Salt in beer is almost exclusively associated with the “rediscovered” German beer style, gose. In this tart, spicy, wheat style, the salt adds a nice, crisp, briny note to contrast the tart flavors. Typical gose recipes call for only about one-half to a full ounce of salt for a five-gallon batch. It’s generally added late in the boil, perhaps to maintain any subtle flavors that may volatilize off, but adding it earlier in the boil probably wouldn’t be detrimental. I would caution against including it in the mash, as it could affect mash enzyme activity in undesirable ways.
Since salt is used in a relatively small amount, a brewer can be forgiven for not giving too much thought to what type of salt to use. However, since it’s such a unique and signature ingredient of the style, it’s worth picking the right salt for a desired impact. You can find a ridiculous number of different salt varieties in the marketplace, and though all have a special use, some types are regarded for their texture and dissolvability on the tongue. Perhaps more refined palates can detect the nuanced textual differences from a fancy French sea salt in their gose, but I think for this conversation we can stick to varieties that can impact flavor and leave “dissolvability” comparisons to the foodies.
Kosher Salt
In a pinch (pun fully intended), kosher salt can deliver the desired goal of adding saltiness to a beer, and that’s about it. It doesn’t have the iodine or anti-caking agent (sodium aluminosilicate) found in typical table salt (DO NOT USE), but it’s almost singularly sodium chloride. It won’t provide any other minerality qualities that can enhance some of the desired malt flavors. It will quickly dissolve in the wort, so it can be added very late in the boil. Kosher salt is a serviceable alternative, but sea salt should be the first choice.