First of all, my thanks to you for taking part in this forum. Awhile back, your always helpful Sigrid Gertsen-Briand mentioned to me that preliminary trials at Lallemand had suggested that freezing dried yeast was not good for the yeast in some way. Anecdotally, some homebrewers and winemakers have mentioned that they have no problems using dry yeast that has been stored in the freezer.
Could you please expand on this and let me know if any additional work has been done on this topic?
- Brian Lundeen
The original research on Active Dry Yeast shelf life stability was done over 60 years ago. The interest at that time was stability at room temperature (20C) and at refrigerated temperature (4 C). The dry yeast was not designed with freeze storage in mind. No real studies were made on storage in a freezer.
We have found out recently that many people have been storing our Active Dry Yeast in freezers for years with no apparent adverse effect. A preliminary freeze storage trial with one of our strains indicated some damage was done. This may indicate that the damage might be strain related. It is too early to draw any conclusion. We will continue to investigate. Thanks for your interest. We will keep you posted.
Dr. Clayton Cone