Farting constantly in front your girlfriend, appropriate?

My boyfriend farts in front of me all the time. Its so gross and he laughs. I understand its a bodily function but its not like its a few time he slips. He does it in front of my family and its embarrassing. Ive asked him repeatedly to stop or take it to the bathroom but he just laughs at me. I wouldn't be so upset if it was a once in a while thing but its not.