Behold the smooth, sweet powers of liquid N (Liquid nitrogen ice cream! Yum!)

Popular Science ^ | July 2003 | Theodore Gray

[mhking]

Liquid nitrogen is cold. Very cold. So cold that if a drop falls on your hand, it feels like fire. So cold that it can turn a fresh flower into a thousand shards of broken glass. So cold that it can make half a gallon of ice cream in 30 seconds flat.

I first heard about liquid nitrogen ice cream from my friend Tryggvi, an Icelandic chemist working in the Midwest (these things happen). He suggested we make it for dessert at a dinner party I was planning. Yes, he said, he had a recipe, something he'd seen in Chemical and Engineering News.

Now, right off the bat you have to worry about a recipe found in Chemical and Engineering News, the principal trade publication for the sort of people who build oil refineries, shampoo factories and large-scale plants for the fractional distillation of liquefied air (which is where liquid nitrogen comes from). But for the party I was planning, it was perfect: The well-known author Oliver Sacks was coming to visit with my collection of chemical elements; I needed some after-dinner entertainment.

My first concern was whether we would survive the ice cream. That and, if it didn't kill the cook, whether it would be any good. I had visions of hard, crusty stuff that caused frostbite of the throat. It turned out nothing could be further from the truth.

We mixed up a standard ice cream recipe calling for two quarts of cream, sugar, eggs, vanilla and flavoring. (Just about any ice cream recipe and flavor will work.) Then, working in a well-ventilated area (lest the nitrogen displace oxygen from the air) and with due regard for the ability of liquid nitrogen to freeze body parts solid, we gently folded about two liters of nitrogen syrup directly into the cream, much as you would fold in egg whites.

The result, literally 30 seconds later, was a half-gallon of the best ice cream I'd ever tasted. The secret is in the rapid freezing. When cream is frozen by liquid nitrogen at –196°C, the ice crystals that give bad ice cream its grainy texture have no chance to form. Instead you get microcrystalline ice cream that is supremely smooth, creamy and light in texture. Martha Stewart, eat your heart out.

The kids were amused by the clouds of water vapor, though being kids they didn't find anything out of the ordinary in the procedure. They probably think everyone makes ice cream this way. Boy, will they be in for a shock the first time they see it done the old-fashioned way at camp: You want me to do what for a half hour?

A word of caution: Liquid nitrogen can be dangerous in careless hands. Tryggvi and I are both trained chemists, and he actually knows what he's doing. Don't try anything like this unless you do too.

[mhking]

LIKE ICE CREAM FROM TRITON [1] Besides the liquid nitrogen, no special ingredients were used in this experiment. [2] The non-cryogenic ingredients were combined in a mixing bowl. [3] The nitrogen was added a cup at a time. Note the use of heavy cryo gloves—this was not an occasion for oven mitts. [4] The concoction was stirred thoroughly and continuously to keep an unbreakable crust from forming. [5] The ice cream was ready to eat when smooth and free of lumps.

(Bottom right)Theodore Gray is a co-founder of Wolfram Research, Inc., maker of the software program Mathematica. In his spare time he plays with elements at periodictabletable.com.

Photographs by Jeff Sciortino. Styling by Kelly McKaig.

[mhking]

"Hold muh beer 'n watch this!" PING....

If you want on or off this list, please let me know!

[null and void]

A little dab'll Dewar...

[Sokol]

cool...

[Drew68]

Great post! Thanks!

[not_apathetic_anymore]

VERY cool. I'm just geeky enough to want to try this!

[Drango]

Note to self: Do not try when drunk.

[wafflehouse]

cool!

[Ruth A.]

They did a demo of this as a shop that deals in propane and other gases, etc. They used cream, milk and jam. It was so good. Plus, the temperature dropped in the area they were making it.

[supercat]

I wonder if these guys use lox as a barbecue starter?

[HiTech RedNeck]

Only if they want to vaporize the grill.

[Reeses]

To make an excellent low carb ice cream replace the sugar with a Davinci sugar-free syrup. It's sweetened with Splenda which freezes like regular sugar. I recommend. It makes a professional quality ice cream.

[drlevy88]

Pedantic point: it isn't N, it's N2.

I wonder how well pulverized dry ice would work. Not as cold as liquid nitrogen, but much easier to get. Pulverize it in a blender or food processor. (With very, very good ventilation such as a large fan blowing full blast from a window into the kitchen.)

[ffusco]

How about steaks cooked with sodium?

[Billy_bob_bob]

That's the best part. Wait for everything to cool off, then take the remains back to the store and demand a refund. I recommend using the cheapest portable grill or hibachi available. The expressions on the faces of every person working at the store will be worth the price of the LOX.

[RightOnTheLeftCoast]

Smoked salmon is a lousy barbecue starter.

[Paleo Conservative]

The result, literally 30 seconds later, was a half-gallon of the best ice cream I'd ever tasted. The secret is in the rapid freezing. When cream is frozen by liquid nitrogen at –196°C, the ice crystals that give bad ice cream its grainy texture have no chance to form. Instead you get microcrystalline ice cream that is supremely smooth, creamy and light in texture. Martha Stewart, eat your heart out.

But how much does it cost to make ice cream this way?

[supercat]

Only if they want to vaporize the grill.

So don't use a grill--use a pit. BTW, have you seen the photos of the lox barbecue? Pretty darned impressive.

[coloradan]

-196 C is about -320 F, in case anyone is interested.

[drlevy88]

Based on what I googled up with "liquid nitrogen" "price" "liter" this recipe might use $9 worth of the stuff if bought in that small quantity at retail. Not counting the dewar flask (dunno if Thermos bottles would be good enough).