What's that nasty creamy white stuff that comes out of ...

[LPCTech]

Apparently it is Albumin. Coagulated proteins.
Same for Salmon as Chicken.

http://www.huffingtonpost.com/2015/01/30/white-stuff-salmon-how-to-avoid_n_6564634.html

 

[Ruptga]

Dude...did you troll the archives just LOOKING for something like this for your first post?

Well, that is what spammers do.

 

[GagHalfrunt]

Is there a way to prevent it from not coming out?.

Try thinking about baseball. And also try investing in a course on English as a second language.

 

[who?]

If more fat leaks out before you cook the chicken, it may be rubberier.

 

[Fritzo]

It's basically microscopic amounts of fat supsended in the meat's juices.

There's no way to stop it really. Just scrape it off.

Well, it's protein, not fat. It usually happens when chicken has been frozen. Injected chicken is more likely for this to happen. You can prevent it by slowing thawing chicken before using it.