Shelf-Stable Half and Half - How stable? At my place of employment, they supply coffee.  Along with cups, lids, and sweeteners they provide the little plastic containers of half and half.  The box these come in states, "No Refrigeration Necessary."  The date on the box is usually a few months into the future. 

Occasionally, I will find what appears to be curdles in the half and half.  Has it really curdled or is it more of a settling or congealing in the half and half?  

These "curdles" are small, white, and float in the coffee.  The larger "curdles" do not dissolve when stirred.  I think I have noticed an odd/off taste but I don't use half and half consistently so I'm not sure if it's due to the "curdles".

So, how stable is this type half and half?
Will it get REALLY chunky if left long enough?
If the curdles swim on top and are without much structure it is likely milk fat.
If they are fluffy it could be proteins.

Breakdown due to germs is unlikely as a shelf life of several months wouldn't be possible with fresh milk. Manufacturing errors excluded.