Question about Fermento

[polarlys]

I have some Fermento.  It's been around awhile and caked up.  I was wondering if this stuff has a shelf life and if it's still good to use.  I've never used it and also wondering what time of meat processing I would use it in.  I guess I need to do some reading up on the subject.  A friend gave me this along with quite a bit of Prague #2 also.  That I'm more familiar with. 

 

[MudFarm]

Not sure about the caking but a couple guys I work with use it for summer sausage and love it.