Both sea salt and food grade rock salt consist mostly of sodium chloride, which means that their flavors are almost identical. Even so, there are some significant differences between them. In this SPICEography Showdown, we’ll compare these two types of salt below and consider how interchangeable they really are, along with the best ways to use each of them.
Is there a difference between the flavor of rock salt and the flavor of sea salt?
The flavor of rock salt is simply salty. The saltiness is clean with none of the notes that you might get from the additives found in most table salt. The fact that the granules are larger means that less rock salt will fit into a cup when compared to sea salt. In other words, you will get a less salty flavor from a cup of rock salt when compared to a cup of sea salt.
Sea salt also has a clean, salty flavor but with briny notes from the traces of minerals that it contains. The cleanness of its flavor comes from the fact that it undergoes less processing when compared to other types of salt.
Can you use one as a substitute for the other?
Rock salt has a chunky texture, which is what makes it useful for culinary applications like making ice cream and being used to make a crust on certain foods. You can grind it, which will give it a texture more akin to those of kosher salt or table salt. You can then use this salt in any application that calls for sea salt. It will work in the sense that it will give food a salty flavor; however, it will lack the flakiness and oceanic notes that make sea salt a desirable option.
The delicate flakes are what make sea salt special and they can be used in place of rock salt’s chunks. They work in most rock salt applications in that you can use them to form a crust on food and for making ice cream. That said, sea salt is much more expensive than rock salt. Using sea salt in the same way that rock salt is used will be cost-prohibitive in most cases.
When should you use rock salt and when should you use sea salt?
Rock salt is best for applications where the size of the grains will be beneficial. When making ice cream, rock salt is added to the ice to lower its freezing point. The result is that the ice gradually melts and transfers its energy into the cream, which causes it to freeze. The freezing occurs at a slower rate than it would in a refrigerator, which allows the water in the cream to freeze gradually and have a soft texture instead of a hard one. Any type of salt will have the same effect, but the large grains of rock salt are best since they spread evenly in the ice.
Sea salt is the better of the two options in any kind of cooking because of its flavors and grain size. Its texture complements everything from salads to seafood and it can give a pleasant crunch to food when it is used as a finishing salt. It does not have to be altered, unlike rock salt that must be ground to be used in many culinary applications.