<Tr> <Td_colspan="2"> (edit on Wikidata) </Td> </Tr> <P> Burping (also known as belching, ructus, erupt or eructation) is the release of gas from the digestive tract (mainly esophagus and stomach) through the mouth . </P> <P> Burping is generally caused by swallowing air when eating or drinking and subsequently expelling it, so in this case the expelled gas is mainly a mixture of nitrogen and oxygen . Burps can also be caused by drinking carbonated beverages, such as beer, soft drinks, energy drinks, and wine in which case the expelled gas is primarily carbon dioxide from the drink itself . Common diabetes drugs metformin and Byetta can cause burping, especially at higher doses . This often resolves in a few weeks . Burping combined with other symptoms such as dyspepsia, nausea and heartburn may be a sign of an ulcer or hiatal hernia, and should be reviewed by a physician . Other causes of burping include: food allergy, gallbladder problems, acid reflux disease, H. pylori, and gastritis . </P> <P> The current Guinness world record for the loudest burp is 109.9 dB, set by Paul Hunn on 23 August 2009 . This is louder than a jackhammer at a distance of 1 m (3 ft 3 in). </P>

Where does the sound of a burp come from