From here. Yeah, I know. In space no one can hear you burp. I don’t know anything about anatomy, but something about this claim seems wrong to me. I know flatulence is caused by a by-product of digestion, and burpiness is caused by the swallowing of air while eating, but doesn’t the air have to go somewhere? Is gravity the only thing that seperates the air from the food? Not to be crude or anything, but if the air remains mixed with the food during every step in digestion, do astronauts then excrete fecal mousse (pre-emptive BAND NAME!)?
Astronauts do burp in freefall, but it’s gross:
So it seems that the gasses do separate, at least for carbonated beverages, and maybe for any other foods as well, but the gas doesn’t float to the top of the stomach.
I see. Thank you, Podkayne. I tried googling astronauts and belching and got a bunch of hits about belching stars and belching rockets and ancient astronauts with belching aircraft.
Now I’m wondering which is worse, fecal mousse or wet burps; but I think that’s an issue I’m going to have to work out on my own. 
I thought they just farted it out. All the other astronauts might get mad at him for a while,then move over to the other side of the ship till the room aired out. but hey, when nature calls you gotta go, right :eek: