Have you ever had a bad vial of Yeast?

[Redmond_Fil]

I brewed 10 gallons of an Amber Ale on Saturday. Split the batch in into two 6 gallon fermenters (when I say split - I mean I used a tee junction so it really is exactly the same wort in both fermenters). Into each fermenter I pitched one vial each of WLP005 that had warmed to room temperature over the preceding 3 hours. Aerated both fermenters and stored at 67 degrees. 24 hours later one fermenter is in high krausen - the other - nothing.

What happened? I've always had great results directly pitching the White Labs vials. I grabbed the vials from the trash and saw they were (a) not expired, but (b) from different production lots. I've never had a problem like this and lest there be any lingering suspicion that there was another undiscovered problem with the failed wort/fermenter - I re-pitched with 4 oz. of WLP002 thick slurry that I'd harvested from the last month's batch and fermentation got started within 6 hours. I suspect the yeast or its handling by the local HBS. What do you think?

Ps. I suppose this is also a cautionary tale that illustrates the value of using a starter in all cases.

 

[Calder]

4 ozs of 1 month old slurry and it took off within 6 hours! I think the original pitch of WLP005 is what is doing the work. 6 hours is quick for 1 month old slurry. Now if it was 4 ozs of washed yeast from slurry, that may be different.

You didn't mention how long you waited after the initial pitch before declaring it dead.

I always use fresh slurry or make a starter with a new pack, so I know everything is OK. I have never had a bad pack of yeast.

Since the yeast was from different lots, and probably different dates, there may be a difference in how they start up.

 

[Redmond_Fil]

Great questions.

I only waited another six hours, then prepared the yeast for pitching.

The yeast had been thoroughly and properly washed and carefully stored. I've frequent good experience with this approach and my fermentations reliably start with in 6 hours when pitching according to the Mr. Malty guidelines. Pitching from White Labs vials I reliably get fermentation started with in 12 hours.

I suppose it's possible that the WLP005 was getting ready to take off but given the reliability of my experience with my harvested yeast it's likely that any WLP005 still hanging around was out competed by the WLP002.

 

[estricklin]

Great questions.

I only waited another six hours, then prepared the yeast for pitching.

The yeast had been thoroughly and properly washed and carefully stored. I've frequent good experience with this approach and my fermentations reliably start with in 6 hours when pitching according to the Mr. Malty guidelines. Pitching from White Labs vials I reliably get fermentation started with in 12 hours.

I suppose it's possible that the WLP005 was getting ready to take off but given the reliability of my experience with my harvested yeast it's likely that any WLP005 still hanging around was out competed by the WLP002.

To elaborate slightly on what was stated above; the reason why we make starters ISN'T because there isn't enough yeast cells in a fresh vial/smack pack to get the job done, it IS to take that variable of bad vials and improper storage out of the equation. I live in Arkansas, and in the summer I never order liquid yeast online, I've been burnt too many times, so to answer your original question, yes, I've had a bad vial.

On the other hand, I can understand why a person would pitch a vial straight into wort without making a starter, it's very convenient. in the instances where I need something right here and now, I turn to dry yeast. I keep it around in case of emergencies, as in "Why isn't this fermenting yet?". Truth be told, 24 hours isn't that big of a deal, but around day 3 I would certainly think about pitching some additional yeast.