Yeast Didn't Fire

[flattop]

4th batch of Dr Smurto's using harvested us-05 harvested yeast cake, it's been in a stubbie in the fridge for around a month.
Pulled it from the fridge about an hour before pitching ( a bit less than usual) then pitched the stubbie... next day no activity, no condensation on the gladwrap, no krausen, nada.....
Pitched a second stubbie today just to be sure to be sure...

Otherwise it's out with the dried yeast packet tomorrow.... unusual though, usually my yeast harvests work fine, perhaps the lower temps are preventing a fast kick off, my house is heated to around 18* in the evening but overnight it can drop to 12* inside... I may have to invest in an immersion heater or heater pad to get the job done

 

[Sammus]

Wow a month? If I had a bottle of trub in the fridge for any more than 2 days I'd definitely make a starter before using it.

 

[Stuster]

Only two days! Wow, that's even more extreme than Jamil Z. :huh:

I've certainly used older yeast slurries than that and they've been fine. Nowadays I do make a starter if they've been kept for more than 2 weeks but I still think you should be fine. It's probably the colder temps making for a slow start. US-05 is a hardy beast though and should be fine at those temps. I'd wait another day and see what happens. Maybe put something around the fermenter to keep it warmer at night as well.

 

[Sammus]

Even better, 2 hours! I either reuse trub straight away or build a new starter from a slant. Maybe I'm not the best person to listen to about this stuff

 

[Tony]

I remember many years ago Mel Robinson from ESB telling me not to keep slurry from a dried yeast more than 10 days. He said liquid yeast is ok but something about the drying process............ not sure of the science of it but its a rule i have always set for myself.

These days i just pitch fresh dry yeast....... i dont even keep it. Its just not worth the risk for saving a dollar or 2 when you making premium beer for 50c a glass.

I split a wyeast smack pack into 3 or 4 test tubes and grow them from starters. and i dont bother saving them either once brewed.

I have had this happen before. The slurry usually goes off like a frog in a sock and then one day............. its just dead!

I think Mel said it mutates faster or something.

Each time you reuse it, the yeast changes. Dominent cells will dominate and if these are more suceptible to shock from temp change or something like that......... well i think there was something in what Mel told me.

cheers

 

[flattop]

yes i've used a month old yeast before with no drama's, usually though i have left it out of the fridge for a few hours to condition.
My feeling is that the fridge is probably colder now being winter and shitefully cold in Melbourne at night now and the daytime temps are mid to low teens.
The ducted is raising the temp to around 19* for about 6 hours a day, the rest of the time it's chilly....
I think it's not the yeast failing to fire but the temps slowing it down....

 

[Stuster]

Tony, there used to be concerns with dry yeast about it not being as clean as liquid yeast. The issues with contamination are not really there any more, so use that slurry from dry yeast just as you would with liquid yeast.

The advantages I see with using slurry over using dry yeast are that you have far more which can be very important if you are making a beer. Also, many yeasts apparently work better on a re-pitch than straight out of the packet/vial. At least this is that I've read. I'm not sure I can tell as I haven't done side by sides to prove this, but they certainly don't seem to work worse and my feeling is that this is right and I think that's a more important point than saving the money (although that's handy too).

 

[Screwtop]

4th batch of Dr Smurto's using harvested us-05 harvested yeast cake, it's been in a stubbie in the fridge for around a month.
Pulled it from the fridge about an hour before pitching ( a bit less than usual) then pitched the stubbie... next day no activity, no condensation on the gladwrap, no krausen, nada.....
Pitched a second stubbie today just to be sure to be sure...

Otherwise it's out with the dried yeast packet tomorrow.... unusual though, usually my yeast harvests work fine, perhaps the lower temps are preventing a fast kick off, my house is heated to around 18* in the evening but overnight it can drop to 12* inside... I may have to invest in an immersion heater or heater pad to get the job done

You joined this forum in Oct 2008 _ you must realise the importance by now of proofing yeast before use and about the importance of maintaining stable fermentation temps.

 

[flattop]

Yes i realize the importance of yeast firing, but being time poor sometimes i have to take a punt, i have 3 kids and a full time job and a house falling down around my ears so I do what i can handle- in the time frame i have.
As a rule i don't proof yeasts, my strike rate is pretty good, i would say my slurry usually fires within 24 hours 99% of the time....

As for stable temps, lower temps are less of a problem than higher temps (once the yeast has fired) a range between 14* and 19* is not going to present a major issue in fact it's probably the best range, a slow ferment is often desirable.
I have had one yeast not fire before and I'm not concerned about this one as yet, as i said i think it's just slow not dead, i am simply posting my experiences....

IF pitching dry yeast i usually re-hydrate, i don't proof that either, i rehydrate wait an hour or so and pitch....

Anyhow it all adds to the fun
As i stated earlier i have a sachet of US-05 on standby should the need arise

 

[jimi]

You joined this forum in Oct 2008 _ you must realise the importance by now of proofing yeast before use and about the importance of maintaining stable fermentation temps.

ahh the old "You should know by now, that you should know by now!" advice. If theres another more uplifting peice of advice, I've yet to hear it