A burp – sometimes called a belch – is nothing but gas. When you eat or drink, you don’t just swallow food or liquid. You also swallow air at the same time. The air we breathe contains gases, like nitrogen and oxygen.
Sometimes when you swallow these gases, they need to get out. That’s where burping comes in! Extra gas is forced out of the stomach, up through the esophagus (the tube for food that connects the back of the throat to the stomach), and out of the mouth as a burp.
Some kids find that drinking soda makes them burp more. If you’re thinking that it’s because these drinks contain extra gas, you’re right! The gas that makes drinks fizzy is carbon dioxide, another gas that can bring on big burps. Sometimes eating or drinking too fast can make a person burp because this can send extra air into the stomach. The same thing happens when you drink through a straw: extra air in = more burps out.
Burping is almost never anything to worry about. Everybody does it once in a while, and it’s very unusual for burping to mean something is wrong in a kid’s body.
For more on burps check “Why do I burp? on Kidshealth.org”
Answer provided by KidsHealth.org