I am spitting out some sort of particle from throat from some days. This happens once in a while. I am not sure if it is a food particle stuck in food pipe that comes out or tonsil stone. Attaching picture for reference. Sometimes it get stuck in throat give heavy feeling in throat and cause irritation/choking type of feeling. Please advise for the cause and treatment. Other issues: White bubbly mucus after eating food or after hot drinks very frequently. Acidity/Gas/Indigestion sometimes.