Farting jokes and cracks in the breakroom.?

I have this disgusting boss that is always talking about farting and stuff like that in my work's breakroom. He has even let one a couple of times. I think this is totally unproffesional and disgusting when people are usually trying to eat. What is worse, he has got to where he asks me if I am the one who let the "latest one." I don't do that in public, nor do I discuss personal business like that. I have to work under this guy a lot of the time, what should I do?