Sometimes a pinch of salt is added to a cup of coffee - but why?
Is this only done for low-quality or mediocre coffee? When is the best time during the coffee-making process to do this?
I'm not a coffee drinker, so can't comment on the timing -- but it's due to salt's effect of masking bitterness.
This is common practice in places like Ethiopia, where it is used (much like Americans use sugar) to cut the bitterness. This is a longstanding cultural practice (they domesticated it, so I figure they probably know better than we do), in an area where sugar was not readily available. In this situation, it is added just prior to drinking.