Pre-expanded yeast pack

I purchased an out of date Wyeast pack that looks like it had already been smacked. I shook the packet, and it sounds like the yeast pack inside has not been popped yet. Is there any chance the yeast leaked out, or could this pack be infected?

It’s my understanding that the pack inside is wort. Not yeast. ... oductID=16

If it’s popped or not, I’m not sure how you tell by the sound of it.

Make starter and see how it smells/tastes. Of course it may smell/taste bad and still be good.

Unlikely it’s contaminated from the lab. I would brew with it.

I always do a starter. I just wanted to be prepared if I had to pour the yeast pack directly into the starter solution.

Sometimes a swollen pack can be caused by a small amount of sugar or CO2 being left in solution at the time of packaging. CO2 can be released from solution or the yeast can consume the sugar and create a small amount of CO2.

Wyeast has a nice FAQ on their site .

It says the yeast is in the main solution, not the inner pack:

[i]1. Is the yeast in the small inner packet or in the foil pouch itself?

The yeast is in the main foil pouch. The small inner packet contains the sterile nutrient and wort that feeds the yeast before it is added to your fermenter. First, the package and the nutrient packet are sterilized (autoclaved) then the yeast is added and the package is sealed. [/i]

I’ve had this happen a few times before. Doesn’t seem to hurt anything. I always make a starter, so I knew the yeast was viable.