# Ice cream

#### NeoDevin

I believe the salt allows the water (ice) to be liquid at less than 0C, thus improving the cooling process.

#### Jimmy Snyder

How long does that last step take?
About 7 years I think. But if you only count the time we spent rolling the can, I think it was 15 minutes. Here is an example of instructions. They can be found all over the net.

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#### BobG

Homework Helper
How long does that last step take?
In an ice cream maker, somewhere between 20 minutes to half an hour (very roughly), depending on how much you make. I have a gallon can, but 3/4 of a gallon is the most I can make if I really want a good consistency to my ice cream. I only make 3/4 of a gallon if it's a large group. Half a gallon would normally be the most you want to make.

The more salt you add, the lower the melting temperature of the ice and the faster the ice cream freezes. Too low of a temperature, though, and you start to get ice chunks in your ice cream - crystallized ice chunks of the mixture, not water. You want a nice creamy texture which means the entire mixture has too cool at about the same rate, hence cranking the beater blade through the mixture. You can shorten the time it takes to freeze by adding more salt, but you better crank faster, too. You don't want the mixture at the outside of the can to be much colder than the mixture in the center of the can.

If it doesn't get really hard to crank no matter how long you crank, it's because you didn't add enough salt. You need to add some more. Provided you didn't waste all of your ice using too high of a temperature, starting out with too little salt doesn't hurt the ice cream - it just makes it take a lot longer. Running out of ice because you didn't add enough salt means the ice cream is still too soft to put in the freezer. The ice cream will settle and you'll get some ice chunks.

I can understand Moonbear's comments about all homemade ice cream not being very good, because there's a lot of ways you can mess up the texture, especially when you first try getting the feel of just how much salt you need.

I mean, let's face it, some people can't even handle toasting a marshmallow. They get impatient and char the outside while leaving the inside raw.

#### fourier jr

I believe the salt allows the water (ice) to be liquid at less than 0C, thus improving the cooling process.
I'm pretty sure that's the reason. I've seen Heston Blumenthal make ice cream in a regular Kitchenaid stand mixer using chunks of dry ice.

#### turbo

Gold Member
BobG is right. My family would make ice cream in pretty large batches, with low temps, but they would also hijack us kids to crank the mix as fast as we could, and get relieved by fresh kids eager to make a high-quality product (and eat the same!).

#### mgb_phys

Homework Helper
I believe the salt allows the water (ice) to be liquid at less than 0C, thus improving the cooling process.
Dissolving salt in water is endothermic (most solid solutes in liquid are) so it will provide a cooling effect - this was necessary in the days before freezers.

#### Evo

Mentor
It's a shame that with all of the electric countertop ice cream makers that most of the younger people here will never know what it's like to make ice cream in a hand cranked wooden ice cream maker. As a kid, that was one of the biggest thrills of summer. Word that you were making ice cream spread like wildfire and within minutes every kid on the block would be there.

#### Moonbear

Staff Emeritus
Gold Member
Too low of a temperature, though, and you start to get ice chunks in your ice cream - crystallized ice chunks of the mixture, not water.
...

I can understand Moonbear's comments about all homemade ice cream not being very good, because there's a lot of ways you can mess up the texture, especially when you first try getting the feel of just how much salt you need.
Yeah, that's probably what happened. I remember it being rather "chunky." :yuck: I vaguely recall the recipe requiring eggs too, and I don't think my parents understood the concept of tempering eggs, because I remember also having bits of cooked egg throughout the mixture. Bleck!

I mean, let's face it, some people can't even handle toasting a marshmallow. They get impatient and char the outside while leaving the inside raw.
Hey! That's the way I like my toasted marshmallows!

BobG is right. My family would make ice cream in pretty large batches, with low temps, but they would also hijack us kids to crank the mix as fast as we could, and get relieved by fresh kids eager to make a high-quality product (and eat the same!).
Apparently, we needed more kids living nearby. I remember very tired arms. :uhh:

#### fourier jr

Dissolving salt in water is endothermic (most solid solutes in liquid are) so it will provide a cooling effect - this was necessary in the days before freezers.
I think I've heard that people used saltpetre in water. Would that have worked even better than rock salt? I have a feeling that it may have, and now it's considered too dangerous to use when making ice cream, or corned beef.

#### Ouabache

Homework Helper
I've enjoyed many a batch of hand-cranked ice cream.. (using a White Mountain Freezer-6qt). It has a triple mixing system with the crank operating two sets of beaters, moving in opposite directions and at the same time, the can revolves in opposing direction. If you're interested in some background about these freezers, here's a reference.

The hand-crank models are nicely portable and is ecologically friendly using only people power. Besides making ice cream in the backyard on sweltering summer days, I've made ice cream this way, at outdoor music festivals, drive-in movies (there are a few drive-ins still around), and even on camping trips. One camping trip, I didn't have enough rock salt but did happen to have a sack of soluble granular fertilizer in the car and realized it would depress the freezing point of ice too. The ice cream came out fine! (I made sure to keep the fertilizer/ice mixture below the lid of the can).

If you've never seen hand-cranking in action, here a nice clip of an ice-cream crank off, held in Mckinney,TX.

#### Ouabache

Homework Helper
I'm pretty sure that's the reason. I've seen Heston Blumenthal make ice cream in a regular Kitchenaid stand mixer using chunks of dry ice.
He has made ice cream using liquid nitrogen as well. (talk about freezing the cream quickly ). As long as you mix it thoroughly, after adding the liquid nitrogen to the mixture, it will come out with smooth consistency. On this clip (in which he also makes bangers & mash and treacle tart), at 3:50, he begins discussion on making ice cream. If you like that one, you ought to catch his clips on the chemistry of chocolate. :tongue2:

#### Math Is Hard

Staff Emeritus
Gold Member
It's a shame that with all of the electric countertop ice cream makers that most of the younger people here will never know what it's like to make ice cream in a hand cranked wooden ice cream maker. As a kid, that was one of the biggest thrills of summer. Word that you were making ice cream spread like wildfire and within minutes every kid on the block would be there.
I remember working hard for my ice cream. *crank crank crank crank crank* phew!

#### Math Is Hard

Staff Emeritus
Gold Member
He has made ice cream using liquid nitrogen as well. (talk about freezing the cream quickly ). As long as you mix it thoroughly, after adding the liquid nitrogen to the mixture, it will come out with smooth consistency. On this clip (in which he also makes bangers & mash and treacle tart), at 3:50, he begins discussion on making ice cream. If you like that one, you ought to catch his clips on the chemistry of chocolate. :tongue2:
mmm.. bangers n' mash ice cream! That sounds even better than chicken ripple.

#### fourier jr

mmm.. bangers n' mash ice cream! That sounds even better than chicken ripple.
That's not as crazy as you think! At his restaurant a regular menu item is bacon & egg ice cream.

#### Math Is Hard

Staff Emeritus
Gold Member
That's not as crazy as you think! At his restaurant a regular menu item is bacon & egg ice cream.
My brother would love that. He's a bacon freak.

#### Ouabache

Homework Helper
I remember working hard for my ice cream. *crank crank crank crank crank* phew!
Yep, builds good muscle tone in the arms.

Math Is Hard said:
mmm.. bangers n' mash ice cream! That sounds even better than chicken ripple.
You're funny :rofl:... check out the clip.. this fellow knows his craft, he is making a high quality vanilla ice-cream

Evo said:
The best ice cream I've ever tasted was home made (by me), ice and rock salt in a wooden bucket, hand cranked. People that had never tasted home made ice cream before were going nuts. I have never found a mass produced ice cream that could match that flavor....
I'm with you, hand cranked in the wooden bucket is great.. The slow consistent turning makes a frozen creamy ice cream. :tongue2:

turbo-1 said:
There is a family that owned a local dairy, and about 25 years ago, they couldn't sell enough butter to get rid of all the milk-fat that they removed from milk to make reduced-fat milks. They opened a small ice cream shop, and started making ice cream to sell locally. It became a huge hit...
I wonder what town they're in, I'd like to stop by sometime and try it.

#### Evo

Mentor
I remember working hard for my ice cream. *crank crank crank crank crank* phew!
Ok, it was hell cranking that ice cream out, but in the end, you were so relieved that it was ready that it tasted like the best thing in the universe!

#### Moonbear

Staff Emeritus
Gold Member
Ok, it was hell cranking that ice cream out, but in the end, you were so relieved that it was ready that it tasted like the best thing in the universe!
Oh, now I understand the psychology in action here. Homemade ice cream tastes so good because you're so hot and tired from the cranking that anything cold and containing sugar would taste good.

#### hypatia

The thought of cooked eggs in ice cream has made me a little queezy:yuck: Poor moonbear!

#### rewebster

I bought some 'store sold' ice cream about 2 weeks ago for the first time in maybe six months and noticed it was 25% smaller than the last time I bought it ---it was 1 1/2 quarts-----not the half gallon that it had been (since eternity began)---what a bummer---can't say "pick up a 1/2 gal. of ice cream" anymore

Gold Member

#### fuzzyfelt

Gold Member
Oddino's in London is really nice. You can watch the ice-cream being made through a glass window. The especially green coloured pistaccios come from Sicily. The Basil flavour is great, and so is the cinnamon.

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