Why do you put rock salt in an ice cream maker?
Adding salt lowers the freezing temperature of the water and for wintery roads, it means that the water won't freeze as easily. For our ice cream, it allows the temperature of the mixture around the ice cream to get colder.
Sidewalk salt is also known as rock salt. It's unprocessed sodium chloride taken directly from the ground. Softener salt doesn't melt ice any faster than sidewalk salt. But using sidewalk salt in a water softener will cause big problems.
- If you own a water softener, you'll want to check your softener's brine tank a least once each month to make sure you have enough salt. Most water treatment experts recommend that the level of salt should be three to four inches above the water level in the brine tank.
- Epsom Salts are Magnesium Sulfate, MgSO4. I believe water softener is common salt or Sodium Chloride, NaCl. Very different substances. Water softener systems remove Magnesium, Calcium, Iron and other minerals from your water.
- A quick science lesson; basically, milk won't freeze at 0°C like ice does, so ice cream refrigerators typically require rock salt to lower the freezing point of water so that the products don't melt. If you use water softener salt in rock form, this will do nicely!
To make and pack up to 4 quarts of ice cream, you will need about 15 pounds of crushed ice and either 4 cups of table salt or 6 cups of rock salt. Refer to the table below for more information. Wash the beater (often referred to as the "dasher"), top and cream can well before using.
- The difference is in their chemical composition and how they work to melt ice. Rock salt, also known as Halite, is the mineral form of sodium chloride. Salt lowers the freezing point of water. Small amounts of salt partially melt the ice forming a brine (solution of salt and water).
- Cover and refrigerate 1 to 2 hours, or overnight. Page 7 Turn the Cuisinart® Ice Cream Maker on; pour the mixture into the frozen freezer bowl and let mix until thickened, about 30 to 35 minutes. The ice cream will have a soft, creamy texture.
- Adding salt lowers the freezing temperature of the water and for wintery roads, it means that the water won't freeze as easily. For our ice cream, it allows the temperature of the mixture around the ice cream to get colder. Since the ice cream isn't just water, it needs to be a little below 32°F to freeze.
Updated: 3rd October 2019