What is a vacuum coffee maker?
They work as their name suggests; a syphon which uses pressure and vapour to make the coffee. They produce the base for ‘long’ coffees as opposed to espressos.
Heating and cooling the bottom chamber (water) creates various amounts of pressure. If sufficiently heated, the water rises up into the upper chamber, and then with cooling and taking it off the heat source, it drops back down into the lower section.
In the upper chamber, the ground coffee is held, which mixes with the water. The coffee grinds don’t pass through to the coffee mixture because of the filter contained in the stem of the coffee ground container/upper carafe.
Balance vacuum coffee makers work slightly differently in that both parts are horizontally connected via a tube. The water passes through from the metal boiling flask, into the glass carafe containing the granules, and then back again once brewed. The idea is essentially the same (and if anything, a lot more traditional).
How to choose the best vacuum coffee maker
There isn’t a massive difference between a lot of the vacuum coffee makers on the market. Most are a similar size capacity-wise and can use most heat sources bar induction hobs.
The Bodum Pebo is one of the largest if you want to entertain a lot of people at once, and the balance vacuum coffee makers are the best by far for looks and creating a talking point.
It all boils down to your budget, which you like the look of and which sounds most practical for your coffee drinking lifestyle, as well as which can be stored best in your kitchen (or displayed).
In general, the rate is pretty standard, hovering around the £40/£50 mark for most standard 5 cup models. Some may increase up to £100 if the materials are slightly stronger or capacity is larger, and balance models are also higher priced.
Most include an ethanol burner with the purchase, so all you need to do is buy the fuel and coffee granules. These burners provide the perfect level of heat and flame intensity, but you may want to purchase a butane burner or use your hob if you want to control the flame.
Certain parts of the vacuum machines may need replacing over time, but generally, these parts are not expensive. Most come with reusable cloth filters, but you may prefer to use paper filters which will need replacing after every use.
Most of the products reviewed come with a cloth filter. This is a nod to the original design, and they are reusable as they can be cleaned after every use which only improves the fact they are eco-friendly.
Most are also usable with disposable paper filters if this is something you prefer, although you may need to buy an adaptor for these. If you prefer a stronger taste, a metal filter may be the best bet. These pass through more oils than cloth or paper (which absorbs them), but are still reusable and just need to be cleaned after every use. They may even last longer than the cloth alternatives over the months. Again, an adaptor may be required.
They all use ground coffee. It is recommended the grinds aren’t too fine as this could block the filter, but also not too coarse so maximum extraction can be achieved.
You can either buy them pre-ground or purchase a separate grinder. If buying them ready-made, look for blends which are suitable for use in filter machines.