It is not from the sunnah to burp out loud purposefully. Rasool Allah صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ said the one who eats onions and garlic should not join the congregational prayer. This was because of the bad odour from eating them.
There is no dua for burping in our tradition rather the focus is on not having a smelly breath and on burping out loud and causing discomfort to those around especially so during salaah.
Shaykh Yahya Ibrahim answers and explains...
No transcription found