Starter wort slow to get moving (3724)

Viability may be low enough that it takes more time than you think to show signs
It's possible, if your fridge is like mine, sometimes things freeze and thaw without noticing. (Lettuce shows this better than most things.)
Stirplate?

 

Only if the jar froze. It's hard to say if all 100% of the yeast died but it definitely will influence viability of it spent time frozen. I'd say give it another day and look for signs.

 

I don't have first hand experience with long term yeast storage but I think they normally store it in a solution that does not crystallize. I think freezing in water is an issue.

 

After 3 months, there is probably still live yeast, but there may not be a lot. I agree with scurvy311 to wait and see what happens.

 

Freezing yeast (without special preparation) will kill some of the yeast. I once had yeast that I was pretty sure froze and thawed on its way to me. I used it anyway, because one of the yeast manufacturers said that most of the yeast would have survived. It was true... they definitely grew in the starter and then fermented the beer. But I got slight fusel alcohols (or something with a similar hot taste) in the finished beer. And it was a lager, fermented at 50F. It was probably the 6th or 7th time for that recipe, with the same process. I can't say the off-flavor was because of the freezing/thawing, with n=1 and all that. But I was quite surprised.

 

I haven't worked with yeast first hand. but, when I work with bacteria in the lab and we need to have long term storage, in -80C freezer, we have to suspend them in a special solution. Otherwise, in regular water, the cells will crystallize and most would not survive the freezing / thawing.

 

I would say yes and yes (at least for another day).

Three months makes it old . . . but not decrepit. My older yeasts have a longer lag time, but never 24+ hours. Unless your liquids are regularly freezing in your fridge I can't imagine your yeast are damaged this way.

Room temp is about 80 in my house . . . I hope you're pushing at least high 70s. Are you sure about the 3 months? If older than this you may have so little yeast that there will be little activity and wouldn't be surprised if it came and went quickly (as in overnight). Did the quantity of slurry appear to increase or any aromas present (other than starter wort)? Have you tried cutting off the stir plate for an hour or two, then giving it a hard shake and seeing if it off-gases? There will be no harm in stepping it to another starter . . . maybe keep it the same size or smaller.

 

What kind of activity are you expecting?

I've made starters where no appreciable krausen was observed ... yet
... its gravity indicated there be fermentation
... when the surface was viewed at an oblique angle ... CO2 be actively breaking the surface

!RDWHAHB!

 

I second the recommendation to take a gravity reading if you can. I had an almost 3 month old jar of 3274 start a little slow on me, but still produced one of the best saisons I've made. If potentially freezing is an issue, can you move your yeast storage to a better regulated kegerator/ keezer? I would count that as a pro tip because it also makes my wife much happier to not have yeast cluttering up our regular fridge.