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Making Ice Cream With Liquid Nitrogen
JasonMaggini writes "Popular Science has an article on how to whip up a batch of ice cream in 30 seconds or so by using liquid nitrogen. Just the thing for those hot summer days. The article is by Theodore Gray, creator of the ultra-spiffy Periodic Table Table."
That's how the ice cream at the dippin dots stands is made. They just put drops of the unfrozen mixture into liquid nitrogen.
This is the exact process that Dippin' Dotsuses to make ice cream in little tiny spheres (about 2-5 mm across).
The process was determined around 1988 by Curt Jones (a biologist interested in cryogenics...the science of freezing...not cryonics, the science of "Disney on Ice"). He started his company and now you can get Dippin' Dots everywhere from malls to theme parks.
You might even be able to catch a rerun of the FoodTV show, Unwrapped, where they discuss the manufacturing process. It's show #CWSP11 and it'll air again at these times.
PS - Yes, I know Walt Disney isn't actually frozen....but Teddy Ballgame is.
Mordor...a magical, mythical land where women are more rare than dragons--but where every man would rather find a dragon
1001 things to do with liquid nitrogen.
People made tea from tea essense.
What people did do is to put a lump of sugar into their mouth as they were drinking the tea -- instead of putting it into the tea.
This was more of a matter of personal preference than desire to save sugar (although there was a little bit of both -- sugar was often given out via ration cards)
This page clearly shows they're already doing this in an industrial setting. Also, there's something called "sonication" that uses sound to make small particles of ice cream intermediate & pre-products of a powder-like consistency. And those ice-cream "dots" that are sold at malls are just ice cream mixture drops frozen in LN2.
The biggest trick the devil pulled was letting lawyers become politicians so they can write the laws.
at Liquid Nitrogen Ice Cream.
Technology to do this was invented by Iowa State University a few years back, as referenced here: http://www.nitroicecream.com/company%20history.htm .. nothing new.... i must say, damn good ice cream
One man told such a story to the Darwin Awards folks....
Gimme a break. Science camps all over the continent have been doing this for years. It's easy:
1. Get cream
2. Add liquid nitrogen, which freezes the cream then evaporates
3. You've got ice cream.
It's called the subjunctive. See also, "be that as it may ..."
reverseengineer wrote: The Leidenfrost effect is also sometimes demonstrated by wetting your hand with water, and then briefly plunging your hand into a container of molten lead. The same principle applies, as the lead is above the Leidenfrost point of water, so the water will form a vapor layer around your hand that insulates it from the molten lead.
If memory serves, Richard Feynman did this as a kid.
Then, when he was older (early twenties, say), he was telling some friends of his about it, but they didn't believe a word of it.
So there was nothing for it but to get some molten lead and give a demonstration.
Unfortunately, what he failed to realise was that, in the intervening years he had passed through puberty and grown a lot more hairs on the back of his hands. The hairs acted like wicks, and so it hurt like hell.
(of course, afterwards, his hands were quite bald again)
(at least, that's the way I remember the story.. It's probably in Surely You're Joking, Mr Feynman!. Even if it's not, I highly recommend reading that book anyway. It's a great (nontechnical) read).
Repton.
They say that only an experienced wizard can do the tengu shuffle.
at /etc (fun with liquid hydrogen) in Realplayer format. The same guys that host the Geeks In Space shows.
If you outlaw the law, only criminals will have laws
I'm surprised by two things by this: One is that he even managed to swallow, I haven't really tried, but my experience is that it boils extremely fast, and I would think it would be very hard to do that.
The other surprising thing is that he wasn't more seriously injured, or indeed that he lived to tell about it...
BTW Nobel Prize winner Douglas Osheroff told me he actually lets that stuff go far down his throat.
Employee of Inrupt, Project Release Manager and Community Manager for Solid
Here's a quick rundown of liquid nitrogen safety points. Get some liquid nitrogen, have fun; we've been making ice cream and much more for years. Just read this first and be safe.
http://www.isber.org/pdfs/karpinski.pdf
http://www.nitroicecream.com/
They exhibited at the IAAPA Convention last November. The stuff was excellent - very smooth.
The machine used a large tank of liquid nitrogen, and basically worked by spurting ice cream mixture into a bucket, then spraying it with the nitro. Repeat the process 100 times or so, and you've got 5 gallons of the stuff.
The specific trick to which you allude involves dipping your hand in water and then quickly in benzene. The two liquids are pretty much insoluble in one another, so a (somewhat spotty) layer of water remains between your hand and the benzene layer. If you ignite the benzene, most of it doesn't burn in contact with the skin, and the water with its high specific heat soaks up most of the heat of combustion, so it doesn't hurt--in principle.
Feynman discovered that as an adult, the hairs on his hands would wick the benzene down into direct contact with his skin...and hurt like hell.
The high specific and latent heats of water permit a number of amusing tricks. For example, you can boil water over an open flame in a paper cup. The boiling water absorbs heat from the paper cup, keeping it at a warm (but nowhere near combusting) 100 C.
You can also mix roughly equal parts water and isopropyl alcohol to obtain a solution that will burn, but doesn't damage most inanimate materials. Again, the big latent heat of vaporization of water soaks up almost all of the heat generated by the combustion of the alcohol. You can soak a large-denomination bill in this stuff and 'burn' it. Hint: test the solution on something disposable, first. ;)
~Idarubicin
The more correct short answer is that you easily can.
LN2 is not a controlled substance. In most any area, it's simply a matter of opening up the phone book and finding a gas supplier. Many welding gas and medical gas companies provide it, and most sell to the public, and those that don't usually don't because they are set up to deal with businesses through purchase orders.
I only know the suppliers for the places I've lived---Praxair in St Paul, MN, and Merriam Graves in western NH, but both will happily sell you bulk dry ice, LN2, various gases in bottles, etc. I've done it at both places. Just be prepared to leave a *large* deposit on the LN2 dewar. If they ask too many questions tell 'em you're an artist (artists, especially those that weld, buy the freakiest damn things at times). And the LN2 ain't cheap, either. Depending on the supplier be prepared for between $80 and $200/dewar. (Although I guess if you compare it it's probably cheaper per volume than beer...)
Then again, due to the massive number of LN2 dewars I use at work, I'm on a first name basis with Merriam Graves' delivery guy...
But to go back to the comments of the guy I'm responding to...don't mess around with this stuff without thinking about it. It's real easy to burn yourself (wear eye shields), it easily splatters since it boils upon contacting most anything, etc.
Where I get liquid nitrogen is from a local welding supply shop. I just take a 1 liter metal thermos with a hole drilled in the lid and they are happy to fill it for my for about $25 dollars. Call around a little bit and I'm sure there is a place in your area.
OK, I'll bite. I'm posting anonymously for a reason...
I happen to be one of the very few people in this world dumb enough to have consumed liquid nitrogen. Not on purpose, mind you...well, sort of not on purpose.
OK, so I love liquid nitrogen. I play with it all the time. It's fun stuff, trust me. And on occasion I put small amounts in a drink to both cool it down and for the cool smoky effect. It's fun.
Now on one occasion I did this but did not wait until the liquid nitrogen had completely evaporated before I took a drink. I noticed this immediately. According to a friend of mine who was there at the time, my eyes opened wide with horror and if ever there was a facial expression for "oh shit" I had it.
I immediately threw back my head and belched like I've never belched before (or since). It was quite the experience. After it finally ended I gasped for air and kind of recovered. I felt kind of strange for the rest of the day, but in the end I was OK and didn't have to get medical attention.
Now I don't know exactly how much liquid nitrogen I consumed, but it couldn't have been very much. I can easily imagine a larger dose being fatal...so I would advise anyone out there reading this to avoid consuming liquid nitrogen in the future. Trust me.
A very stupid AC.
Developed this one myself - it's quicker and easier than ice cream and it's very good.
2 cups low-pulp orange juice
1 cup sugar
Mix sugar and orange juice. In a large wooden or plastic bowl (metal sticks too much), slowly stir in liquid nitrogen until the desired consistency is reached.
I'd also recomment using a wooden spoon. I used a hand mixer once, and due to the low viscosity of liquid nitrogen, it spewed droplets everywhere.
One of these days I want to try making deep-fried liquid nitrogen ice cream. My goal is to get an 800 degree F temperature span in the making of the stuff.
Remember, be careful with the LN2. It's easy to over-freeze stuff. I once got my tongue stuck to a frozen banana, and it was rather painful.
Scientific American published an article on this very topic ten, maybe twelve years ago. 'Twas in the Amateur Scientist column in an issue that focussed on food science. The authors describe a recipe for making ice cream for a crowd in minutes using liquid nitrogen. If I remember correctly, they recommended using equal parts ice cream base (custard) and LN2.
Also presented in the same article is a really nifty recipe for "Frozen Florida," which as the name suggests, is sort of the opposite of Baked Alaska.
Sorry, I can't put my finger on the exact issue, but I'm sure someone out there has a collection that goes back that far and can help us out.