The principle is very simple: the chosen fruit is fed into the top of the machine through a pipe called a "chimney".
The fruit is washed, but not peeled as this is not necessary. They are pulverized by a grater which rotates at very high speed (green arrow), the pulp obtained is thrown against a very fine grid where the juice is extracted by centrifugal force (hence the name), the "dry" pulp is ejected at the rear into a collection tray (blue arrow), and the precious juice is collected in a pitcher (red arrow).
Note that the resulting juice is very, very frothy, and you'll need to wait a few minutes for it to settle before the froth rises to the top and the (clear) juice settles to the bottom.
Selection criteria
There are all sorts of centrifuge models and brands to choose from, and having hesitated a great deal before taking the plunge, I'd like to give you the points I consider important, or not, in making your choice.
What's important
- Power and speed: these determine the machine's capacity and efficiency. To be efficient, it needs to turn very fast (8,000 rpm minimum), and be powerful (500 watts minimum) to avoid jamming during operation.
- The recovery pitcher: This essential element receives the juice that flows from the centrifuge, and is designed so that when you pour, the foam remains in the pitcher and only the juice flows out.
- The pulp tank or pulp selector: A tank at the back of the centrifuge that receives the pulp from whatever you're juicing, it allows you to juice large quantities of fruit before having to clean the machine.
- The size of the chimney: The larger the chimney, the better, as it allows you to process whole fruits (apples, for example) without cutting them.
Not essential
- Centrifuge parts are dishwasher-safe, but cleaning by hand is easier and more effective.
- The centrifuge's spout can be raised to avoid dripping onto the work surface, which is just handy.
- Several rotation speeds, although we always use the maximum speed.
- Citrus juicer function, but of little interest.
To sum up
- 500 Watts, 800 rpm minimum
- Recovery pitcher
- Pulp bin
My choice
Based on these criteria, I opted for a Philips HR 1858, which I bought for around €150 in 2010. I'm very happy with it, although it broke down after 1 month and was sent to the after-sales service for 3 weeks...
But since then, it's been a real pleasure to use: Grany apple juice, for example, made in 1 minute, is simply divine!