Jump to content


Welcome to the eG Forums!

These forums are a service of the Society for Culinary Arts & Letters, a 501c3 nonprofit organization dedicated to advancement of the culinary arts. Anyone can read the forums, however if you would like to participate in active discussions please join the Society.

Photo

Cooking with Liquid Nitrogen

Modernist

  • Please log in to reply
189 replies to this topic

#91 paulraphael

paulraphael
  • participating member
  • 3,007 posts

Posted 14 May 2008 - 07:23 AM

So, I went off the deep end and bought a nitrogen dewar on ebay. Now I need some nitrogen.

I've been reading things like, "oh, yeah, just go to any welding or hospital supply place and they'll hook you up." But I'm not having much luck. Google is getting sick of me. Maybe I'm searching for the wrong terms?

Any thoughts? A pint of futuristic gelato (or one amateur wart removal session!) to anyone local with the answer.

Also: this dewar is a pressurized one and has a lot of aparatus attached to the top. Does anyone know about these thing? I'd like to find out if I need to do anything to make this safe (test any pressure relief valves), if any of the gadgets can be removed, etc.

Here's what it looks like:
http://cgi.ebay.com/...bayphotohosting

Edited by paulraphael, 14 May 2008 - 09:11 AM.


#92 Mikels

Mikels
  • participating member
  • 107 posts
  • Location:Connecticut

Posted 14 May 2008 - 08:42 AM

You can always find either liquid nitrogen or air (2 degrees warmer) at any university chemistry or physics department. They use the stuff like water for high vacuum lines. In the departments I have been in, they made it. I don't know what type of dewar you have, but make sure it can be used to bring it home.

#93 JimH

JimH
  • legacy participant
  • 366 posts
  • Location:Houston, TX

Posted 14 May 2008 - 11:01 AM

So, I went off the deep end and bought a nitrogen dewar on ebay. Now I need some nitrogen.

I've been reading things like, "oh, yeah, just go to any welding or hospital supply place and they'll hook you up." But I'm not having much luck. Google is getting sick of me. Maybe I'm searching for the wrong terms?

Any thoughts? A pint of futuristic gelato (or one amateur wart removal session!) to anyone local with the answer.

Also: this dewar is a pressurized one and has a lot of aparatus attached to the top. Does anyone know about these thing? I'd like to find out if I need to do anything to make this safe (test any pressure relief valves), if any of the gadgets can be removed, etc.

Here's what it looks like:
http://cgi.ebay.com/...bayphotohosting

View Post



Iif you have an Air Liquide branch near you they can tell you who they supply.

Edited because the link did not work, just Google Air Liquide

Edited a second time for stupidity.

Edited by JimH, 14 May 2008 - 11:13 AM.


#94 et alors

et alors
  • participating member
  • 206 posts

Posted 21 July 2008 - 08:54 PM

My husband had some liquid nitrogen lying around, so I decided we should make sorbet. We used a variation of an epicurious recipe with about half teh sugar so it wouldn't be too sweet. it was intense, fast and incredibly smooth, as everyone said. However, since my husband was on good terms with the nitrogen, we didn't fuss with gloves and such, we just treated it like we do the deep fat fryer. The rolling smoke with strange, like floating ice crystals as it floated over my bare feet.

Our two year old thought it was a blast.

Posted Image

see more

he got the LN4 at madco, a welding supply store.
"Gourmandise is not unbecoming to women: it suits the delicacy of their organs and recompenses them for some pleasures they cannot enjoy, and for some evils to which they are doomed." Jean Anthelme Brillat-Savarin

MetaFooder: linking you to food | @foodtwit

#95 Kerry Beal

Kerry Beal
  • participating member
  • 9,429 posts
  • Location:Ontario, Canada

Posted 22 July 2008 - 05:23 AM

Our two year old thought it was a blast.

Posted Image

see more

he got the LN4 at madco, a welding supply store.

View Post

What a delightful picture!

#96 et alors

et alors
  • participating member
  • 206 posts

Posted 26 July 2008 - 10:57 PM

thanks!

videos up. http://www.flickr.co...ack/2703582539/
"Gourmandise is not unbecoming to women: it suits the delicacy of their organs and recompenses them for some pleasures they cannot enjoy, and for some evils to which they are doomed." Jean Anthelme Brillat-Savarin

MetaFooder: linking you to food | @foodtwit

#97 Art

Art
  • participating member
  • 107 posts

Posted 30 July 2008 - 10:48 PM

My father used to regularly win bets from his colleagues at MIT by gargling liquid nitrogen.  I'm not sure what the trick was, but he never burned himself.  I'll have to ask him about it.

View Post


If you do not do it too long, you can gargle it or even hold it. I used to freak people out by sticking my hand in a dewar of LN2. Not only that I'd _leave_ it there until they were well past the freak out stage. It was pretty fun.

The trick is that since your hand is warm, the LN2 evaporates and creates a thin film of "air" that actually insulates your hand, mouth, or whatever. The problem comes in when your hand starts to cool down so the LN2 doesn't boil as much thus there is less thin film of gas protecting your hand. Also you have to be careful as it likes to freeze in collection points. Once I put my hand in a dewar as a fist and left it in for a very long time (like 30 seconds). My hand was mostly alright but I ended up with frostbite on the pads at the base of my fingers. There the gas couldn't form a nice protective layer for long enough. That was the end of my freak people out with LN2 days.

Of course, I still found other ways to have fun such as making Nitrogen Tetraiodide and tesla coils of various sizes...

Oh, small pieces of dry ice make for some nice belching too. Just be sure to drink something _first_. I wouldn't try that in a restaurant environment though. Some might think it a bit uncouth.

-Art
Amano Artisan Chocolate
http://www.amanochocolate.com/

#98 Art

Art
  • participating member
  • 107 posts

Posted 30 July 2008 - 10:50 PM

Is the price per L still under one dollar in the U.S.?

View Post


I have a 30 liter dewar and it costs me a bit more than $100 to fill it up. I need to buy a smaller one for smaller "projects"....

-Art
Amano Artisan Chocolate
http://www.amanochocolate.com/

#99 paulraphael

paulraphael
  • participating member
  • 3,007 posts

Posted 31 July 2008 - 07:27 AM

I've given up on my LN2 ambitions. Locally I found the price and inconvenience of getting the stuff to be discouraging (the price per liter isn't high, but all the suppliers I found had a minimum order).

If anyone's interested in my dewar (especially in the NYC area) give me a shout. Otherwise it's going back to the great ebay next week.

Edited by paulraphael, 31 July 2008 - 07:28 AM.


#100 Chocolot

Chocolot
  • participating member
  • 422 posts
  • Location:Ogden, Ut

Posted 31 July 2008 - 02:16 PM

I just talked with Art. He is out at the Bonneville Salt Flats sending rockets into space. I think he is a bit of a mad scientist!

Ruth Kendrick

Chocolot
Artisan Chocolates and Toffees
www.chocolot.com


#101 Art

Art
  • participating member
  • 107 posts

Posted 01 August 2008 - 10:17 AM

I just talked with Art.  He is out at the Bonneville Salt Flats sending rockets into space.  I think he is a bit of a mad scientist!

View Post


Yes, yesterday was spent out on the Bonneville Salt Flats launching rockets. (These are really big rockets -- not those little Estes toys that we all grew up with. Some weigh over 100lbs and fly up to 17,000 feet or so. You have to get FAA clearance in order to fly this high. About two or three miles away, was the "racetrack" which is just as flat as where we were. We could watch cars zoom back and forth at 200mph+

See these links to see some of the more impressive rockets that were launched yesterday:

http://uroc.org/inde...1481&Itemid=715
http://uroc.org/inde...=528&Itemid=715

Fun fun! Came home and spent the rest of the evening working on getting our new (well, built in the late 20's early 30's) melangeur going. There are some slight mechanical problems that have to be worked out before we can use it in production. It is a very beautiful machine though. In fact, it looks almost exactly like the melangeur in the "Avatar" engraving I use that shows on the left side of my posts.

-Art

Edited by Art, 01 August 2008 - 11:54 AM.

Amano Artisan Chocolate
http://www.amanochocolate.com/

#102 YPants

YPants
  • participating member
  • 66 posts

Posted 20 September 2008 - 04:13 PM

read a bit in On Food And Cooking today and it said something along the lines that when you freeze meat, ice crystals forms that kinda punctures the cellular walls and makes the liquid loss during cooking increase.

i know making ice cream with liquid nitrogen eliminates ice crystals, so does the same thing work with meat? would it be worth it at all?

#103 hongda

hongda
  • participating member
  • 112 posts

Posted 21 September 2008 - 08:27 AM

It's not that freezing via liquid nitrogen does not produce ice crystals, it's just that the ice crystals are smaller. The slower something freezes, the bigger the ice crystals, and analogously, the faster something freezes the smaller the ice crystals. I think it would depend on the choice of meat. If the piece of meat is large, the liquid nitrogen won't be effective in freezing it quickly.

#104 s0rce

s0rce
  • participating member
  • 33 posts
  • Location:Evanston, Il

Posted 21 September 2008 - 11:02 AM

as a side note it is possible to freeze water without forming crystals at all, this is often done by submerging very small samples into liquid ethane (freezes things substantially fast than liquid nitrogen). This vitrifies the sample, effectively maintaining the disordered liquid state but as a solid.
Professional Scientist (in training)
Amateur Cook

#105 YPants

YPants
  • participating member
  • 66 posts

Posted 21 September 2008 - 02:55 PM

It's not that freezing via liquid nitrogen does not produce ice crystals, it's just that the ice crystals are smaller.  The slower something freezes, the bigger the ice crystals, and analogously, the faster something freezes the smaller the ice crystals.  I think it would depend on the choice of meat.  If the piece of meat is large, the liquid nitrogen won't be effective in freezing it quickly.

View Post


yeah well nitpicking aside, i think it would be pretty sweet if u could actually freeze, say, salmon fillets or duck or whatever and actually have it thaw up nicely. kinda surprised there isn't more experimentation regarding this. i don't have access to liquid nitrogen sadly, was just curious.

#106 hongda

hongda
  • participating member
  • 112 posts

Posted 21 September 2008 - 04:23 PM

Well, that's how they do some individually quick frozen (IQF) items.

http://www.airproduc...QF_freezing.htm

On a small scale, rasberries and such can be IQF using dry ice.

#107 Tri2Cook

Tri2Cook
  • participating member
  • 3,683 posts
  • Location:Ontario, Canada

Posted 21 September 2008 - 05:01 PM

BLATANT UNSAFE INFORMATION WARNING: Do you have access to dry ice? If so, break up some into small chunks, put it in a container (not glass) and slowly pour some 190 Everclear in. Let it sit until it quits "boiling" (doesn't take long) and experiment away. This won't be as cold as LN2 (only about -100 f) and in some ways it's less safe (it won't roll off of your skin like LN2 so don't try the little dunking your fingers to move things around thing you see some people do with liquid nitrogen, use tools or cryo gloves and try not to let it drip on you when you remove things from the tank). It does make an effective and fun way to play with quick freezing things though. If you're going to freeze food items that are sealed in plastic and won't be in direct contact with the liquid you can use isopropyl alcohol instead of the Everclear (much cheaper).
It's kinda like wrestling a gorilla... you don't stop when you're tired, you stop when the gorilla is tired.

#108 StanSherman

StanSherman
  • participating member
  • 258 posts
  • Location:NE Iowa

Posted 14 July 2009 - 03:40 PM

http://www.telegraph...n-accident.html

The 24-year-old chef was experimenting with a recipe involving liquid nitrogen, which is used by chefs including Heston Blumenthal to freeze food, when there was suddenly an "enormous explosion", according to a report in the Berliner Morgenpost.

The young man, from Stahnsdorf, near Berlin, lost one hand in the explosion, which occurred at his girlfriend's mother's house.

He was rushed to hospital, where his other hand was amputated and his condition was described as life threatening and he remained on artificial respiration. <snip>

#109 Lisa Shock

Lisa Shock
  • society donor
  • 2,105 posts
  • Location:Phoenix, AZ

Posted 14 July 2009 - 05:08 PM

I know people who use liquid nitrogen as part of a medical/scientific company, and they have a lot of protocols for handling the nitrogen, canisters, and receptacles. (and they were making ice cream with it back in the 1960's) I get worried when I see people handling it in kitchen situations without safety gear, and using inappropriate containers for the nitrogen and the super-cooled resulting products.

Even really good restaurants occasionally do dumb things (I've seen the youtube videos) with it like dipping 100% metal spoons into a bowl of the liquid while the spoon is being held in a bare hand, or not wearing protective eyegear.

#110 mkayahara

mkayahara
  • participating member
  • 1,839 posts
  • Location:Guelph, Ontario

Posted 14 July 2009 - 07:26 PM

For those that are interested, there is a detailed article (in German) found here.

The money quote is this:

Vermutlich explodierte das Behältnis, weil der Druck darin durch die Erwärmung der Flüssigkeit massiv gestiegen war.

In other words, the liquid nitrogen caused the container it was in to explode, because of the pressure buildup. This is why it is important never to put liquid nitrogen into a sealed container! The German article is, in this and other respects, far from the fear-mongering nonsense that's been propagated in the English-language press.

The article notes that his left hand was ultimately saved, not amputated as previously reported. Also, it's probably important to note that he was working in a house, not a professional kitchen, at the time of the explosion.

Edited by mkayahara, 14 July 2009 - 07:27 PM.

Matthew Kayahara
Kayahara.ca
@mtkayahara

#111 Tri2Cook

Tri2Cook
  • participating member
  • 3,683 posts
  • Location:Ontario, Canada

Posted 14 July 2009 - 08:16 PM

Thanks mkayahara. I was interested in the additional information because the first article left me thinking WTF? It just didn't add up with the information they reported. The stuff doesn't just randomly suddenly explode for no reason at all. An inappropriate container is a whole different jar of gas though.
It's kinda like wrestling a gorilla... you don't stop when you're tired, you stop when the gorilla is tired.

#112 StanSherman

StanSherman
  • participating member
  • 258 posts
  • Location:NE Iowa

Posted 14 July 2009 - 08:29 PM

I seriously doubt any analysis by any news reporter regarding energetic materials. They usually only manage to get their own name correct.

This article came to me via a chemical engineer. There seems to already be a huge hole in the story including the good news that they saved one hand. Meanwhile everyone covers up what they did so we may never find out what actually went wrong. It's all in the name of safety.

#113 paulraphael

paulraphael
  • participating member
  • 3,007 posts

Posted 15 July 2009 - 08:31 AM

I can't speak for the article, but in general find that people who work with LNO2 don't respect its dangers as much as they should. This includes friends who are chefs, and friends who are molecular biologists!

Everyone I know is clever enough to prevent an explosion. What's worrisome is lack of eye protection (a small splash in the eyes is bad, bad news) and lack of respect for the problems associated with spills.

There are issues with big spills in enclosed spaces (suffocation). But a more likely problem is small spills that get inside your clothes. People get lulled into complacency by the cool way a blob of nitrogen just beads up and rolls off your hands. They don't stop to think about what happens if it falls inside your shoe and has nowhere to go. The result can be excised, frostbitten flesh, or amputated toes.

At a minimum, people should where lab goggles, roll up their sleeves, and kick off their shoes (or wear open shoes like flip flops).

#114 blais

blais
  • participating member
  • 19 posts

Posted 15 July 2009 - 08:51 AM

First off. Liquid nitrogen is dangerous. Frying oil is dangerous. Boiling water, pressure cookers, gas grills, fire, knives etc.

E-gullet can be dangerous as well obviously.

Please do not suggest to wear flip flops while working with liquid nitrogen. If you are supposed to wear gloves and goggles to be safe, then lets please suggest that people wear shoes and socks.

And, a drop of nitrogen in your shoe will not cause you to lose your toes or get frost bite.

But go pour some on your feet in flip flops and you could get burned.
Richard Blais

www.blaiscuisine.com

#115 paulraphael

paulraphael
  • participating member
  • 3,007 posts

Posted 15 July 2009 - 10:16 AM

Please do not suggest to wear flip flops while working with liquid nitrogen. If you are supposed to wear gloves and goggles to be safe, then lets please suggest that people wear shoes and socks.

And, a drop of nitrogen in your shoe will not cause you to lose your toes or get frost bite.

But go pour some on your feet in flip flops and you could get burned.

View Post


I strongly disagree. Regular shoes and socks are the least safe thing to wear with liquid nitrogen. You're right that a drop in your shoe won't cause frostbite, but a big splash most certainly will.

There are two safe approaches: protective gear (boots that won't let any liquid in, with an apron or cuffs covering the tops) or no gear at all. Spilling LN02 on bare feet won't hurt you ... it rolls off just as it rolls off your hands. Flip flops are the same.

If you're in a commercial kitchen, obviously bare feet and flip flops are not going to fly ... but working with it at home, that's exactly what I'd do.

#116 Chris Hennes

Chris Hennes

    Director of Operations

  • manager
  • 8,124 posts
  • Location:Norman, Oklahoma

Posted 15 July 2009 - 11:50 AM

You must be a lot less klutzy than I am! :biggrin: If the options are full protective gear or barefoot, I will absolutely choose protective gear. There are other dangers in even a home kitchen than the liquid nitrogen. Like, the heavy bowl full of that fresh ice cream that I just dropped on my foot. Doh!

Chris Hennes
Director of Operations
chennes@egullet.org


#117 blais

blais
  • participating member
  • 19 posts

Posted 15 July 2009 - 02:22 PM

you used the word amputated ? And you did say if it fell in your shoes you would get frost bite.

And what's the difference if your at home or in a professional kitchen ? If your cooking then you could spill oil, drop a knife, etc ? Both more dangerous.

And now you suggest to either wear boots, BTW, I've dealt with plenty of LN2 and never in 6 years under the most corporate of circumstance been asked to wear boots. Or, wear no protective gear.

wouldn't wearing partial protective gear be partially safer ?
Richard Blais

www.blaiscuisine.com

#118 troyml

troyml
  • participating member
  • 17 posts
  • Location:Minneapolis, MN

Posted 15 July 2009 - 03:13 PM

you used the word amputated ? And you did say if it fell in your shoes you would get frost bite.

And what's the difference if your at home or in a professional kitchen ? If your cooking then you could spill oil, drop a knife, etc ? Both more dangerous.

And now you suggest to either wear boots, BTW, I've dealt with plenty of LN2 and never in 6 years under the most corporate of circumstance been asked to wear boots. Or, wear no protective gear.

wouldn't wearing partial protective gear be partially safer ?

View Post



I've had very little actual experience with LN2, but I can see why street shoes would offer little to no protection from a LN2 spill. The liquid nitrogen rolls off when spilled on bare flesh because it rapidly forms a layer of nitrogen gas upon which it floats and provides an insulating effect. In a standard shoe the porous, absorbent nature of the materials shoes are made of would hold the LN2 in contact with the skin where it could cause frostbite. Bare feet, or flip-flops allow the nitrogen to escape, where it is not held in contact with the foot.

I am not saying don't wear shoes and socks in the kitchen. I had an interesting triangular burn on my foot for sometime because I dropped a slice of pizza that had freshly come out of the oven onto my bare foot in my home kitchen. It was an entertaining sight watching me run to the bathroom where I shoved my hot cheese coated foot under the bath spigot.

I'm pretty certain that what happened here was a pressurized vessel exploding. It says he stole the LN2 from his place of employment and I think it highly likely he did not have a Dewar with which to properly transport and store it. So if he put it into a regular vacuum thermos then the pressure would build without release until the thermos ruptured.

#119 C. sapidus

C. sapidus
  • participating member
  • 2,583 posts
  • Location:Maryland

Posted 15 July 2009 - 07:43 PM

From the Compressed Gas Association:

Heavy leather protective gloves, safety shoes, aprons, and eye protection must be worn to prevent possible contact with . . . the cold liquid or boil-off vapors which may result from spilled or splashed liquid.

Equipment and systems designed for the storage, transfer, and dispensing of cryogenic liquids . . . must be equipped with pressure relief devices to prevent excessive pressure buildup do to the vaporization of the cryogenic liquid as heat leaks into the system.



#120 paulraphael

paulraphael
  • participating member
  • 3,007 posts

Posted 16 July 2009 - 07:56 AM

And what's the difference if your at home or in a professional kitchen ? If your cooking then you could spill oil, drop a knife, etc ? Both more dangerous.


I don't know about your home kitchen, but mine is a controlled environment. I'm usually in it by myself, the pace is measured, and I won't get kicked out for failing to comly with the chef's (or OSHA's) rules. If I'm wearing flip flops, which I often do on hot summer days while cooking, I'm all the more careful when tossing food in a hot pan.


BTW, I've dealt with plenty of LN2 and never in 6 years under the most corporate of circumstance been asked to wear boots. Or, wear no protective gear.


Then you're working for people who don't observe even the most basic industry safety rules and recommendations.

wouldn't wearing partial protective gear be partially safer ?


Yes. But street shoes are not protective gear, partial or otherwise, with LN2. They're a hazard. Like wearing a neck tie around a printing press.

(Edited to add: in previous post I wrote "LNO2," which may or may not exist. I meant LN2)

Edited by paulraphael, 16 July 2009 - 08:01 AM.






Also tagged with one or more of these keywords: Modernist