The next step involves salting the curd. Aside from adding flavor, salt is a critical component to the cheese-making process.

Salt Reduces Moisture

Cheese is ready to eat when it has the right flavor, moisture, and texture profile. Achieving the right balance of moisture and solids is one of the final and most critical stages. Left alone, a block of curd will lose only about 60 percent of its moisture. During aging, too much moisture can lead to unwanted bacteria or fermentation. However, if salt is added to the curd, additional moisture is drawn out, and a naturally balanced and safe aging cycle can proceed.

Salt Creates Surface Rinds

Surface-ripened cheeses such as Parmigiano-Reggiano develop a rind of dehydrated cheese, which in turn protects the rest of the cheese from being penetrated by unwanted bacteria or other organisms. Surface rinds are created by salting the curd, and either packing and rubbing wheels of curd in dry salt while they age, or immersing wheels in brine for a few days or weeks.

Salt Keeps the Cheese Clean

If you've ever had salt water splashed on an open cut, you know how much it stings. The sting is created by the cleansing power of salt to rid a cut of germs. Likewise, salt in cheese acts as a major deterrent to the development of unwanted bacteria, which in turn allows cheeses to enjoy long, graceful periods of aging.

Salt Enhances the Flavor

Finally, salt has a significant effect on the flavor of cheese, not only because it enhances the flavor of the curd, but also because it melds with the curd to create microbe and enzyme activity that, in turn, create the very special flavors unique to cheese.

How Salt Is Applied

There are three basic methods of adding salt to curds. Curds can be dry salted before being pressed into forms, or dry salted after being pressed into forms. Curds can also be immersed in brine, and it's not uncommon for cheese makers to use a combination of these techniques to produce their cheese

Coarse salt is most commonly used because it absorbs gradually. If applied before pressing the curds into forms, it is sprinkled on evenly cut pieces of curd, stirred into the curd, and reapplied until the desired amount is incorporated. If applied after pressing, salt is sprinkled on the outside surface of newly formed cheeses and serves to draw the moisture to the cheese's surface, where it forms a brine, some of which evaporates, and some of which is reincorporated into the cheese.

When salt is applied through brine, the curd is immersed in a bath of brine for anywhere between a few hours and up to several days. During this time, the brine bath is carefully monitored and modified to allow for the appropriate exchange of things being leached from the curd (primarily lactic acid and calcium), and things being added to the curd (salt and desired microbes).