Much like wine I find coffee such an unpredictable thing taste-wise. For example, yesterday I made myself an early morning ristretto which was amazing, sweet and smooth. Exact same extraction (and beans) this morning and it tasted quite bitter. I hadn't eaten or brushed my teeth before either.
90+% of the time I love what I make but there are occasional weird times when it tastes unpleasant. Perhaps something else more subtle is going on but I've never managed to link anything to it. Apart from wine I don't get wild differences in taste with other foods.
Just curious if anyone else has the same experience with coffee ... or is it just me?