yeast activation

I have activated Wyeast 3944 Belgian Wit dated 26 April 2012, which I am using for my Belgian White all grain and I will be using a yeast starter. The packet was activated and sitting in a room in which the temp is 72 degrees. The packet is still not fully inflated and when shaken I hear it fizzing, almost sounding like a soda can when poured into a glass; thus my concern is rather I should use this yeast or not.

If its inflated a half inch it's good to use, a starter will also confirm viability. That being said I would not use yeast that old regardless, I would be shocked it it had anything left alive in there.

When I plug the date into brewers friend yeast pitch calc it says the viability is 0% so I would just buy new yeast.

My gut was telling me that the yeast was bad. Thanks for the confirmation.

If it inflated a little bit that would indicate there is at least some viable yeast in there. You could probably make it go if you babied it a bit. For example, pitch it into a small volume, then progressively step it up to batch size.

But that might be more trouble than its worth. But that might be the kind of trouble you like....it never seems to amaze me how homebrewers like to make things more complicated than they need to be!