I am not anti-coffee hack. I love a good coffee hack. So I was surprised that it took me until this year to hear about an apparently long-standing practice some people swear improves their coffee: putting salt in it.
No less than Alton Brown recommends the practice of adding salt either to your grounds or to a brewed cup, claiming it will “cut the bitterness of coffee, [and] it also smooths out the ‘stale’ taste of tank-stored water.” He recommends adding only a pinch of salt, not enough to imbue your morning cup with any noticeable salinity. The premise is that salt, even more than sweetness, tempers bitterness. (The precise mechanics of this are still mysterious.) But that’s about as far as most salting-coffee articles go: They claim some people enjoy it, but they’re scant on scientific explanation or sensory analysis as to why this happens. I tried it myself, and can’t say I noticed much difference in the flavor or bitterness of my coffee, either black or, as I usually take it, with a splash of cream.