What grind size do I need for cold brew?

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Accepted Answer

Coarse — even coarser than for French press. With a contact time of 12–24 hours, a fine grind would lead to severe over-extraction and bitterness. The ideal consistency is like coarsely cracked pepper. Cold brew is the brewing method with the absolute longest contact time: 12 to 24 hours. The coffee and cold water sit together overnight — making it an extreme immersion brew. The low water temperature significantly slows down the extraction process, but the enormous duration of the steep more than compensates for it. To achieve a balanced cup of coffee with such a long brewing time, the grind size must be correspondingly coarse. Large particles have a smaller relative surface area, which means the extraction happens much more slowly. This counterbalances the long steep time and prevents the cold brew from becoming bitter, harsh, or over-extracted. The ideal consistency is like coarsely cracked black pepper or small pebbles. It should be noticeably coarser than a French press grind — sitting at the absolute coarsest end of the grind spectrum. The individual particles should be highly visible to the naked eye and feel very chunky when rubbed between your fingers. Pre-ground coffee from the supermarket is almost always too fine for cold brew — it is generally calibrated for standard drip coffee machines. If you use standard medium grounds for cold brew, the result will be a bitter, over-extracted liquid that lacks the signature smoothness and sweetness that cold brew is known for. If you don't own a grinder, you should ask your local roaster to grind the beans extra coarse and explicitly state it is "for cold brew." A basic rule of thumb: the longer the steep time, the coarser the grind. If you only plan to steep for 12 hours, you can grind slightly finer. If you opt for a full 24 hours, you need to go extra coarse. By tweaking the grind size and the steep time, you can perfectly control the intensity of your cold brew. We don't have cold brew on the menu at Sophienstraße 27 at the moment. At home: grind as coarse as your grinder allows, steep for 16 to 18 hours, then filter through paper. The result is a mild, naturally sweet cold brew that works without sugar or milk. Feel free to drop by for a coffee — Green Wall Coffee, Sophienstraße 27 in Berlin-Lichtenberg, Mon–Fri 8am–5pm and Sat 10am–5pm.

What grind size do I need for cold brew?

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