Several things can cause it; 9 times out of 10, you see this on epoxy or sealer put on mixing system and some lids will let solvents escape and tuning machine off and on all day long helps the solvents escape.
Next, if when can first be opened if excess pigments on the bottom of the can dont get mixed in right, then going forward, the pigment load is too heavy for the resins that are left; this is more common with epoxy.
The next thing is excessive temps for an extended period of time when stored in unstable temps.
Such as 35 in the morning and 50 in the afternoon or 40 to 60, not necessarily freezing, but it takes many days to cause this, not one or two weeks.
The excellent news is pigment does nothing but give color, so produce is fine, just dirty, and you cannot strain it out or mix it back in.