Wow! I had forgotten that issue until right now!
First of all, congratulations on your decision and follow-through to change your life!
I remember being very concerned about the same thing. I asked my surgeon about it, and he seems very not concerned. So not concerned, in fact, that I thought he wasn't understanding my concern.
I then asked my pharmacist about it, and he explained pretty much what Leelee did.
I remember spending a lot of energy worrying about that particular function of my body. It wasn't happening often enough. It was too hard. Too loose (WAY too loose for comfort). The wrong color (due to my addiction to popsicles, there was a time when lime green was the color.) There was a short time when I actually considered that I might have to use adult diapers.
I finally came to realize that my body was not "normal" for years before my surgery, and that trying to compare what was happening to me with what was going on at 300 lbs was insane. So was trying to gauge what my body was doing against what other peoples' bodies were doing.
I made a deal with myself to stop worrying about that particular function unless and until I became ill from it. I never did get ill because of it, and I am now probably "normal" for me. (I won't go into detail.)
This is one of those things that's going to take care of itself, and you will probably find that it's different than it was before, but that different does not mean wrong or dysfunctional.
I found it more constructive to focus on what was going into my body than what was coming out.
Your mileage, of course, may vary.
Stick around and pay attention. You'll learn a lot, and perhaps avoid the pitfalls that plague some of us as we get further out.