"Fast" Ice Cream With Dry Ice

[KennethT]

Lately, I've been thinking a lot about making ice cream with liquid nitrogen... A) because it sounds really cool and B)I love high quality home-made ice cream but don't have an ice cream machine (or the space for one!).... I think we've all seen the demo where you take your ice cream base, pour in some LN, stir like crazy and in 15 seconds... POOF! Ice cream! With a really fine texture, no less...

My biggest problem is sourcing the LN... and also, I don't have a Dewer (sp?) flask to store it in, if I can procure the LN....

Another idea hit me today as I was reading a different topic on the EG... what if you took a bunch of dry ice pellets (much more readily available than LN) and added to rubbing alcohol (freezing point lower than the dry ice) and put that in some kind of container... then the ice cream base (in it's own metal container) is put in the container with the cold alcohol, instantly freezing the sides of the container.... if this is done while stirring like crazy - I'm thinking of an industrial paint stirring rod attached to a drill - it works great for paint! and available at sears... I would think that it could reproduce the same effect as a churning ice cream maker, but a lot faster, and with smaller grain size because of the quicker freezing...

Can anyone think of anything I'm not thinking of as to why this might be a bad idea?

Edit to correct bad typos....

Edited September 23, 2008 by KennethT (log)

[YPants]

why get an industrial strength paint stirrer and a drill instead of just getting a LN container?

also, the container would work as an insulator so the -70 C your solution presents might not be cold enough to prevent ice crystalisation.

[Tri2Cook]

Crush the dry ice really fine and mix it right into the ice cream base in a stand mixer. Heston Blumenthal did it in one of his "Perfection" episodes. Just make sure the dry ice is well crushed, you don't want to be chewing on or swallowing a chunk of the stuff... unless frostbite of the esophagus or mouth sounds fun. But to answer your question, the cold alcohol bath should work. Assuming you keep the bath cold enough. One of my ice cream machines (I bought it from eG member Kerry Beal) uses an alcohol bath between the unit and the container. It uses a compressor instead of dry ice but the principle is the same. One thing about the stirring rod, it won't function as a scraper so you'll probably get a thick layer of really hard frozen ice cream around the sides.

[KennethT]

Crush the dry ice really fine and mix it right into the ice cream base in a stand mixer. Heston Blumenthal did it in one of his "Perfection" episodes. Just make sure the dry ice is well crushed, you don't want to be chewing on or swallowing a chunk of the stuff... unless frostbite of the esophagus or mouth sounds fun. But to answer your question, the cold alcohol bath should work. Assuming you keep the bath cold enough. One of my ice cream machines (I bought it from eG member Kerry Beal) uses an alcohol bath between the unit and the container. It uses a compressor instead of dry ice but the principle is the same. One thing about the stirring rod, it won't function as a scraper so you'll probably get a thick layer of really hard frozen ice cream around the sides.

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I thought about adding the dry ice directly to the base, but I didn't know the "purity" and food grade-ness of it... I wonder if there would be trace amounts of who knows what in there that I don't know if I'd want to eat...

It also occured to me that the sides of the canister would freeze much quicker than the middle - and would probably need to be scraped every once in a while in between stirrings... or I figured I might be able to scrape the sides with the stirrer as it's stirring... I guess it's something I'd have to try in order to see how it goes...

[TheSwede]

...

It also occured to me that the sides of the canister would freeze much quicker than the middle - and would probably need to be scraped every once in a while in between stirrings...  or I figured I might be able to scrape the sides with the stirrer as it's stirring... I guess it's something I'd have to try in order to see how it goes...

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The freezing will only be at the sides, so you will have to constantly scrape the walls of the container. That is pretty much how an ice cream machine works.

Why not just get an cheap ice cream machine? The variety where you put the bowl in the freezer can't be that expensive and does the same you want to do.

[KennethT]

...

It also occured to me that the sides of the canister would freeze much quicker than the middle - and would probably need to be scraped every once in a while in between stirrings...  or I figured I might be able to scrape the sides with the stirrer as it's stirring... I guess it's something I'd have to try in order to see how it goes...

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The freezing will only be at the sides, so you will have to constantly scrape the walls of the container. That is pretty much how an ice cream machine works.

Why not just get an cheap ice cream machine? The variety where you put the bowl in the freezer can't be that expensive and does the same you want to do.

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yeah, I know ice cream machines aren't very expensive - probably between $50-$100 here... but I wouldn't use it very often, and I have very little space - both countertop and cupboard space... (it's a tiny nyc apartment kitchen)... so, I'm tyring to find a way around this for the "once-in-a-blue-moon" that I actually decide to make ice cream... I already have a drill, and the paint stirrer is cheap and easily obtainable (and takes up almost no space)...

Plus, this seems a lot more fun than sticking the base in the machine!!!

I think, since the materials are so cheap, I may just try it one of these weekends when I have some time... I"ll try to take pictures to document my failure, I mean hopeful success!!! haha.... hopefully there won't be any pics in there of me in the emergency room dealing with cryogenic skin burns!!!

[dougal]

...

It also occured to me that the sides of the canister would freeze much quicker than the middle - and would probably need to be scraped every once in a while in between stirrings...  ...

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Ice cream makers don't actually stir the mix so much as continually scrape the base and sides - the gap between bowl and "dasher" is critically small - and important I believe in controlling the final texture. The other function of the dasher is to incorporate air into the freezing mix. "Overrun."

My Gaggia machine's dasher rotates at maybe 10 rpm. Can your drill really go that slow?

Incidentally, if one uses the Gaggia as a bowl-within-a-bowl, alcohol is used between the bowls as a non-freezing, conformal (liquid!) thermal link between the inner bowl and the freezer coils.

If you already have a chest freezer and a stand mixer (like a KitchenAid), then the simplest thing would be to get the mixer "ice cream maker attachment". This is a bowl that gets frozen and an appropriate paddle acting as a dasher.

If you store the bowl in your freezer, you can pack flexible bags of stuff like peas inside and around it - so the amount of wasted space it takes is minimal, and its always chilled ready to use.

But if your freezer has built-in shelves, check very carefully that there is enough shelf-to-shelf height to take the freezeable bowl.

Edited September 24, 2008 by dougal (log)

[KennethT]

...

It also occured to me that the sides of the canister would freeze much quicker than the middle - and would probably need to be scraped every once in a while in between stirrings...  ...

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Ice cream makers don't actually stir the mix so much as continually scrape the base and sides - the gap between bowl and "dasher" is critically small - and important I believe in controlling the final texture. The other function of the dasher is to incorporate air into the freezing mix. "Overrun."

My Gaggia machine's dasher rotates at maybe 10 rpm. Can your drill really go that slow?

Incidentally, if one uses the Gaggia as a bowl-within-a-bowl, alcohol is used between the bowls as a non-freezing, conformal (liquid!) thermal link between the inner bowl and the freezer coils.

If you already have a chest freezer and a stand mixer (like a KitchenAid), then the simplest thing would be to get the mixer "ice cream maker attachment". This is a bowl that gets frozen and an appropriate paddle acting as a dasher.

If you store the bowl in your freezer, you can pack flexible bags of stuff like peas inside and around it - so the amount of wasted space it takes is minimal, and its always chilled ready to use.

But if your freezer has built-in shelves, check very carefully that there is enough shelf-to-shelf height to take the freezeable bowl.

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I've used an inexpensive ice cream maker before - years ago - and the rotation of the bowl serves to scrape the sides of the canister and continually mix the contents of the bowl - if I remember correctly, the dasher was angled so that the frozen cream that sticks to the wall is scraped and shoveled into the center of the bowl... but the difference is that the canister is only at maybe -10degF (the absolute coldest my freezer will get, not including averaging the temp. for the defrost cycle, door opening, etc.) So, the ice cream doesn't freeze that quickly up against the wall because it's not THAT cold, so you can scrape it slowly which will incorporate air, and continually expose surface area to non-frozen cream.

The stand mixer is a great idea - unfortunately, I don't have a stand mixer (wish I did though), let alone the space that one requires!!!

The dry ice sublimates at -109degF (or something around there) - so even if I dump a bunch of it into a bowl of alcohol - maybe the alcohol (after the bubbling stops) will be around -75degF??? I'll check with a thermocouple when I get to try it... anyway, I'd imagine it'll be a LOT colder than what my freezer can do.... I figured I'd need to stir really fast in order to keep things more uniform in the quick freeze (and incorporate air and not have a solid frozen chunk)... plus, I figured that as the drill spins, I could drag it up and down the sides of the canister (effectively scraping the side of the canister) every few seconds which will continually re-introduce the warmer cream...

[paulraphael]

The only thing I'd be concerned with if you're using the dry ice in the manner of an ice/rock salt machine is that the frozen ice cream could build up on the sides so fast and so hard that it would defeat any attempts to scrape it off ... either stall your machine or stall your arms.

That's where the elegance of blumenthal's methods come to play.

Maybe you could do some research on the purity of dry ice from the supermarket. My guess is that it's considered food grade.

I gave up on LN2. Too big a hassle if you're not working at a lab or restaurant that stocks the stuff in bulk. Expensive, too. Every supplier had a minimum order. And you need quite a bit of it. I reaized it would double or tripple the cost of my ice cream. And then there's the hassle of driving to go get the stuff. And the money I already spent on a tank (been too lazy to photograph it for ebay!)

[EllenC]

Martha Stewart had Blumenthal on her show last week. Here is a link to his recipe for ice cream using dry ice. Click

[syoung68]

I just watched Alex and Aki make ice cream with dry ice in a stand mixer on Monday. It was delicious. They used pretty big chunks of ice as opposed to finely crushed so they could see any remaining ice and avoid it.

KennethT: I understand that you do not have a stand mixer, it might be time to invest.

Coincidently, the guys over at Hungry in Hogtown just did some icre cream comparison taste tests including LN2 made. The interesting thing was that the Kitchen Aide attachment not only came in second to LN2, but some tasters liked it better.

You can check it out here: http://www.hungryinhogtown.com/hungry_in_h...d-nitrogen.html

[KennethT]

I like the idea of Blumenthal's method - and Alex and Aki's method with the dry ice...

None of the supermarkets in my area carry dry ice - but there are a few ice places that have it... I'll have to inquire to see if it's food grade... if it is, then it makes the task a lot easier...

I can imagine that as soon as I stick my ice cream container in the container of alcohol/dry ice, the ice cream against the wall freezes instantly and all of a sudden I've got an ice cream rock...

Putting chunks of dry ice into the mixer solves that problem... plus, the paint stirrer at high speed, I definitely think it'll have no problems...

FOOD GRADE DRY ICE, WHERE ARE YOUUUUUUUUUU??????!!!!!!

[paulraphael]

Coincidently, the guys over at Hungry in Hogtown just did some icre cream comparison taste tests including LN2 made. The interesting thing was that the Kitchen Aide attachment not only came in second to LN2, but some tasters liked it better.

Yeah, the KA attachment does a really good job, especially if you can turn the temp down really low in your freezer when chilling the bowl. My freezer is gets the thing between -6F and -10F. I've been able to freeze a pint of ice cream in as little as 4 minutes and a quart in as little as 12 minutes. The result is a very smooth texture.

LN2 is obviously going to be faster and smoother. But the real test, I think, is the texture after the ice cream hardens in the freezer. Ice cream continues to metamorphose indefinitely ... small ice crystals merging with larger ones, etc.. So past a certain point of initial smoothness, I suspect the stability of your mix and the stability of your freezer make a bigger difference than the freezing method.

[aliaseater]

I've had good results using an immersion blender, with the ice cream in a bowl. Simply churn every fifteen or twenty minutes until the mix becomes too firm to go any further.

[KennethT]

I've had good results using an immersion blender, with the ice cream in a bowl. Simply churn every fifteen or twenty minutes until the mix becomes too firm to go any further.

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Interesting - I wondered how an immersion blender would work... I'm a little confused on your method... When you put the liquid base in the bowl, you then add teh dry ice to the bowl and use the stick blender?

[KennethT]

Martha Stewart had Blumenthal on her show last week.  Here is a link to his recipe for ice cream using dry ice.  Click

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I just checked out the video clip of Blumenthal doing this... thanks for the link!!!

A few times he refers to the idea that you can do this at home very easily, and he never says "just make sure to get food-grade dry ice" or anything like that...

I wonder if there is such a thing as food grade dry ice...

Maybe I'll just try some, and hopefully I won't go blind...

[Pam R]

I'd look for the food-grade stuff - see if there is such a thing available. The few times I've purchased dry ice for packing food for shipment, it hasn't been . . clean would be the best word.

[ermintrude]

Did this in a thermomix. Added the dry ice, blitzed in thermomix poured in ice cream mixture.

But some problems along the way, the dry ice was hard to crush so some big chunks, also I used to much dry ice, so the ice cream was fizzy when I tried to reblend in the thermomix as it made the bowl go very very cold this caused it to error (Only way the error resolved was when the bowl came back to normal temp - talking to a thermomix representative they think this could be due to ice formation on the contacts which would happen the moment I lifted the bowl out.

However leaving the ice cream to sit so the excess CO2 evaporated the ice cream was great - and considering I was using milk not cream I was impressed.

Also be careful and wear gloves when dealing with dry ice, if you spill some liquid nitrogen on your hand it will evaporate and form a barrier and the nitrogen gas will protect your hand and liquid is easy to displace. If you drop a chunk of dry ice on your hand while the same effect can occur if the weight of the dry ice overcomes the pressure of the CO2 it will burn you. This is why, I assume, if you watch perfection Heston Blumenthal's does not use gloves with liquid nitrogen but does with the dry ice. Best of all use appropriate gloves when using either.

[KennethT]

I'd look for the food-grade stuff - see if there is such a thing available.  The few times I've purchased dry ice for packing food for shipment, it hasn't been . . clean would be the best word.

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I agree... food grade is the way to go - but I have no idea where to get it... a quick google search found 3 companies in Manhattan that sell dry ice... one of them never heard of food grade dry ice and had no idea if his stuff was or wasn't (I've actually bought some from him a few years ago for an industrial purpose - and it looked pretty clean)... another said "why would you want it food grade - you can't eat it!" I haven't called the last one yet....

Any ideas where to get it in the NYC area?? Preferably in Manhattan?

Thanks!

[flacoman]

Tried it last night : Think I used too much dry ice ; the finished product ended up carbonated!

Perhaps if I cooled the base more first ... or made some nice bubbly sorbet.

Advise please

Jorge

[KennethT]

Tried it last night : Think I used too much dry ice ; the finished product ended up carbonated!

Perhaps if I cooled the base more first ... or made some nice bubbly sorbet.

Advise please

Jorge

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Check out the Martha Stewart video with Heston Blumenthal linked above in a previous post... he did it with the dry ice, but it didn't seem like he carbonated the ice cream - Martha and some other guy (maybe the producer?) both said it was really smooth textured, but no once commented on a fizzy feeling... it didn't seem like he added that much - and he didn't add it all at once either - he started the mixer then added a spoonful, the another spoonful, then another until he thought it looked right...

Another thing Blumenthal mentions in the recipe attached to the video is that the base should be chilled in the refrigerator before freezing with the dry ice... maybe that would keep it from getting to fizzy???

I'm going to try to do a test this weekend - will post how it goes...

Edited September 26, 2008 by KennethT (log)

[Chocolot]

Tried it last night : Think I used too much dry ice ; the finished product ended up carbonated!

Perhaps if I cooled the base more first ... or made some nice bubbly sorbet.

Advise please

Jorge

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Check out the Martha Stewart video with Heston Blumenthal linked above in a previous post... he did it with the dry ice, but it didn't seem like he carbonated the ice cream - Martha and some other guy (maybe the producer?) both said it was really smooth textured, but no once commented on a fizzy feeling... it didn't seem like he added that much - and he didn't add it all at once either - he started the mixer then added a spoonful, the another spoonful, then another until he thought it looked right...

Another thing Blumenthal mentions in the recipe attached to the video is that the base should be chilled in the refrigerator before freezing with the dry ice... maybe that would keep it from getting to fizzy???

I'm going to try to do a test this weekend - will post how it goes...

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People around here are always making home made root beer for large gatherings and putting in the dry ice to cool and fizz it. No one ever thought about it not being food grade. Also, there is a commercial ice cream guy that goes around to parties and makes ice cream on the spot with Liq N. He stirs it up and flavors it in front of the guests. I have had it and it is very smooth. Here is his website.http://www.subzeroicecream.com/

[KennethT]

So, after some experiments, I came to a few conclusions...

First - my setup.... I had a couple of 5 pound blocks that were broken into small chunks... and then further broken by putting the chunks into a towel and hitting witha rolling pin until there was small pieces, and fine ice dust... I used a standard hand mixer on low speed using the egg beater attachments - in hindsight, not the best, but more on that to come... Total time from cream to soft serve ice cream was about 5 mintues....

Some things I found:

First, the base must already be COLD - like refrigerator temp cold... the reason is that when the dry ice hits a warm, or even cool base, it froths up for a while looking a little like Mount Vesuvius or one of those volcano science projects I did as a kid... much less frothing when the base was cold.

Also, my first experiment was using small pieces of dry ice broken from a large block... this proved problematic for a few reasons - sometimes the small pieces (size of a marble) would have cream frozen around it and you'd have to beat it apart with the beater... I was a little paranoid that there were small chunks of dry ice throughout so I beat it like crazy, putting in more air into the mixture than I'd like... it didn't come out carbonated, but it wasn't as dense as it usually is with the same base recipe...

I think the best way to do it, is to pulverize the dry ice into a powder - like snow... my first experiment did this by putting the dust/small pieces through a strainer to get only the dust... much better, more even distribution, and no worries of biting down on a chunk of dry ice! So that means less mixing, for a denser product - well, you could always whip it extra if you'd like, but I think it would be possible for a gelato like product this way... The chunks/pieces broke apart pretty easily -I haven't tried it yet, but it seems that it would work fine if put in the food processor - maybe even the blender...

All in all, it was pretty good - not hte best ice cream I've had, or made, but an interesting experiment...

[flacoman]

Started with the mix still warm and was relying on the dry ice to freeze things. It did that , but it dissolved too much CO2 into it. I did crush the dry ice but just tossed it into the bottom of the mixer bowl. Still a lot of good clean fun.

Wednesday i'm going to try sorbet with the same technique.

Tnx to all

Jorge

Edited September 29, 2008 by flacoman (log)

[KennethT]

So I tried this again the other night and came up with a slight problem... I started with base that had been sitting in the refrigerator for 24 hours, then added, a bit at a time, powdered dry ice (that had been sifted through a strainer to remove any pea sized pieces) and stirred with a wooden spoon - total freezing time about 5 minutes...

I then served it straight from the mixing bowl - soft serve consistency...

The problem was that it came out slightly carbonated... does anyone have any thoughts as to a way around this? I wonder if I let it set in the freezer for a bit if it would lose the carbonation?