if you burp and some saliva comes up too with the burp (less than a mouthful) and you intentionally swallow it, and on swallowing it you find the taste of the saliva is bitter, is that saliva counted as vomit or not?
Al-jawab billahi at-taufeeq (the answer with Allah's guidance)
This saliva is not saliva rather vomit. The fast is only broken if one had vomited a mouthful involuntarily and swallowed it voluntarily or if one had voluntarily (induced) vomited a mouthful whether swallowed or not. (Fataawa Hindiyya - vol. 1, pg. 203/4).
The definition of “mouthful (vomit)” is that which one cannot hold back in one’s mouth without difficulty. (Nurul Idhah Pg. 35)
If this was less than a mouthful then the fast did not break.