Percolator

The operating principle behind a percolator is to get boiling water (and steam) through the coffee ground placed above the pot, in a basket, until all the flavors have been washed; the resulted coffee flows back into the pot.

The main components of a percolator are the pot, the lid, the funnel, the filter basket and the filter top.

When using a percolator, it is recommended to grind coffee more coarsely. Otherwise, the coffee will be over-extracted, bitter tasting and will precipitate to the bottom of the cup.

Percolators can be stove-type (stainless steel or glass percolators) and the electric type. Urns are percolators using the same brewing procedure, but of higher capacity.

Vacuum Coffee Maker (French Press)

The Vacuum coffee makers (or siphon brewers) are non-automatic appliances. Though a kitchen appliance, a vacuum coffee maker can be easily mistaken to be chemistry lab equipment. It consists of two overlapped glass bowls (containers) that communicate through a siphon tube; the upper container has at its bottom a filter (cloth, metal, glass, or plastic and paper mixtures).

There are four types of vacuum coffee makers.

The two globe type, which was first provided by Silex, an American company and dates back to the 1920s.

The balance type brewer, which works on the same principle as the two globe brewer, only it has two chambers placed side by side.

The Napier (or the one way) vacuum brewer, which is less common.

The modern-automatic type

Drip Coffee Maker

Drip coffee makers range from a single serve to extra large capacity pots. They have a capacity to heat the water properly.

Drip coffee makers can be manual or automatic. The difference is that the automatic machine warms the water while in the manual drip you have to prepare the hot water separately. Programmable drip coffee makers can also be found in the market. These machines are useful for those who use morning coffee as a kickstart. All you have to do is prepare the drip coffee maker in the evening (water and coffee in it) and program the machine. It will make fresh coffee the morning, at the hour you requested.

Espresso Machines

When we talk of the espresso machines, we are thinking of four major types:

The manual espresso machine which have smaller water reservoirs, and can be noisy during initial heating.

The semi-automatic or the electric pump espresso machine, where pressure is not provided by hand but through an electric pump. You can decide when the brewing process starts, by turning on a knob. You can also decide the end of extraction, by switching in the opposite direction. Dosing, tamping and removing the grounds are however, still carried out manually.

The fully automatic espresso machine or the one-touch system is very similar to the semi-automatic machine, with one small difference. You just decide when the brewing starts, and the machine will stop itself, after a predefined time.

The super automatic espresso machine is just that, superautomatic. These convenient appliances do almost everything, from grinding to dosing, tamping to brewing. Super automatics allow you to do whatever you want while the coffee is being prepared.

Of course, there are also steam-driven machines, the cheap type, but they do not produce enough pressure to extract and brew real espresso.