Would this work better with calcium chloride instead?
Why do we salt the ice when making ice cream?
61–70 of 111 posts
Re: Why do we salt the ice when making ice cream?
#62Surely part of the issue is that the ice at If you add ice you reduce the equilibrium temp and as a result the < 0C ice temp can be passed to the liquid phase and as a result on to the inner con tain er where you're making the ice cream
it's not just the coldness of the ice, salt dissolving in water actually decreases the temperature, it's an endothermic reaction. the salt dissolving into the water brings the water down to 0... omg time for Farenheit to shine... brings the water down to 0F without freezing it (because of the lower equilibrium temp), which is -17.8C (Farenheit uses this endothermic salted water temp as its definition of 0, I think be…
I understand Fahrenheit now.
Re: Why do we salt the ice when making ice cream?
#63Now check out Eutectic mixtures ... old-timers may remember soldering with 63-37 tin/lead solder. The reason? With any other mixture of lead/tin, the liquid solder freezes over a temperature range, often resulting in what very-old-timers called a "cold solder joint". For example, 50-50 tin/lead mixture starts melting at 183C and is fully melted at 214C. Using Eutectic Solder, the phase transition happens at exacctly…
Without lead you get tin whiskers. I wonder how the math works out in terms of what’s better for the environment if electronics break a lot more often…
Re: Why do we salt the ice when making ice cream?
#64Earlier quoted context omitted.
That's true of the surface of the ice, but the core is colder
For a little while, yes. Ice has middling thermal conductivity, it'll eventually homogenously warm to the melting point.
yes - then it wont be ice any more - but while there's still ice the temp of the liquid will stay at the equilibrium point - after that it will start to warm
Re: Why do we salt the ice when making ice cream?
#65Or put the simpler way: salt makes the icewater colder than 0C, and cream needs to be about 0F to freeze.
The ions from the salt get in the way of water molecules aligning to crystallize into ice. When salted ice melts, the water can't refreeze as readily because the saline isn't pure water anymore and because the freezing point is colder. As more ice melts, more heat is absorbed, bringing the temperature down even lower. (https://www.thoughtco.com/how-cold-does-ice-get-with-salt-40...)
Re: Why do we salt the ice when making ice cream?
#66Now check out Eutectic mixtures ... old-timers may remember soldering with 63-37 tin/lead solder. The reason? With any other mixture of lead/tin, the liquid solder freezes over a temperature range, often resulting in what very-old-timers called a "cold solder joint". For example, 50-50 tin/lead mixture starts melting at 183C and is fully melted at 214C. Using Eutectic Solder, the phase transition happens at exacctly…
Without lead you get tin whiskers. I wonder how the math works out in terms of what’s better for the environment if electronics break a lot more often…
A giant pile of scrap electronics is probably easier to deal with than a very large pile of scrap electronics that's leaching toxic heavy metals into the ground and runoff water.
Most electronics these days seem to get upgraded before tin whiskers can cause problems anyway.
Re: Why do we salt the ice when making ice cream?
#67Adding salt to an ice and water mix in a cooler is a known trick in hotter countries. Makes your beer cool down faster, and can get it down to -2C, the sweet spot for light Pilsner.
Re: Why do we salt the ice when making ice cream?
#68Earlier quoted context omitted.
A bit of alcohol would achieve that too right? Eg rum&raisin ice cream
Right, alcohol, sugar and salt all change the hardness of the ice cream but you can only add so much until the flavor isn't what you want anymore. I don't think the ice cream texture is due to the melting point, though, that the post talks about, it's also whether large enough ice crystals can form. It feels like cheating but adding stabilizers (gums, mostly) was really a game changer for our homemade ice cream.
Which texture hacks have you played with besides xanthan gum?
Re: Why do we salt the ice when making ice cream?
#69Earlier quoted context omitted.
Ah, I had no idea that's what they put in there. Xanthan gum is pretty amazing
It's amazing how potent that stuff is. You only need 1/8th of a teaspoon of the powder per drink. I tried using a whole teaspoon once but it was so thick that I couldn't get my coffee through a straw.
Hahaha I made the same mistake making a thc syrup. Ended up ‘one lump or two’!
Tiny amounts needed.
Re: Why do we salt the ice when making ice cream?
#70Earlier quoted context omitted.
For a little while, yes. Ice has middling thermal conductivity, it'll eventually homogenously warm to the melting point.
yes - then it wont be ice any more - but while there's still ice the temp of the liquid will stay at the equilibrium point - after that it will start to warm
"then it won't be ice anymore". Not so: the freezing point is the temperature at which ice and water are in equilibrium. If you take a bowl of ice to its freezing point it will still be entirely frozen. Then if you continue adding energy, it will remain at its freezing point while progressively more of it melts, i.e. going from 100% ice to 50% ice/50% water to 100% water. All at one temperature. In other words, if you are at the freezing point, then all of the energy you add goes to melting the ice (and none of it goes to increasing the temperature), until all of the ice is gone. That is the case even if you wait to true equilibrium, e.g. for all temperature gradients to go away.