How to Brew Cold Brew Coffee with the Hario Mitsudashi

The Hario Mitsudashi Cold Brew Coffee Pot is a simple, reliable way to make smooth cold brew at home. This guide uses the 1-liter pot and includes exact grind guidance for the 1Zpresso K-Max Ultra, storage best practices, and why an optional paper filter can improve clarity and shelf life.

What You Need

• Hario Mitsudashi 1L cold brew pot
• Freshly roasted coffee, medium-coarse grind
• Filtered water
• Kitchen scale (recommended)

Ratio

Start here and adjust to taste:

• 80–100 g coffee
• 1,000 ml water

80 g = lighter, tea-like. 100 g = stronger, more concentrated.

Grind Size for 1Zpresso K-Max Ultra

Target a medium-coarse grind, similar to French press. On the 1Zpresso K-Max Ultra, use the 9-10 setting. This is essentially one full turn and one extra notch if needed. This yields a coarse, even grind that avoids muddiness while extracting well during an 8–12 hour steep.

Tuning: If the brew tastes dull or weak, go slightly finer or increase coffee dose. If it’s bitter or muddy, go coarser or reduce steep time.

Step-by-Step

1. Grind. Weigh 80–100 g beans. Grind at ~50–60 clicks on the K-Max Ultra.
2. Load. Insert the Mitsudashi mesh basket and add the grounds. Level with a gentle tap.
3. Saturate. Pour ~200 ml water over the grounds to wet everything evenly. Wait 1 minute.
4. Top up. Add water to reach 1,000 ml. Optional: gently stir inside the basket for a stronger extraction.
5. Steep cold. Lid on. Refrigerate 8–12 hours.
   Less time = lighter. More time = richer.
6. Remove basket. Lift out the filter and let it drip a few seconds back into the pot.
7. Optional polish. For maximum clarity, pass the brew through a paper filter (details below).

Storage: Keep It Fresh

• Transfer immediately to a hermetic glass bottle (swing-top or airtight carafe). This limits oxygen exposure and flavor drift.
• Store in the fridge at 4 °C. Best within 3 days. Acceptable up to ~5 days if kept airtight and cold.
• Minimize headspace. Fill bottles close to the neck or split into smaller bottles.

Why hermetic? Oxygen drives staling. Airtight storage slows oxidation, preserves aromatics, and maintains sweetness.

Why Add a Paper Filter Pass

The mesh basket leaves fines and oils in suspension. A quick pass through a paper filter after steeping:

• Increases clarity by removing fines for a crisper, cleaner cup.
• Reduces bitterness at the tail by absorbing some oils and ultrafines.
• Improves stability slightly. Fewer suspended particles and oils can slow flavor degradation in the fridge.

If you prefer a heavier body and more “coffee presence,” skip the paper step.

Bean and Roast Guidance

• Single origin for fruit and florals. Blends for chocolate and nuts.
• Medium roast is the safe default. Dark roasts can feel heavy in cold brew; go coarser or shorten steep if using them.

Fast Troubleshooting

• Too weak: finer grind, longer steep, or +10 g dose.
• Too bitter/muddy: coarser grind, shorter steep, or −10 g dose.
• Flat by day 2–3: ensure hermetic storage, reduce headspace, consider paper filtering.