Hybrid · hard
Siphon (Vacuum Pot)
A siphon uses two glass chambers. Heating the bottom bulb pushes water up into the top chamber, where the coffee steeps at a steady temperature. When you take the heat away, the cooling bulb pulls the brewed coffee back down through a filter. It's fussy and a bit theatrical, but it gives a clean, tea-like cup with very stable brew temperature.
20 gCoffee
300 gWater
1:15Ratio
88-93 °CTemp
2:30-3:00Time
medium-fine, a bit finer than dripGrind
Water by roast: light 93 °C · medium 91 °C · dark 88 °C
Steps
- PrepSoak a cloth filter in warm water for 5 minutes, or rinse a paper filter, then hook it into the top chamber
- PrepFill the bottom bulb with 300 g hot water from the kettle and set it over the heat
- PrepSeat the top chamber when the water nears a boil and let the water rise
- PrepTurn the heat down so the water in the top sits around 88-93 °C
- 0:00Add 20 g coffee and gently submerge it with the paddle
- 0:30Give the crust one more gentle stir
- 1:15Remove the heat and stir 5-10 timesThe cooling bulb pulls the coffee down
- 2:30Drawdown done, a neat dome of grounds should sit on the filter
Variations
Blue Bottle SiphonBlue Bottle Coffee
Slightly cooler brew water, undisturbed 1:10 steep, then ten brisk stirs off the heat.
22 g · 300 g water · 85-91 °C · sea salt, a little finer than regular drip
- PrepSoak the filter at least 5 minutes, hook it into the hopper
- PrepFill the bulb with 300 g hot water, insert the hopper and heat until water rises
- PrepTurn the heat down so the water holds at 85-91 °C
- 0:00Add 20-25 g coffee and gently but fully submerge it
- 1:10Remove from heat in one motion and give 10 stirs
- 2:10Coffee has drawn down, remove the hopper and let it cool a few minutes
Sprudge Siphon (Hario TCA-5)Sprudge
Larger 5-cup batch with paper filter, a full 2-minute steep and a gentle back-and-forth paddle during drawdown.
35 g · 560 g water · 93 °C · medium, like beach sand
- PrepHeat 560 g water in the bottom globe on high, rinse the paper filter assembly
- PrepWhen small bubbles form, seat the top chamber; lower the flame as the water rises
- 0:00Add 35 g coffee and paddle gently back and forth to saturate
- 0:30Give the crust another gentle stir
- 2:00Turn off and remove the burner
- 2:15As drawdown starts, give one gentle back-and-forth paddle
- 3:30Drawdown finished, about 1:30 after removing heat
Fix your cup
| Taste | Cause | Fix |
|---|---|---|
| Sour, thin | Under-extracted or water too cool in the top | Grind finer or keep the flame a little higher |
| Bitter, harsh | Over-extracted or too much heat | Grind coarser, lower the flame, shorten the steep |
| Drawdown stalls | Grind too fine, too many fines or too aggressive a stir | Grind coarser, stir more gently |
| Muddy cup | Filter not centred, grounds slipping past | Re-seat the filter so the chain hook is tight and centred |
| Water won't rise | Seal not tight | Twist the top chamber firmly into the bulb |
Tips
- Pre-heat the water in a kettle. Heating cold water with a spirit lamp takes ages.
- Check temperature in the top chamber with a thermometer. Once you know where your flame needs to be, you can skip it.
- Stir gently. Hard stirring drives fines into the filter and slows the drawdown.
- Cloth filters give more body. Paper is easier to live with and gives more clarity.
- Keep a used cloth filter wet in a sealed container in the fridge and replace it when it starts to smell.
- Let the coffee cool a few minutes before drinking. Siphon coffee comes out very hot and tastes flat until it drops a bit.
Common mistakes
- Putting the top chamber on a dry or cold bulb over a flame. Thermal shock can crack the glass.
- Leaving the flame on high once the water has risen. The brew water ends up close to boiling.
- Forgetting the little bit of water that stays in the bulb. It's normal, don't chase it.
- Not cleaning cloth filters properly, which gives a stale taste to every brew after.
What you need
- Siphon brewer (e.g. Hario Technica TCA-3 or TCA-5)
- Heat source (alcohol lamp, butane burner or halogen)
- Cloth or paper filter
- Bamboo paddle or spoon
- Scale
- Kettle
- Thermometer
- Timer