even rapture (Piti) can show up in this way, so this is just a condition the practice can bring. If you keep going it will go away and sometimes come back again. I think many of the meditators are "disturbed" from this (swallowing then uncomfortable sensation in your throat). I still have this many times after five years of practice.
If concentration get deeper then even can come out from your mouth
So this is also just a condition worth to investigate.
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