My mom had the same issue... since she had us in her 20s. She is in her 60s now. She just had to stop drinking pop. You might be out of luck :(
Isn't that funny? I have the exact opposite problem. I can't burp ever, it's not something my body ever learned to do. Except now that I'm pregnant and suuuuper gassy I burp all the time. It's so weird what growing another body in your body will do to its ability to function normally.
I have a similar feeling sometimes i can get the burp out and other times if I try to hard I'll vomit a little in my mouth. Gross!
I had that problem often during my first pregnant. So far not this time around.