The primary difference is that "ice cream salt" is a coarser rock salt often labeled as not for human consumption, and surprisingly, it can be more expensive than regular rock salt.
While both "ice cream salt" and regular rock salt are essentially sodium chloride, they are used for different purposes and may have varying levels of processing and purity. It's a misconception that ice cream salt is a special type of salt specifically formulated for making ice cream.
Here's a breakdown:
- Ice Cream Salt (Rock Salt): This is a coarse grade of rock salt, primarily used to lower the freezing point of the ice water mixture in a traditional ice cream maker. The salt helps the ice water get colder than 32°F (0°C), which is needed to freeze the ice cream base. Some brands are labeled "not for human consumption," suggesting a lower level of purity.
- Regular Salt (Table Salt, Sea Salt, Kosher Salt, Rock Salt for de-icing): This encompasses various types of salt intended for culinary use or de-icing. The key distinction is the level of refinement and intended purpose. Table salt is finely ground and often iodized. Sea salt is harvested from evaporated seawater. Kosher salt is coarse and additive-free, preferred by chefs. Rock salt intended for melting ice on roads may contain impurities and is not food-grade.
Because "ice cream salt" labeled as non-consumable may contain impurities, it is not advisable to use it for cooking, even though it's basically rock salt. Regular rock salt, available for de-icing purposes and is not labeled as consumable, also should not be used in food.
In summary, while the chemical composition (sodium chloride) is the same, the grade of salt, intended purpose, and the addition of other components differentiate "ice cream salt" and regular salt. Therefore, it is advisable to use food-grade salt for culinary purposes.
