That sounds like a problem with the trap or the vent stack (or both). Odors shouldn’t be able to come up from the drain.
I wonder about this as well. I always rinse Cannellini beans and black beans but have never noticed any odor from the sink after doing so.
Why run to the bathroom? Just keep an old jar handy, pour the liquid in that, and dump it in the toilet next time you happen through there.
Ditto. I rinse in the sink all my canned beans. No odor problems. There’s no reason there should be.
You could pour it in the trash can. That might be a worse smell though. And leaky. I never pour oily or greasy things down my drain. I save old food containers and pour them in, and throw the closed container in the trash. You good try that.
I’ve found that there is less gas when I rinse them and dispose of the water, actually quite a bit less gas. I’ve heard that that substance is water soluble so does dissolve into the water. IDK if that is true, but yes it does seem to work.
If you “have” to rinse the beans, do it in the sink and run a piece of citrus rind through the disposal.
I don’t even have a disposal, but just rinsing them in the kitchen sink should work fine (I actually just did it now). I don’t understand why there is any sort of smell coming up. The P-trap should block any downstream odors. I guess if some gets caught up before the P-trap it could stink up, but I’ve never ever had that issue. This is just odd to me.
The OP is talking about the water from a can of beans. I think it might be too salty for what you’re suggesting.
I agree. I do know a bit about that stuff. I even commented to my wife that the whole idea of a P-trap is to prevent that. That said… it is happening. Today I used some liquid drain cleaner in case the problem stemmed from a clog of some sort (crossing fingers).
While the OP wasn’t interested in this, others might be, so I’ll note that it’s literally the water from a can of beans (or chickpeas, as in this article or this one or this one).

I’ve found that there is less gas when I rinse them and dispose of the water, actually quite a bit less gas. I’ve heard that that substance is water soluble so does dissolve into the water. IDK if that is true, but yes it does seem to work.
Cooking also breaks down some of those substances.