Belching ! 35 yr old man continously belching frequent, loud & long. how to make him stop? revolting!?

boyfriend to daughter. doesn't matter if casual visit or holiday meal with lots of people. daughter seems to think he just has alot of gas from an akaline body. I find it discusting, rude and very childish as he apparently has less control of his bodily functions than a 5 year old. He knows that I don't like it but continues. May as well throw in disrepectful. Sign me frustrated.