Cooking with Liquid Nitrogen

[gfweb]

Has anyone in the bay ares been able to purchase liquid nitrogen with any success?  I've tried contacting Praxair near San Francisco but they did not allow me to purchase any LN2 from them.

If you don't need a big volume you might ask your dermatologist if she'd sell you some.

[William Colsher]

Do those of you who use LN2 also use the insulated bowl, gloves, etc?

[gfron1]

I do not.  I used to when I first started until I learned how it moved when poured into my bowl.

[Nowayout]

I buy mine from a local welding supply.  I buy it under a business name and they made me sign some hazmat document.

 

I found a used 50 liter dewar on ebay for around $100 (a real steal!).  It was some university surplus.  

 

I made a lid for it with a pressure relief valve as well as a valve and a draw tube for dispensing.  Works great!

Basically a poor mans version of this: http://static.coleparmer.com/large_images/0377367APP.jpg

 

Here is a pic of a similar one:  http://www.ebay.com/itm/LIQUID-NITROGEN-DEWAR-CRYOGENIC-TANK-679-/400765254972?pt=LH_DefaultDomain_0&hash=item5d4f787d3c

 

I don't fill it all that often, mostly for making LN2 ice cream, which is awesome!

[Lisa Shock]

I have been making LN2 ice cream since the early 1990s, and have things down to my satisfaction. But, I have an opportunity to do a demo in a location where I just don't feel like lugging my 7qt Kenwood out to. Would an immersion blender (all metal) work? -I know that I'll have to create an insulated base for the bowl and have all the usual safety gear, and take the usual precautions. I guess I am wondering if the blender will keep spinning at low temps?

[Kerry Beal]

I've got the feeling it won't - but only one way to know.

[Lisa Shock]

The venue won't mind a dry run. If it works, they get to eat ice cream. If it doesn't, they get to try to eat ice cream with metal shards, or a really hard slab of zero-overrun ice cream.

[Lisa Shock]

On 8/13/2014 at 6:58 AM, William Colsher said:

Do those of you who use LN2 also use the insulated bowl, gloves, etc?

 

I know this is an older post, but want to answer it for future readers. If it's been a while, I make a point to review the Liquid Nitrogen Primer by Dave Arnold.

 

I prep my room first, checking the ventilation. I make sure I have given a rundown of what will or might happen to anyone who isn't familiar with procedures -so that no one in an audience gets grabby, or decides to close the windows.

 

I dress for the occasion, plain slip-on chef shoes, cuffless long pants, long sleeve chef coat with sleeves unrolled over a t-shirt. I always wear goggles. (I get prescription ones from zenni.com) I wear gloves, I am after all, preparing food. I tend to prefer a sandwich of latex-free food handler gloves, silk glove liners (designed for outdoor sports), topped by another, larger set of food handler gloves. I got used to the layered gloves while pulling sugar. Just like any other time in the kitchen, hair is tied back and a hat is worn.

 

I also have long handled utensils that are seamlessly covered in silicon.

[dianapatil]

I did not find it easy to cook it with nitrogen as i was trying to make a big chocolate ball

[gfron1]

Lisa, I can't see how the immersion blender would work. The base blade doesn't create the surface area to finely aerate the ice. I know aerate isn't the right word, but its closest I can get. Going that route reminds me of a Pacojet with that ultrafine shave, but there's a tight fit between the PJ blade and the ice itself. So I think odds are against it working. When I've done it tableside (years ago), I've just used my largest/strongest balloon whisk.

[Lisa Shock]

Thanks! The whisk sounds like a better idea. When I use the mixer, I get about 5-10 revolutions and that's about it, so, I already know that it doesn't get whipped much - you don't have a lot of opportunity to add overrun. Anyway, the whisk is more theatrical and doesn't need to be plugged in, so, I will go with that with one of my removable silicon pot handles on it. (and, I learned to make the ice cream in the early 90s from a lab tech who had been making it since the 1960s) I am giving small portions to about a dozen people, so I plan on making 2 liters or so.

[Lisa Shock]

21 hours ago, dianapatil said:

I did not find it easy to cook it with nitrogen as i was trying to make a big chocolate ball

 

How big? And, what for?

[dianapatil]

Hi Lisa it was a medium sized bowl actually m planning to start up a cafe was practicing for the same some dishes,...

[Lisa Shock]

So, I went to the lab last night...

And I used a large industrial immersion blender and LN2 to make a test batch of frozen sugar water!

 

The blender, I am having trouble finding a picture online, sits on a steel cart, on wheels. (kind of like a large Hobart in size, but more boxy looking) It has a rectangular body, approximately 5 feet high. A hydraulic pump raises the blender shaft. The shaft is permanently affixed, and made of stainless steel. The tub they usually use to mix chemicals has a 50L capacity. We used a smaller Cambro tub from my house. I used sugar water to mimic a sorbet and give a few of the properties of ice cream.

 

I used a rectangular tub, which was not optimal. We made about 3 gallons of sugar water at 26°Bx and it was at room temperature, 72°. We started the mixture spinning and pouring in LN2 as it spun. 2 liters of LN2 gave us a watery slush consistency, so, we got more and continued. At that 2l LN2 mark, we noted that small icicles, each about 2cm long, were forming on the shaft. They fanned out horizontally. My lab partner speculated that they were pure water, but, I tested 2 of them and they were full strength sugar water. After adding more LN2, the icicles became much larger.

 

The corners got filled with frozen ice, while the center kept spinning. We got all the way to the center being like softserve, and stopped. The shaft had a coating sticking to it of about 1cm thickness. The ice in the corners was very soft with fine crystals, like a good sorbet. The machine had no problems. We did have some issues with splashing, as my cambro was relatively small. Next time, we will be using a larger container, preferably one which has a circular shape for more even freezing.

 

Not having a paddle wasn't such a big deal, as the cold was coming from the inside of the tub. In traditional ice cream makers, the cold comes from outside the tub.

 

I am waiting for a big sale on milk, and I am about to purchase the 22qt round Cambro tub. More test results as they happen.

[KennethT]

I haven't made ice cream with LN, but I have done small quantities with dry ice (the ice cream comes out carbonated, which is what I wanted), and I made the small quantities with a hand mixer.  But I was thinking, for larger quantities, you might be able to get good results from an industrial paint mixer - which is sort of like 2 helixes (helixi?) on a stick that you attach to an electric drill.  We use it industrially to mix several gallons of thick epoxy, so I'd imagine it would work well for ice cream as well.

[Sparren]

I visited The Fat Duck a couple of weeks ago and would like to try the liquid nitrogen poached meringue at home.
Is there any risk that not evaporated liquid nitrogen could be captured inside the meringue causing damage?

Is a glass jar suitable for containing the LN in while poaching?
I have recipe for the green tea and lime but if anyone has recipe for the new ones (pina colada, vodka lima, campari soda, paloma) that are on the menu now I would appreciate it

 

Edited August 12, 2016 by Sparren
Added picture (log)

[Lisa Shock]

I doubt that liquid LN2 would get trapped inside: it really wants to change into a gas.

 

I would not trust a glass container unless it is certified for use with LN2 (lab equipment) -too much can go wrong. In the US, in general, the health department does not permit food preparation in glass containers. If you break one, the whole room has to be scrubbed down and mopped, plus any open containers of food (stockpots, fat in the fryolator, water in the pasta boiler, that tray of garnishes, etc.) must be discarded.

[Sparren]

Thanks, I did a test run today and it worked very well. Vodka/lime this time.