Observations about the universe, life, Lausanne and me

Thursday, June 18, 2009

Bare-bones Vacuum Coffee

I think it was in Make-magazine #17 that I read about how to make your own vacuum coffee. Vacuum brewing is a very elegant (and not to mention tasty) method of preferring my drug of choice:

You heat water in a closed vessel, closed, that is, except for one (air-tight) connection to the jar with your coffee-grounds. The pressure of the boiling water will press it into the coffee-jar, where it will steep. When you remove the heat from the first vessel, the cooling water-vapour will contract, and air pressure will push delicious coffee back through the connection. Above you can see how commercial variants work, I built a rougher version diagrammed below:

It has the advantage of being sheap, easy to assemble, and you can conceivably burn down your house while making coffee! To build it, I used the following materials:

The hardest to get is no doubt the glass flask, I was lucky to get one from the lab for free (we are not allowed to use glassware anymore - too "dangerous" ). I don't have glass tubing yet, so I make due with some plastic tubing. Inelegant, but free. As a heat source I use a cheap blowtorch. The sieve  (making sure that the grinds don't clog the tube) in the coffee jar is a tea-filter, and the coffee jar itself is just a small bowl from my kitchen. Then there is of course my awesome coffee grinder.

 In assembling everything, make sure that the tube connecting the flask to the coffee jar reaches nearly to the bottom of both containers. As you can see, my filter doesn't enclose the tube at all, so I have to make sure that the coffee grounds does not overflow.

And then... the heat is on!

Soon, if everything is airtight, the water will climb the tube and gurgle into the coffee grounds.

Stir the coffee a bit, and leave the heat on the flask for a minute or so, so that the coffee has time to steep. Then remove the flame. The hot air/water vapour in the flask will take a minute or two to cool, and then...

delicious coffee will start to climb back into the flask!

Mmmhhh, coffee.


  1. Great work, I'm so honored that you were inspired by my MAKE article to do this!

  2. O-ho, a message from the Maker himself! Thanks for the praise, and for providing me with this excellent idea in the first place!

  3. A blend of the Napierian coffee maker and the better known Vacuum pots! Thank you for posting this, I am still poking at getting a vacuum pot but seeing this in "action" just looks like more fun to have than any oldoff the shelf vaccum pot!

  4. Yeah, it's fun, but I have to admit I use the setup only rarely, because it takes quite some time. Maybe I should look into getting a "real" vacuum pot!

  5. no shit i got 2 of them

  6. vacume pots that is. save the high schppl chemistry bs for cooking up some good old brain wave inhansing drugs.