Throat deposits. Known about such thing?

I see white deposits deep down on the backside of throat wall... Not sure if that's in fact in the food pipe mouth itself. As such it is not troublong me. But I obsevered it around a year and half back. I did not find any information about it on web. Is there anything known about such thing? I am trying to find more because I have been getting throat infection frequently since last couple of years and it takes weeks to recover. Doc says it just due to weather change or eating outside or cold drinks which somehow I m not able to accept as I used to not had to visit doctor for years and suddenly it has changed. Trying to find out if white deposits as I explained above has anything to do with reoccurring throat infection.