FAQ

Pick a single 100g of a recently roasted (within ~2 weeks) specialty single-origin at a medium roast. Central/South American origins like Colombia and Guatemala are balanced and beginner-friendly. A light-roast Ethiopia is a great second bag — it lets you experience fruity character.

Supermarket “commodity coffee” often mixes sources, prioritizes volume and is roasted long ago. Specialty states the origin, farm, variety and processing, and meets a quality bar of 80+ cupping points. It costs roughly 1.5–3× more, but the flavor resolution is on another level.

Generally they correlate, but judging on price alone is risky. A Best of Panama–winning Geisha can be tens of thousands of yen per kg, yet may not match your taste. There are plenty of excellent beans in the ¥1,500–3,000 / 200g range. Prioritize “roast-date freshness” and “the direction of your own taste” over price.

Whenever possible choose whole beans and grind right before brewing. Ground coffee has far more surface area, oxidizes fast and loses aroma within days. If you have no grinder at home, have the shop grind it at purchase and use it within a week.

That’s a sign of under-extraction. Try one of: ① grind a little finer, ② raise water temp to 92–94°C, ③ extend pour time by 30 seconds, ④ add 1g of coffee. The trick is to change just one variable at a time and check the taste change.

That’s a sign of over-extraction. ① grind coarser, ② lower water temp by 1–2°C, ③ shorten brew time, ④ reduce coffee by 1g. Switching a dark roast to a lighter one is also an option.

90–93°C is the standard range. As a rule, lighter roasts like it hotter (93–95°C) and darker roasts cooler (88–90°C). 100°C straight off the boil causes harshness. Just pouring from the kettle into another pot naturally drops it 3–5°C.

A baseline of 1:15–1:17 (e.g. 15g coffee : 240g water). For stronger, 1:14; for lighter, 1:18. Espresso is around 1:2, French press around 1:14. Keeping the same ratio makes it easy to compare even when you change beans.

Yes. It prevents papery fibers from tainting the water and warms the dripper itself. About 10 seconds of hot water is enough. This step (“rinsing”) is standard in specialty coffee.

If you want to reproduce a great cup every day, a scale is essential — eyeballing makes the taste drift day to day. A ¥1,500–3,000 kitchen scale is plenty. A thermometer is the next step, and a kettle’s built-in temperature readout can stand in for it.

The peak is 2–4 weeks from the roast date. Within the first week, beans are still degassing and the taste can be unstable. After 4–6 weeks flavor declines. Be wary of beans with no roast date.

Generally not recommended. The fridge absorbs other food odors, and the freezer causes condensation on each in-and-out, speeding oxidation. Best is an airtight container in a cool, dark, dry place. Only if you won’t drink them for over a month, portion them, freeze, and grind “straight from frozen” — that’s OK.

A valve-equipped bag is fine as is (close the zipper firmly). For an ordinary bag without a valve, transferring to an airtight or vacuum container keeps them fresher longer.

About a week at room temperature, a month frozen. It degrades far faster than whole beans, so grind right before brewing whenever you can.

The FDA suggests up to 400mg/day for healthy adults (about 4 cups of coffee); up to 200mg during pregnancy. Individual sensitivity varies widely — cut back if you get insomnia or palpitations.

A common misconception — caffeine doesn’t change much by roast level. Per bean, light roast is slightly higher; measured by volume, dark roast is higher. The Arabica vs. Robusta difference (Robusta ~2×) matters far more.

It used to lose a lot of flavor, but today flavor-preserving methods like the Swiss Water Process and CO2 process are mainstream. A specialty decaf can be close in quality to a regular bean.

It stimulates stomach-acid secretion, so people with sensitive stomachs or reflux may feel safer avoiding it. Dark roasts are said to be gentler on the stomach because their chlorogenic acid has broken down.

Single origin is coffee sourced from one farm, region or country, letting you enjoy that origin’s distinct character. A blend mixes multiple origins for a stable taste. Beginners learn the differences between origins faster by starting with single origins.

An Arabica variety originally from Ethiopia that stunned the world at a 2004 Panama auction. It’s known for vivid floral aromatics like jasmine, bergamot and peach. Rare and expensive (thousands of yen per 100g), but it offers an experience beyond what you thought coffee could be.

African (Ethiopia, Kenya): fruity, floral, bright acidity. South American (Brazil, Colombia): balanced, chocolate, nutty. Central American (Guatemala, Costa Rica): delicate, citrus, sweet. Asian (Indonesia): heavy body, earthy, low acidity.

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For now it’s stored locally per device. You can export/import as JSON from “Your data” in the settings screen, so use that when you switch devices.

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