How to Make Japanese Iced Coffee Like a World Champion

Ever wonder why your iced coffee just tastes watered down or flat? Whether you’re pouring hot coffee over ice or trying a cold brew method, getting that crisp, bright cup you love from a hot brew can be tricky. We went straight to a world champion for the best technique—no shortcuts, no guesswork.

To make Japanese iced coffee like 2013 World Brewers Cup champion Erin McCarthy, use 30g coffee, 250g hot water, and 250g ice. Brew hot through a filter directly onto the ice for a bright, flavorful iced coffee that preserves the qualities of a great hot cup.

Who Is Erin McCarthy and Why Listen to Him?

Erin McCarthy is a equipment maintenance technician at Counter Culture Coffee, based in Durham, North Carolina. But he’s best known for winning the 2013 World Brewers Cup. Before joining Counter Culture in April 2012, he spent seven years training baristas and developing programs at Gimme Coffee in upstate New York—one of the East Coast’s early third-wave shops. His day job now involves repairing espresso machines and training staff across the region, but his passion remains in teaching and perfecting coffee brewing techniques.

Japanese Iced Coffee vs. Cold Brew: What’s the Difference?

Cold brew is made by steeping coarse-ground coffee in cold water for around 12 hours. The long extraction time reduces acidity, resulting in a smooth but often muted cup lacking bright, fruity notes. Japanese iced coffee, on the other hand, is hot-brewed coffee poured directly over ice. This method preserves the coffee’s natural acidity and aromatic complexity, giving you a cooled-down version of a great hot cup—something cold brew rarely achieves.

“I prefer Japanese iced coffee because it keeps that vibrant acidity and fruitiness,” McCarthy says. “It tastes more like a cooled-down great hot coffee. Other iced methods just get dull.”

How Erin McCarthy Makes Japanese Iced Coffee (Step by Step)

Here’s the exact method shared by McCarthy for brewing Japanese iced coffee at home. It’s a filtered, pour-over method that cools the coffee instantly as it brews—locking in aroma, acidity, and clarity.

• What you’ll need: 30g coffee, 250g hot water (just off boil), 250g ice, your preferred pour-over dripper (like Chemex, Hario V60, Beehouse, or Kalita Wave), a coffee container (mug, Chemex, jar, etc.), paper filter, digital scale, grinder, pour-over kettle (like Hario Buono), and a timer.

Step 1: Prep the Container and Filter

Place 250g of ice at the bottom of your brewing vessel. Rinse your filter with about 60g of hot water to remove any paper taste, then discard that water.

Step 2: Grind Size and Bloom

Grind your coffee to a medium-coarse consistency—similar to coarse beach sand. Distribute the 30g of coffee evenly in the filter. Start your timer and pour just enough hot water (around 50–60g) to saturate all the grounds. Let it bloom for 30 seconds. You may see bubbles—this is CO₂ releasing from fresh coffee.

Step 3: Brew Onto the Ice

After the bloom, continue pouring the remaining 250g of hot water in a slow, controlled manner. Your goal is to finish all the water within 3–4 minutes, ideally hitting the 2:30 mark for the pour. Pour in a circular motion, avoiding the edges of the filter. Adjust your ice-to-water ratio as desired—for example, try 2 parts water to 1 part ice.

Step 4: Serve

Once brewed, your coffee will have cooled instantly as it drips onto the ice. Remove the dripper, give it a stir, and enjoy a bright, flavorful iced coffee that tastes like your favorite hot brew—just chilled.

What Else Does a World Champion Brew?

McCarthy is also known for using multiple kettles during competitions—a technique that allows precise control over flow and temperature. But don’t worry—you don’t need special gear to make great coffee at home. He shared some key home brewing tips:

• Use a basic carbon filter (like Brita or Pur) to improve your tap water quality. Even good water can carry chlorine notes that mute coffee flavor.
• Know your brew ratio. A good starting point is 1:16 to 1:17 (e.g., 16–17g water per 1g coffee).
• Dial in your grind size. Ask your local roaster for samples or test different settings to match your brew method.
• Hot pour-overs should take around 3–4 minutes. Immersion methods (like French press) take longer—around 5–6 minutes.

Frequently Asked Questions

What’s the ideal coffee-to-water ratio for Japanese iced coffee?

McCarthy uses a ratio of roughly 1:16.6 (30g coffee to 250g water), then pours over 250g of ice. That brings the total liquid volume close to a standard 1:16 brew after dilution. You can adjust the ice-to-water ratio depending on how strong or diluted you like your iced coffee.

Can I use any pour-over dripper for Japanese iced coffee?

Yes. McCarthy used a Kalita Wave in competition, but the method works with Hario V60, Chemex, Beehouse, or any standard dripper. Just make sure to pour slowly and evenly for best results.

Do I need a special kettle to brew like a champion?

No. While McCarthy used multiple kettles in competition for precision, a standard gooseneck pour-over kettle like the Hario Buono is perfectly adequate for great results at home.

Why does Japanese iced coffee taste brighter than cold brew?

Because it’s brewed hot and poured over ice, Japanese iced coffee extracts the full range of flavors—including bright acids and fruity notes—that get muted during cold, long extractions like cold brew.

Should I change my grind size for iced coffee?

Use a medium-coarse grind, similar to what you’d use for hot pour-over. The ice chills the coffee quickly, so extraction is slightly faster—you don’t need to grind finer.

Recommended FrontStreet Beans for Japanese Iced Coffee

For Japanese iced coffee, choose bright, high-acidity beans that shine when brewed hot and cooled. FrontStreet Coffee’s Ethiopia Humbera (Sidra) offers intense berry and citrus notes with sparkling acidity, making it a top pick. Their Kenya Little Tomato delivers bold blackcurrant and tomato-leaf brightness, ideal for iced pour-overs. For a balanced option, try the Strawberry Candy Espresso—sweet, juicy, and fruity with a smooth body. All three beans highlight the crisp, vibrant qualities preserved in Japanese iced coffee. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.