jeudi, mars 09, 2006

liquid nitrogen ice cream

First, a disclaimer. I found this on 101cookbooks.com and haven't made it yet.

Having said that, the idea appeals to the science geek and the cook in me. Let me know if you're up for trying the experiment at my place. Or if you have a four foot tank of liquid nitrogen handy (or the ability to liberate one).

Liquid Nitrogen Ice Cream/Gelato Base
Serves 6.
heidi notes: This is a nice, creamy gelato-type base. Infuse it, add stuff, get creative. I wrote this recipe a few years back - I tend to use arrowroot instead of cornstarch as a thickener in recipes that need it (it is usually less-processed than cornstarch). But because I haven't tested arrowroot in this base, I'll give you the cornstarch version. If you use this as a base for liquid nitrogen ice cream, please read up on the safety precautions that must be observed when handling LN2.

4 cups whole organic milk
1 vanilla bean, split
1 cup sugar
3 tablespoons plus 2 teaspoons cornstarch
1 teaspoon vanilla extract

Place three cups of the milk in a saucepan with the vanilla bean over medium-low heat.

Meanwhile, pour the remaining 1 cup milk into a large glass measuring cup. Add the sugar and the cornstarch. Mix well.

When the milk starts to simmer, remove it from the heat and pour in the cornstarch mixture, stirring the whole time. Return the saucepan to medium-low and stir, stir, stir, until things start thickening up, 10 to 12 minutes. It should end up thicker than, say, a runny milkshake, but thinner than a frosty one.

Pour the mixture through a strainer into a mixing bowl, whisk in the vanilla extract, and let it cool on the counter for 20 minutes or so. I like to then chill it in the refrigerator for a few hours or overnight until it is completely chilled.

Now you are ready to place this mixture in a metal-bowl mixer and do the liquid nitrogen thing * or you can just freeze this using the manufacturer's instructions on a standard ice-cream maker.

* Liquid Nitrogen Ice Cream: play-by-play
To make liquid nitrogen ice cream you start with an ice cream base in a metal mixing bowl. Fire up the mixer (Kitchen-Aid was in use here) at low-med speed. Pour the liquid nitrogen into the bowl a bit at a time as the mixer is running. It freezes up ever so creamy and beautifully.

Will I die if I eat it? I asked that. I also asked a host of other questions. Are those plumes of Halloween-looking smoke coming off the bowl going to gobble up all the oxygen in the room? Are we all going to go to sleep and never wake up? You really, really, need to be careful with this stuff - do your homework and really get up to speed on the proper way to handle it. You need to treat it as seriously as you would a deep fryer filled with hot oil and the like. You like your fingers, right? LN2 can cause them to shatter. Imagine what it could go if you got it in your eyes.
Via 101cookbooks

2 commentaires:

Anonyme a dit…

i haven't done it this way yet but...

if you've got a vanilla bean, forget the extract. you won't need it.

i'd use cream for 1/4 to 1/2 of the liquid UNLESS you actually have liquid nitrogen or the old style ice and rock salt ice cream maker. and real cream - half and half does not work as well even if you get the same fat content overall. the individual fat globs are smaller. home ice cream makers with the frozen insert take a relatively long time to freeze and milk has too much water and not enough fat to fight the formation of large crystals - the death nell of creamy texture.

corn starch is my preferred way to thicken for home insert type machines, it works better than anything else i've tried. BUT you must boil it for it to work, none of this simmering for 10 minutes crap. just bring to a boil and then remove from heat, no need to
keep it rolling for several minutes. if you want to simmer things, then thicken with eggs or egg yolks. you'll get a richer texture too. eggs work great in a $10,000 machine, not so good with the frozen insert home variety.

definitely let the mixture sit overnight in the fridge. aging the mixture is key, especially if you
use eggs to thicken. at the very least the mixture should be just above freezing temperature before it goes into the machine. the less you have to bring the temperature down the less time it spends in the machine and the less time there is for large ice
crystals to ruin the party.

not that i have any strong opinions on how to make ice cream or anything ;)

scott :)

moriseylvr a dit…

My sister makes this all the time in her lab. She says it is decent.