I think what is happening is, since you are trying to
swallow the saliva frequently, you are also swallowing
air. So, you have more air in your stomach and that's
why the excessive burping.
Now, why is it that you have excess saliva?
Some people chew gum more frequently. This act of
chewing produces more saliva.Certain spices can make
you produce more saliva.
It is better to have adequate saliva that contains enzyme
which helps to digest starches or carbohydrates.
If you have GERD, you might experience heartburn
Caffeine,tomato and citrus products will make it worse.
If there is damage to the lining of the esophagus
trouble swallowing. Some people have sore throat
and cough at nights. If you have any of these, you need
treatment after evaluation.
I wish you well.