Does espresso taste better if it sits a minute or two?

[JimWright]

I've actually experienced something interesting in this regard and wondering if other folks have seen the same.

On my Profi, I have tried various temp management routines but consistently have difficulty avoiding the bitter first shot. However, I've noticed that if I let those shots sit for a minute or two, a lot of that harsh bitterness often goes away - sometimes, by the time I'm done grinding and pulling shot #2, shot #1 will not be quite as good as #2 comes out, but at least drinkable (esp. in a milk drink).

Whatever is making it harsh/bitter is aging out in part as it cools or degases. I'm sure it's heresy for me to suggest a shot gets better with a little time, but anyone else notice a similar effect?

[HB]

I haven't noticed that bitterness specifically drops off after a short rest, but I usually wait 20-30 seconds for the espresso to cool because distinct flavors are easier to discern. To me, a super hot espresso often tastes monotonic.

[cafeIKE]

Short summary on How Temperature Influences Our Taste

[JimWright]

So, just for clarity, this got transplanted from another thread differently titled - I think the conventional wisdom is that it's better served right away, at least for a proper extraction, and I don't think I've experienced this for extractions that were not at least a little bitter/hard edged to begin with.

Then again, who knows, it makes some sense that as the brewed espresso degases and some of the crema dissipates, some elements/gases other than CO2 may go with it, and perhaps some of these are responsible for bitterness (or other sometimes harsh elements of the espresso experience like astringency)...? Has anyone done any experimentation with respect to time to drink from shot completion?