When they are feeding they take in air, and the air creates the 'Gas' the burping releases it, if it sites there it actually causes some discomfort,so it is good to feed then stop sit baby up holding the hand on the chest and firmly rub the back, in older babies patting helps. If you are breast feeding here is a tip, if you have plenty of milk you will know that it spurts out when you go to feed especially if it has been a few hours, so you may want to express a little off first, to slow the flow ,otherwise baby very often cant gulp it down that fast and they throw it back up...