Freezer Temps and Yeast
So, I run a large commissary kitchen. We shape and freeze about a thousand croissants a week. Most of these are baked and delivered within 3 to 4 weeks of shaping. We HAD been keeping our freezer at +5 to 10 degrees. With ZERO issue. Our owner, who knows nothing of food/baking, decided we needed to be somewhere in the -20 range. We complied. That was dumb.
We noticed some really stunted product. The older, the worse.
I've just googled/read for about an hour and haven't really found anything definitive. We are possibly moving into frozen, case packed, thaw/proof/bake product to be sold wholesale. Is there, in fact, a cold limit? If so, where is it and is there anyway to combat it? Is dry or cake yeast better/worse? Is there an additive or super cool chemical you can add to dough to help?
Thank you and may the baking gods look down upon you with favor.
... is indeed what's harming your yeast (which isn't proven but it makes sense), then death of individual yeast cells would be the actual problem, and there is no chemical capable of resurrection from the dead - not even for yeast. As amount time in the excess cold goes on, more and more cells might be dying, creating the time-based drop in activity that you're seeing.
The prime solution would obviously be to put the freezer back the way it was when things were working.
Second might be to rearrange your stock somehow so that the super-cold freezer contains only those things that can withstand it, and other items (including yeast) are somewhere else.
Sorry - are you talking about frozen packs of yeast, or frozen pre-proofed croissants?
If your looking for information on deeply frozen food products, you could always contact your state's extension service. Most of them are located at the state university that has the largest agricultural curriculum . Here in Kansas, it's Kansas State University and in the Lone Star State, it's Texas A&M. Besides developing cooperative programs for 4-H, county fairs, and local extension service offices, they do serious work in food science. Usually, they're more than happy to help out. The Bread Bakers Guild of America might also be able to help you. They do a lot of work with the artisan bread community of businesses and have long established connections with the companies that make the products that both commercial and home bakers use.
OTOH, if you've kept track of the quality of product from both freezer settings, you can always present that to the owner and convince him based on costs. Money does, after all, talk.
When considering dry vs cake yeast, a lot of bakers prefer cake yeast because they feel it generates more CO2 in their mix. However, cake yeast has a much shorter shelf life. Instant dry yeast is popular because it's fairly consistent in quality, can be stored at home freezer temperatures for years, and can be measured quickly and easily. It does have some practical aspects that are appealing to a commercial venture. Doing a side by side test of your products using both yeasts should tell you whether one or the other results in a superior taste.