Crystal Sizes: Salt comes to you in crystals. These crystals can be of different sizes depending on how the salt was prepared. Everyday table salt tends to be of a very specific crystal size. Coarse, kosher, sea and other salts come in different crystal sizes. Now, I know what you are thinking. What difference does it make? One, the larger the crystal the faster and easier salt will dissolve in water, but the slower it will dissolve on the surface of meats. Two, the smaller the crystals the heavier salt is by volume. Now, that’s the real key here.
Size Matters: Let me explain. One cup of normal, everyday table salt can weigh twice as much as some brands of kosher salt. So imagine that you have a cookie recipe that calls for 1 tablespoon of kosher salt and you put in one tablespoon of table salt. You just added twice as much salt as necessary. You could end up with some salty cookies. Similarly when we mix up brines to make a better turkey (pork tenderloin, chicken, etc.) we need to make sure that we add just the right amount of salt. We do this by weight, not by volume.
Which Salt: I said that some brands of kosher salt can weight half as much as typical table salt by volume. One of the problems with kosher salt is that it isn’t as consistent by weight. So why use it? Kosher salt is very pure salt. No additives are added to prevent caking and no iodine is added to keep your thyroid happy. This means it gives us one of the purest options to put salt and only salt into our brines. We choose the flavors, not someone else. If you want to use a different kind of salt, that’s perfectly up to you, just weigh it before you use it.
How Much Salt? : The traditional brine is made from a ratio of 1 cup of salt to 1 gallon of water. This is based on table salt. 1 cup of table salt weighs in at 10 ounces. So we want 10 ounces of salt (by weight) per gallon of water. Kosher salts can weigh between 5 to 7 1/2 ounces per cup, so in these cases we would need between 2 cups to 1 1/2 cups of kosher salt per gallon of water. The two most popular brand of kosher salt weigh in like this: Morton Kosher = 7 1/2 ounces per cup and Diamond Kosher = 5 ounces per cup.
So regardless of the salt you prefer, choose a salt that is pure for your next brine. Once you have the basic formula together you can add your sugars, herbs, spices and whatever else you put in your brine.