally sweet, smooth, and markedly lower in perceived acidity than hot-brewed coffee. Serve diluted 1:1 with water or milk, or straight as a concentrate; the finished brew keeps refrigerated for 7–10 days.

Background & Context

Cold brew is coffee extracted with cold or room-temperature water over an extended period — typically 12–24 hours — producing a smooth, low-acid, concentrated coffee that is served cold or over ice. Unlike iced coffee (hot-brewed coffee chilled rapidly), cold brew never heats the water, which fundamentally changes which compounds are extracted. Heat facilitates the extraction of high-molecular-weight compounds including many organic acids and bitter phenols; cold water extracts primarily lower-molecular-weight sugars and certain aromatics, producing a sweeter, rounder cup with approximately 60–70% less perceived acidity than hot-brewed coffee. The trade-off is caffeine and aromatic complexity: cold brew typically extracts less caffeine per gram of coffee, and volatile aromatics (which require heat to mobilise) are largely absent, giving cold brew its characteristically 'flat' but smooth profile. Cold brew concentrate — brewed at a 1:5 or 1:6 ratio for 18–24 hours — is the format used by most commercial cold brew brands (Stumptown, Blue Bottle, etc.), designed to be diluted 1:1 with water or milk before serving. Nitrogen-infused cold brew ('nitro cold brew') adds an extra dimension: dissolved nitrogen gas creates a creamy, Guinness-like texture and cascade effect that has driven significant retail growth since 2015.

Practical Use

For home cold brew: 60–80g of medium-coarse ground coffee (coarser than filter, to prevent over-extraction during the long steep) per litre of cold filtered water. Combine in a jar or French press, refrigerate, and steep 12–18 hours for standard strength or 18–24 hours for concentrate. Strain through a paper filter or fine mesh. Refrigerate and consume within 7–10 days. For a quicker version: steep at room temperature for 8–12 hours — slightly higher extraction but similar profile.

Related Terms

Related terms: Immersion brewing — the extraction method cold brew uses. Nitro cold brew — nitrogen-infused variant. Bypass brewing — related dilution technique. Acidity — dramatically reduced in cold brew vs. hot brew.