A centrifuge is a useful tool that has gained an increasing interest for kitchen applications the last couple of years. Famous chefs, like Heston Blumenthal and Andoni Luis Aduriz (Mugaritz), have used it for years and also reference to it in their cookbooks for some recipes.
So what can you then do with a centrifuge (aka fuge)? Basically it is a very effective tool for filtering/separation by the use of gravity. A centrifuge use rotational forces to separate food into layers by density:
- Denser components (e.g. solids in a tomato purée with a higher density) sink to the bottom/towards the periphery (of the bottles used in the fuge).
- Less dense components (e.g. fats and oils) float to the top.
- Watery solutions resolve somewhere in between
Some practical examples:
- You can separate sharp tasting pulps from a juice providing a layer of sweet good tasting juice not easily achieved by other methods. A couple of examples are juice made of carrot or pea.
- You can have a crystal-clear consommé made by a far amount of less effort than if you use traditional methods
- Clarifying juices to be able to carbonate drinks (more details: Liquid Intelligence)
- Blend liquors and fruits and have a clear flavour marinated spirit (eventually with the help of some enzymes).
- Making herbal- and nut oils.
- Concentrate purees.
- Make pea “butter”. This can not be done without a centrifuge and Modernist Cuisine were the first one doing this. Fantastically sweet. More details here. Also, with the remaining pea water, you can also do an fantastic green pea soap.
- Make no-churn butter. More details here.
Note: for more food and drink related suggestions I recommend you to check out Dave Arnolds (a pioneer in using the fuge in the kitchen and bar) excellent book Liquid Intelligence (not only for fuge applications) and spinzall.com (also; see my update in the end of this post). Also, the Modernist Cuisine (the “big” five volume one) has some applications for the centrifuge.
I was for instance making a Caprese salad with a twist were some tomatoes used were made semi-transparent by the help of a centrifuge (see pic below).
So what should you consider when buying a centrifuge? From a pure functional perspective there are three main features to consider:
- Cooling (refrigeration) capacity (or not)
- Volume capacity (i.e. what is the maximum total volume of food/juice etc. that could be used in the centrifuge bottles)
- Maximum g-force (i.e. times the Earth’s gravity) of the fuge. For instance a centrifuge capable of providing 10000g means 10000 times higher gravity the Earth’s gravity (which is 1g). (Also referenced to as RCF)
Unfortunately, most of us also need to take the following constraints into consideration when deciding what centrifuge to buy:
- The price of the centrifuge, rotor and bottles (and eventually adapters)
- The size (floor-space, weight…)
The first feature can immediately be removed from the equation since you want a centrifuge with a cooling capacity (i.e. with a refrigerator). This though a centrifuge in many cases needs to be run for a period of several hours and this in combination with the friction created by the air (in the centrifuge chamber containing the rotor holding the bottles) not only can cause damage to the food from a pure taste perspective but also make it dangerous to consume.
For the two remaining functional factors (volume and g-force possible) you basically want those two figures to be as high as possible.
That said, for most people it is not possible to buy a very high a capacity (meaning both a large volume and a high RCF) centrifuge. First of all it is very expensive. The centrifuge used in the Modernist Cuisine cookbooks has a capacity (I think) of 3 liters and a g-force of (at least) 27500g in their recipes. A three (3) liter centrifuge capable of 27500g is out of reach for most chefs from a pure economical perspective (especially the home chefs paying for it themselves…). Also, a centrifuge having this capacity is very heavy and also occupies a large floor-space.
When I started to investigate what centrifuge to buy I was initially trying to follow the Modernist Cuisine numbers from above but it basically become to expensive, so I actually asked Modernist Cuisine what they recommended (in the book they recommend a 3 liter by 30000g fuge) and I got a good answer from Scott Heimendinger (known for running the seattlefoodgeek food-blog and who is now also working for Modernist Cuisine) who have used a centrifuge in his home for several years. To summarize he said that you should buy as high capacity you can afford but what you basically need for most application is a fuge capable of more than 1500g and at least a volume of 2 liters (his own home-fuge is capable of 1500g and 2 liter and he said the he could do most of the applications in the Modernist Cuisine with this).
So what is the constraint of running a centrifuge with, for instance, a capacity of 5000g, when the recipe suggests 27500g (as in the Modernist Cuisine recipes) and for example a running time of one (1) hour? A rough time estimate-translation is: 27500g/5000g * 1 hours which roughly equals a little bit more than five (5) hours in this case.
I also consulted Dave Arnold (cookingissues.com) for a second opinion and he also recommend opting for quantity/volume. Dave have several times in his radio program (on Heritage Radio Network) said that the sweet-spot for a restaurant in regards to the price/performance ratio for a centrifuge is:
- 3 liters capacity (i.e. a rotor supporting 3 liter). 3 liter usually translates to a configuration of 4x750ml bottles.
- 3000-4000 g
- Bench-top model
Worth noting is that Dave, with his extensive experience and expertise in using a centrifuge in the kitchen (and in the bar), often use something named Pectinex Ultra SP-L which is a specialty enzyme that breaks down the pectin structure. Typically used in juice manufacturing, Pectinex has several unique applications in the Modernist kitchen. It can be used to perfectly peel and supreme citrus fruit without using a knife. SP-L aids a lot in clarification of juices either with or without a centrifuge. Consequently, Pectinex (and other enzymes) could substantially decrease the run-time needed to clarify a juice in the fuge (or to put it differently; by using enzymes such as Ultra SP-L, the demands for a very a high g-force fuge is less demanding).
A centrifuge consists of the following parts:
The centrifuge itself. Two main models available:
- Floor-model (washing machine style) Bench-top model
Rotors (that holds the bottles in the fuge) could be of two different styles:
Swinging-bucket rotor Fixed angle rotor
Bottles and adapters
As can be seen in the left picture above there are four bottles in each adapter (i.e. the green part in the pic) and one adapter for each bucket in the swinging-bucket rotor. Another adapter option (for the same bucket and rotor) can be one holding only one bottle (large or small).
In general the swinging-bucket rotor can take bigger bottles but at a lower g-force in regards to the fixed-angle rotor (however, the really expensive high-capacity rotors are always fixed-angle ones but those centrifuges and rotors are out of the questions for most kitchens from an economical standpoint).
As the name indicate, the swinging-bucket rotor, will have the bottles “swinging” out (when the centrifuge starts) and will in a moment after start have the bottles in an angle perpendicular to rotor axle (i.e. perpendicular to how the bottles are oriented in the left picture above). In contrast the bottles in the fixed-angle rotor will have a fixed angle all the time (i.e. the angle you can see in the right picture above). As a consequence of those two different design approches the resulting layers of the food/juice ends up differently in the bottles after the centrifugation for the two different rotors. The two schematic pictures below shows this difference schematically:
Swinging-bucket bottle Fixed-angle bottle
So which centrifuge did I finally opt for myself? I was initially opting for a Beckman-Coulter X30-R (R for refrigeration) which has a capacity of 1,6 liter and roughly 4000g but since both Scott and Dave recommended to go for a higher volume I finally bought a Beckman-Coulter X15-R with a rotor supporting a maximum of 3 liters (4x750ml) together with a maximum RCF of 5250g.
I also bought adapters for the rotor so I could also use 250ml bottles (e.g. 2x250ml or 4x250ml) and I have honestly not used anything else but the 250ml bottles. However, I have not had that much time yet to run and experiment with the fuge but I anyway think (for home usage and my personal needs) that I maybe should have gone for the smaller capacity one (supporting 1,6 liters which not only was less expensive but also had a smaller more convenient foot-print).
I bought a new one but I know that both Scott and Dave have bought used centrifuges. Dave bought his on eBay very cheap. If you buy a used on, it is important that you consider the following things:
- Centrifuges are foremost lab-equipment and probably not anything you could buy used from a kitchen. The fuge could therefore be contaminated and this is an issue of uttermost importance to address.
- Labs have been destroyed by centrifuge accidents and people have also died. A small crack, in the rotor for instance, invisible for the human eye to detect can have disastrous consequences and this is of course very important to check.
- Opt for volume (e.g. 2 to 3 liters) over high g-force
- 3000-4000g is good (but anything over 1500g is fine)
- Go for refrigeration
- If you buy a used one, be aware of its history (e.g. contamination and rotor status)
- Learn how to use enzymes (e.g. pectinase) together with the centrifuge.
UPDATE: Dave Arnold has developed and designed a centrifuge specifically for kitchen and bar applications. This centrifuge is fundamentally different in comparison to the ones described above (i.e. that are the ones present on the market today…). Not just much less expensive (currently $799, but for the moment they do not accept any more pre-orders), but also with a much smaller footprint and lower weight. Dave has ran a crowd funding campaign (that ended January 31, 2017) and have now decided to manufacture this new centrifuge. Check out this site for more details: spinzall.com
Excellent guide and exactly what I was looking for. I sadly have been spoiled by working in a lab and having access to nice centrifuges all the time, so looking to buy one has really opened my eyes to their cost. One day I will own one…
I was just on the Chef Steps website thinking about buying a centrifuge and you wrote up exactly the document I needed. Thank you!
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I LOVE it!!! That is so amazing!! At what speed did you centrifuge your tomato’s to get them semi-transparent? What rotor did you use? etc. I would love to do this and freak out my husband 🙂 lol I work in a molecular biology lab.
I am almost always using the maximum speed (i.e. g-force) of the centrifuge for all applications (which I think most people do). My fuge is capable of achieving 5250 g.
What I do change however is the time I run the centrifuge and this is related to what kind of “subject” you want to separate. In regards to have the tomatoes semi-transparent for instance, I only need to run it for about 20 minutes.
For other tasks, you need to run the centrifuge for much longer time. And sometimes it is not possible to have something separated with a fuge capable of 5250 g that I have. That said, you could anyway use a fuge with the capabilities of the one I have (i.e. one capable of 5250 g or lower…) for almost all kitchen purposes. What you need instead, is for instance Pectinex Ultra SP-L, which is a specialty enzyme that breaks down the pectin structure, and makes it possible to use a fuge with less “power” (see more details in my article above about this).
Another example on the same topic: If you want to clarify something of high acidity (e.g. lemon or lime juice) you are not able to do this straight forward with my centrifuge. However, if you use two commonly available wine clarification aids named Kieselsol and Chitosan (you can buy them in most home-brew shops and also on amazon) you can clarify for instance lemon juice without any problem with the fuge I have (and also centrifuges with lower specs for that matter)
To finish your questions: I am using a swinging-bucket rotor.
Here are all the steps:
1) Use fresh tomatoes that are first peeled
2) Puree the peeled tomatoes in a blender
3) Filter puree through a sieve
4) Remove the air (given by the blending) of the filtered tomato puree (e.g. by using a vacuum chamber or just let it rest in the fridge for some hours)
5) Centrifuge for 20 minutes (at 5250g or the highest setting of my machine).
6) Use kappa carrageenan to achieve the jellification (kappa, though this gives the most transparent alternative, to my knowledge).
7) Use a mold that gives the tomato spheres desired
apart of the buttermilk and peabutter, have you made anything recently?
I have mostly this summer been using the centrifuge to make different kinds of smooth juices and sodas. See http://www.chefsteps.com/activities/centrifuged-strawberry-juice for a juice example and http://www.chefsteps.com/activities/strawberry-soda for a soda illustration.
I am considering the Beckman X14R to separate fresh pressed coconut cream in order to get crystal clear raw coconut oil. What are your thoughts on this?
In general the Beckman X14R is having the specs (i.e. 3 liter capacity at 4300g and refrigeration) you wants (if you do not have an unlimited budget…) and live in US (i.e. 120 V only).
That said, I have never done centrifuged coconut oil myself (which is a pretty common product) and consequently do not know if there could be any problem with that specific application. I doubt that, and IF a higher force fuge is needed, you can in most cases instead use some tricks from the wine business (in regards to how they clarify) and still be able to use a fuge with less “power” (i.e. lower g-force). The specs of the X14R is easily on pair with most fuges used in the restaurant business.
aloha so whats the price for bench-top model?…new.
I bought my centrifuge a couple of years ago (new). Since the currency I purchased it in has lost its value a lot in comparison with both the Swiss- and US Dollar currency (Beckman-Coulter is a Swiss/US company), that price make no sense as of today. Beckman-Coulter only give out prices if you ask for a quote. That said, a quick browsing showed that the sticker price for a new one is around $12000 (i.e. for the Beckman-Coulter Allegra X-15R) without the rotor (which is about another $3000 for the SX4750 rotor). However, you NEVER pay the sticker price in this business and I would say that you easily will get 20% off this price without too much fighting.
much mahalo for your time and info.thats kinda what i was thinking on cost..ditto on the currency loss.well im open to getting a used kitchen model[not used outside of A kitchen] if anything comes up…
Hi and thanks for the information on centrifuge types. Very enlightening. I’m looking to buy a kitchen- type centrifuge with a swinging rotor to separate vegetable and fruit oils. Which centrifuge will you advice me to buy? I look forward to hearing from you. Many thanks. Funke.
Apart from the general guidelines (in the guide above); i.e. 2-3 liters, 3000-4000g and refrigeration I wonder if you will use it for home or commercial use (e.g. in a bar or restaurant? If commercial, I would withhold my recommendations. However, for home use, I should have opted for a centrifuge with a smaller volume. This, though you most certainly will not need the capacity in regards to volume and that, a lower volume fuge, is both less expensive and do also have a smaller footprint.
That being said, since it is now decided that the Spinzall centrifuge (spinzall.com) will be manufactured, I would have considered that an alternative (even though you said you were opting for swinging bucket fuge) and that basically for the same reasons (as for going for a lower volume one); a much smaller footprint and cheaper price.
If you still want to go with an ordinary centrifuge (i.e. not the Spinzall, but a swinging bucket one), I have personally good experiences with the brand Beckman Coulter. However, there are a lot of other manufactures/brands with similar performance.
Very good information here; thank you for continuing to update this page. There is a lot of discussion about the appropriate size, and I have a question in that regard. Is there some importance to having all tubes inside the machine the same weight before starting the spin cycle? If so, does that mean that if one purchases a machine with a 3L capacity, that you must always fill up 3 liters? Do you need to always use all 6, or 8 or all the tubes in the holders? Or, I suppose perhaps you simply need to fill each tube with the same amount and that could be a small amount of material? Also, how you would compare the versatility of a centrifuge to a rotary evaporator if one could only afford to purchase one machine? thanks
The discussions in the guide, on the topic of volume, is regarding the maximum volume (“size”) possible. In other words; you do not need to centrifuge a full 3 liters (if that is the maximum capacity) if you are only interested in processing, for example, 1 liter (i.e. you can centrifuge a smaller volume than the maximum volume). That being said: you always need to balance the centrifuge and this is of uttermost importance!
To balance a centrifuge, put samples in the centrifuge (i.e. in the bottles located in the rotor) so they are directly across from each other (and having the same weight). If you only have one tube to centrifuge (e.g. with 500 grams of juice), you should balance it with a “blank” tube (a tube filled with water, and in this example, 500 ml of water). However, you could also put 250 gram of juice in one tube and 250 grams in the tube opposite the other (i.e. directly across the other).
More details and instructions for balancing a centrifuge (i.e. rotor) could be found here: http://se.beckman.com/centrifugation/principles/balancing-your-rotor
Its very mice article indeed and very useful for me.
In bottom line: what does it mean (3) go for refrigeration?
Any type or brand recommendations (same capacity i guess) for Bar use apart of Spinzall?
I have a centrifuge from Beckman-Coulter myself, which I am happy and satisfied with (and have the spec specified above). That being said, there are a lot of other brands, e.g. Thermo Scientific. I think that the specs (from above) is more important to follow than a specific brand.
When you run a centrifuge (in many cases for several hours) at several thousands of RPM (revolutions per minute), this causes a friction created by the air (in the centrifuge chamber containing the rotor holding the bottles). This friction causes heat, that can not only cause damage to the food, from a pure taste perspective, but also make it dangerous to consume. Therefore, refrigeration is preferred (to counteract the heat created by the friction).