What Is Ice Cream Salt?

If you are thinking about buying an ice cream maker and are wondering which type to get, you may have a few questions about “ice cream salt”. What does it do? Is it expensive? Why do I need it? Etc. This article will answer those questions and more.

What is ice cream salt?

Ice cream salt is more commonly known as rock salt. It is the same chemical composition as table salt. Sodium Chloride. But the salt you purchase for making ice cream or melting the ice on your driveway or sidewalk should not be eaten. It may have several impurities and is not intended for human consumption.

It is usually clear or white but could be one of several other colors depending on the impurities present.

Rock salt (or “Halite”) forms isometric crystals. These crystals are larger than what you typically see in table salt. Their larger size results in them mixing better with ice cubes when you use them for making ice cream. (Fine table salt would more likely sift to the bottom of the can.)

What does it do?

Water freezes at 0 degrees Celsius (32 degrees F) Other solutions have different freezing points. The fat and sugar in the mixture you prepare for making ice cream requires a colder temperature to reach its freezing point.
Salt lowers the temperature at which water freezes. So when you mix ice and salt the resulting slushy brine is actually colder than pure ice would be. By surrounding the mixing canister in the ice cream maker with this super cold brine, you bring the temperature of the ice cream mixture down to its freezing point. Ice alone cannot do that.

Will table salt work?

Well, in theory it would because it is, after all, salt. The problem is that it is too fine. It would be much more difficult to get it evenly dispersed throughout the ice chunks. To get your ice cream to freeze evenly, you want to control for uniform temperature.

Where should I buy it?

Price and convenience are probably the two issues that will help guide this decision.

Let’s take a look at the convenience issue first.
How much rock salt do you need, and where will you store it? If you expect to make ice cream frequently, or if you live in an area where ice is a common problem on your steps or walkway, you may use a lot of rock salt in a short period of time. It would be inconvenient and inefficient to make frequent trips to the store for another small box of it.
Do you have storage space for a large bag of rock salt? A garage or a good-sized pantry?
If you use a lot and have sufficient storage space, you will probably want to go to someplace like Home Depot and grab a 50 pound bag. The last time I checked, you could get that for less than $10.

Price is going to vary considerably depending on amount and labeling. The large 50 pound bags are clearly the best buy per pound. At your local grocery store you can probably find a 4 pound box of “ice cream salt”. For some reason, the prices vary dramatically! I’ve seen them for as little as $1.60 and as much as $13.49.
If you don’t have a home improvement store near you, or you don’t want to buy a large amount, you may need to check several grocery stores in your area for the best price. Try places like Target or Kroger too. It appears that calling it “ice cream salt” has persuaded some retailers to put a premium price on it. Your best option is definitely the home improvement stores.