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nathanm

Cooking with Liquid Nitrogen

218 posts in this topic

Do you mean Dewar?

I could I dont know how to spell it ..the big thing that you keep the liquid nitrogen in that has the dipper to get it out ..whatever that is called ..

It's actually the name of a person.

http://en.wikipedia.org/wiki/James_Dewar

oh thanks :smile:

I have nver had a problem finding or buying liquid nitrogen ...I have used it to freeze dry flowers ..I am sure fruit dust could be made very easily with a mortar and pestle and some nitrogen ..

my kids used to freeze grapes in it and drop them on the floor (with spoons not fingers of course ) so they would shatter into dust ...

just as I mentioned above check out welding gas companies you just need a safe container to take it home in (you can use a stainless steel thermos with out screwing the lid down ...just set it on top ...so the bottle does not explode ...

good luck


Edited by hummingbirdkiss (log)

why am I always at the bottom and why is everything so high? 

why must there be so little me and so much sky?

Piglet 

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I've recently started cooking with liquid nitrogen but so far have only used it for making sorbets and ice-creams. Funnily enough, I started doing this because I don't have an ice cream maker and liquid nitrogen is cheaper and faster for me (I made 3 different sorbets in under 30 min).

Making various powders using a mortar and pestle seems like a simple and very promising avenue, how long do the powders keep? Are they good for preserving aromatics (say a herb or lemon powder), or would something like this just end up tasting like dried powdered supermarket stuff?


Martin Mallet

<i>Poor but not starving student</i>

www.malletoyster.com

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Paco Rancero (from the Casino de Madrid) was doing some demos with this last year at the WGS in Singapore. He did up an "air" of olive oil, and then banged this into the LN. You took this in your mouth in one gulp, and the effect was a "Dragon Oil" with clouds of olive oil flavoured vapour blowing out of your nose.

Here's part of the post:

Dragon oil.

First he works up the air. “Foam and air are not the same”. This is an emulsion of a vinaigrette worked up with balsamic soy lecithin mixed with the oil to give a very foamy result.

I have got to get some liquid nitrogen for the kitchen. Paco and Fernando manhandle a big canister into the work zone, and then crack it open with a screw driver. Paco is grinning over the liquid nitrogen now, like an old friend has just shown up for a drink.

“At –196 C you should respect this. Don’t fear, but respect.” However, we next hear “normally when you work with nitrogen you must wear gloves. Me, no.”

And then it goes into a chilled metal bowl, tendrils of vapour creeping over the countertop like Morticia Adams’ skirt trails. It’s a fantastic table for a Halloween.

The “air” goes into the cloud, and comes out looking for all the world like a marshmellow. Our victim from the audience, cautioned to take it all in one go, can’t do it, and opens her mouth. Everything is vapour everywhere. The second volunteer does better, and the effect is one of a dragon blowing smoke down from its nose. The entire thing evaporates as soon as it hits the inside of your mouth, leaving a taste of olive oil, but exiting so quickly through your nose that you’re left amazed.

Cool. I gotta get me some nitrogen. I think the F1 fans in Bahrain might be able to help me out with this.

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I like the idea of the ice cream because it's fast, and requires no specialized machine (the expensive thermos and the protective gear are drawbacks).

One issue with ice cream is hardening it if you want it harder than the soft-serve consistency that the machine produces. When I made ice cream professionally, we had a -80 degree F flash freezer for hardening and curing the ice cream. It took 12 to hours in there, and then a few days in the regular freezer to come up to scooping temperature. The LN2 does it all in a blink.

The stand mixer looks like a natural way to do it.

How long will the LN2 stick around once you fill your thermos?

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I just use a styrofoam box with a lid (cut with vent holes), and the LN2 is usually good for about an afternoon if you don't disturb it. I only use about 1L at a time, and I imagine that a larger volume in a proper Dewar would last at least a day.


Martin Mallet

<i>Poor but not starving student</i>

www.malletoyster.com

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this time around our lab made liquid nitrogen sorbet for our Friday fun:

gallery_36048_4638_95168.jpg

I was surprised that I didn't have to use a sorbet recipe to achieve a non-icy product. We made raspberry lemonade sorbet (using just straight up juice from a bottle) and a guava puree one that was thinned down with orange juice before freezing.

The texture of these sorbets was amazing.

gallery_36048_4638_68953.jpg

Though we've done ice cream before, this set of experiments got me really excited. Maybe it was the Champagne we poured on top? :biggrin:

Next time we're making frozen margaritas!


flavor floozy

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I just use a styrofoam box with a lid (cut with vent holes), and the LN2 is usually good for about an afternoon if you don't disturb it. I only use about 1L at a time, and I imagine that a larger volume in a proper Dewar would last at least a day.

So can you actually go to a welding supply shop with a styrofoam box and say 'fill 'er up?'

This is safe?

And what exactly is a Dewar? Is there a reason you can't use a regular thermos (besides the possbilty of closing the lid all the way and turning it into a bomb)? What about a stainless thermos rigged so the lid won't shut all the way?

I'm also curious about measuring the correct volume of of the LN2. Is it difficult with all the steam and bubbling?

And what kinds of materials can you pour it into without worrying about thermal shock issues? I'm guessing a stainless steel measure would be ok; pyrex probably not ...

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I use LN2 for a variety of things since I have access through work (biotech lab).

One favorite is orange cell supremes. Place orange segments in LN2, place in a plasitc bag and hit with a rolling pin. his breaks up the orange into frozen cells.

Last night we mixed these with pastry rocks and cocoa nibs from lepicure, pastry rocks from chef rubber and granulized honey from an asian market. The resulting crunchy mix that crunched back was great.

Another use is similar to the "air" but we use popped popcorn. submerge popcorn for a short time in LN2, remove and serve.

Last fun item is to partially fill a balloon with liquid (I have use chocolate milk, fruit juices, etc), submerge balloon in LN2 until frozen, remove, pop balloon with torch and serve. Yields a hollow frozen sphere.

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As an observation from the photos we've seen here.....

Have you noticed how everyone working with liquid nitrogen always has a big grin on their face?

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I just use a styrofoam box with a lid (cut with vent holes), and the LN2 is usually good for about an afternoon if you don't disturb it. I only use about 1L at a time, and I imagine that a larger volume in a proper Dewar would last at least a day.

In a proper dewar, LN2 lasts a lot longer than a day. I have a 10 L dewar and if left untouched, it would take 45 days to evaporate (according to the manufacturer). I get a refill once a week, and I don't notice any loss at all.


Marc Lepine

Atelier Restaurant

Ottawa

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I have a concern in getting involved that might not be so obvious and that is oxygen depletion in my work area. do those who work with have a oximeter? How long approximately does 1 liter last when poured into a work container? What size room does 1 liter of ln2 become unsafe?


www.adrianvasquez.net

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Oxygen depletion is usually not an issue as long as the area is well ventilated. A 1L volume of liquid nitrogen expands to about 650L nitrogen gas, which is a little more than half of a cubic metre. Hope that gives a little perspective...there's not much danger from suffocation with the volumes you're talking about. As long as doors/windows are open and the air is moving around it's not a problem.


Kate

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Oxygen depletion is usually not an issue as long as the area is well ventilated.  A 1L volume of liquid nitrogen expands to about 650L nitrogen gas, which is a little more than half of a cubic metre.  Hope that gives a little perspective...there's not much danger from suffocation with the volumes you're talking about.  As long as doors/windows are open and the air is moving around it's not a problem.

thanks!


www.adrianvasquez.net

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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/ws/eBayISAPI.dll?ViewI...bayphotohosting


Edited by paulraphael (log)

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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.

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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/ws/eBayISAPI.dll?ViewI...bayphotohosting

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 (log)

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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.

2690929901_252d0102ab.jpg

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

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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.

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/

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

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/

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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 (log)

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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

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