I always freeze unused egg whites to use at a later date, but if I have yolks left over I throw them out because I'm never sure if it's safe to freeze them or not. Am I wasting them for nothing? is it okay to freeze egg yolks? I guess I'm more wary of yolks because I know they're more likely to harbour bacteria than whites.
It is OK to freeze egg yolks, I did read that you can mix them with either salt or sugar (depending on how you plan to use them later), this apparently helps to emulsify them. Hope that helps.