I subjected fresh roasted coffee to a vacuum chamber, with the hopes of accelerating CO2 off gassing. It was a natural Sidamo. The vacuum was about 26-20 inches Hg.
The coffee that was in the chamber for about 9 hours had less perceived acidity and
less aroma but more body and a longer, sweeter finish, compared with the same batch of roasted coffee that was not in the chamber.
The brew method was French Press. The coffee exposed to the vacuum chamber had less off gassing when I added the hot water to the press.
Myself and 3 others tasted it with very similar comments regarding acidity and flavor, about 24 hours after it was roasted ( earlier today ); we have an air roaster.
I know this is not very scientific but I am so excited by the stark differing results that I had to post this.