After a conversation with Lance Shaner, Owner of Omega yeast, the following was added to the FAQ section of their website:
My pack of yeast is swollen. Is the yeast still good to use?
Swelling of the pack is not an indication of a problem with the yeast. It is the result of slow fermentation of residual fermentables during storage. The yeast is still perfectly fine to use (assuming it is within date and has been stored properly).
A unique Saccharomyces strain that produces delicate, tart, tropical mango and pineapple fruit characteristics with a clean finish. Try higher fermentation temperatures to really bring out the tropical aspects. It’s stubbornly non-flocculent, but the results are worth the trouble.
This strain tests positive for the STA1 gene, an indicator of Saccharomyces cerevisiae var. diastaticus, and is capable of fermenting dextrins, resulting in very high attenuation.
70–85° F (21–29° C)
We strongly recommend purchasing an ice pack with your liquid yeast to help maintain a reduced temperature during shipment.