Salt
He who has salt has power. Take a look at history, and you will see that salt has long been viewed as a commodity. Not only does salt kill viruses and bacteria, but it is essential to life. Humans and other animals need chloride and sodium to survive. Without it, you will have frequent muscle cramping and other health issues. Humans also need iodine to prevent goiter, which is why iodized salt should be in your stockpile.
Salt can also be used to preserve meats and seafood. How does it work? Salt inhibits bacterial growth by forcing moisture from cells. This means you can store things like strips of chicken and fish or even pickle cucumbers and other vegetables.
Keep in mind that you are going to need different kinds of salt for various recipes. Iodized salt, for instance, cannot be used to pickle vegetables. For that you need pickling salt and herbs.
