Vacuum Brewer
Views
From TMC Wiki
Contents |
[edit] Vacuum Brewer
The vacuum brewer, or commonly called "vac-pot", is a coffee-maker that relies on pressure differences to brew the coffee.
[edit] Construction & Preparation
A vacuum brewer consists of two parts, a bottom and a top part. Water is added to the bottom part, and ground coffee to the top part. The two parts connects to each other through a tube that is usually attached to the top part, much like a funnel. This tube is also where the filter is added to keep the grounds from the final product. The top part, when inserted into the bottom part should completely seal the bottom part from the outside world with the exception of the connecting tube, which is where the water and the brewed coffee will pass through.
When the brewer is fully loaded the bottom part is added onto a heat source (gas or alcohol burner/stove) and the process stats.
[edit] Brewing Process
First the water in the bottom part begins to boil, which builds up steam pressure in the bottom part. This pressure has nowhere to go, so it starts to force water up through the connecting pipe. As heating continues, all the water is forced to the top chamber, where it mixes with the coffee grounds.
At this point the coffee brewer operator might stir the grounds in the top part to promote extraction.
When brewing is considered complete (this point is determined by trial and error) the heat source is removed and the top part begins to cool. This results in a decreased pressure in the bottom chamber, which creates a vacuum, which sucks the coffee through the filter and connecting pipe into the bottom chamber. The grounds are filtered out at the same time, and stays in the top chamber. The top and connecting pipe is removed, and the bottom chamber is full of coffee.
[edit] Notes
Some of the benefits to this method is the way it regulates brewing temperature. As the water rise in the connecting tube it also cools down from boiling to something quite close to the optimal brewing temperature, 92 degrees centigrade.