I think I've killed my yeast!

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Alastair70

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One of my more recent ordering ingredients while hammered cockups has come back to bite me.
I thought I had ordered the all the stuff for an amber ale brew, but accidentally re-ordered the grains, hops and wy2308 for a German lager brew instead.
This was then left in the kitchen for 4 days before I opened it and discovered my mistake. The yeast has been in the fridge for 2 months now, I smacked the pack 2 hours ago, but there's no sign of swelling up to indicate viable yeast activity. On the other hand, it's a lager yeast so 2 hours is not a great deal of time compared to an ale equivalent. I do have some Lallemand diamond lager yeast on standby.

Would you make a starter and give it a go, or dump it and use the dried instead. I'm leaning towards the latter, I really don't want to crack the first Oktoberfest open at Halloween and discover it's honking.
 
Personally, I really hate throwing things away. Four days at room temp isn't incredibly long and when you spotted it, you popped it in the fridge. I've have plenty of smack packs do fine without swelling, but I've given them at least three or four hours and also some shaking. As long as you're not intending to underpitch, I'd give the smack pack a go. If you don't see any activity in 48 hours, use the backup.
 
Right. Super starter made, 1.5L at 1.060 as its a lager yeast that’s probably feeling a little tired and emotional. I’ll give it until Sunday night to pull itself together.
 
I make my starters around 1.030 or less and build them up to final strength. It puts less stress on the yeast particularly if it is dubious.

I've not seen any advice to make a starter so strong, you want the yeast to get going and not be stressed or get a competitor in there whilst it's waking up and getting going. Personally I'd dilute it down and add more sugar later but you might not have a big enough vessel for that.
 
Err.... not wishing to be a Casandra here, but.......
Two weeks ago I started a golden ale using Wyeast 1728 Scottish. I've used this before, and I like it for malty beers with no real phenolic yeast input to the flavour. Very clean indeed at the low temperatures I typically use. The pack was well in date, and I "smacked" it and left at 20°C overnight. To my surprise, no real swelling by the morning. So, I shook it - and heard a reassuring fizzing sound. It still didn't swell much though. A couple of times later in the day I shook it again. Once more, I could hear fizzing, but the bag only swelled very slightly.
Anyway, i thought it was obviously working, containing live yeast, so I pitched it. The beer was sluggish to ferment, with a very long lag phase, but did get going after a couple of days.
The result is terrible! A huge antiseptic (almost TCP) flavour. And I mean huge! I can only see the whole brew (now a month old) being poured down the toilet.
I assume that something happened to the yeast in transit - too high a temperature somewhere? Anyway, i guess the yeast was terribly stressed, and I will never again use a Wyeast pack that is extremely sluggish to get going !!
 
@Hoppyland agreed your yeast does sound a failure, but you don't seem to be following the manufacturers advice!

Smack pack.JPG


No real surprise the yeast was stressed and couldn't perform optimally or even to average.
I'm not sure of your OG or volume or did you oxygenate.

I do always smell the yeast before pitching it whether from the pack or after building a starter.
 
@RoomWithABrew 1.060 is upper limit of SOP, so single step starter seemed reasonable. Last time I used this strain it was with an older packet and the same volume and gravity starter worked fine. I’ll be checking final gravity of the beer on Sunday night and tasting it before pitching. It’s in any way iffy it’s going down the sink.
@Hoppyland TCP taste implies a phenol, we’re you using a POF yeast? I’ve had it once with a wild yeast infection on a Kolsch brew which I eventually tracked down to the inside of the tap on the FV, and once with a stressed out wy3068.
 
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Err.... not wishing to be a Casandra here, but.......
Two weeks ago I started a golden ale using Wyeast 1728 Scottish. I've used this before, and I like it for malty beers with no real phenolic yeast input to the flavour. Very clean indeed at the low temperatures I typically use. The pack was well in date, and I "smacked" it and left at 20°C overnight. To my surprise, no real swelling by the morning. So, I shook it - and heard a reassuring fizzing sound. It still didn't swell much though. A couple of times later in the day I shook it again. Once more, I could hear fizzing, but the bag only swelled very slightly.
Anyway, i thought it was obviously working, containing live yeast, so I pitched it. The beer was sluggish to ferment, with a very long lag phase, but did get going after a couple of days.
The result is terrible! A huge antiseptic (almost TCP) flavour. And I mean huge! I can only see the whole brew (now a month old) being poured down the toilet.
I assume that something happened to the yeast in transit - too high a temperature somewhere? Anyway, i guess the yeast was terribly stressed, and I will never again use a Wyeast pack that is extremely sluggish to get going !!
That sounds as if an infection got into your brew while the yeast was still weak. I confess, I've had it twice over the last 5 years (since I've been in France, in fact). I now build my "starters" by not pitching until the fermentation in the flask is very vigorous and then I pitch into a half-batch of 10 or 12 litres. The top crop or cake is then used to inoculate a full size brew. That's if I'm growing the yeast from the dregs of a bottle or from an out of date commercial pack. If it's good and fresh, my starter can go into a full batch straight from the flask.
Pitching weak yeast is always risky.
I should add that my starter medium is around 1040 made from adding 10g malt extract per 100g water, and that my half-batches are between 1040 and 1050, certainly no higher than that. The yeast should then be numerous and healthy enough to pitch into just about anything.
The Australians have the best way of making starters: they use a 1½ or two litre PET and put the medium in there and give it a good shake, squeeze out the remaining air and then let some fresh air in and shake it vigorously again before adding the yeast culture. This ensures a richly oxygenated growth medium. It's not so easy to do that with a two-litre Erlenmeyer flask, but for those committed to stir plates, you can pour the medium from the PET into the flask and away we go. (Really must try a stir plate sometime, but I love swirling the flask by hand every hour or so).
 
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accidentally re-ordered the grains, hops and wy2308 for a German lager brew instead. This was then left in the kitchen for 4 days before I opened it and discovered my mistake. The yeast has been in the fridge for 2 months now, I smacked the pack 2 hours ago, but there's no sign of swelling up to indicate viable yeast activity....

Would you make a starter and give it a go, or dump it and use the dried instead. I'm leaning towards the latter, I really don't want to crack the first Oktoberfest open at Halloween and discover it's honking.

4 days at UK ambient is not going to do yeast huge amounts of harm. Remember that we ferment ale at 18-20C not because it's the biological optimum, but to minimise off-flavours. Ale yeast would much rather be growing at 30C or so and don't die until you get into the 40sC - which you might get in a van left out in the sun during a heatwave, but not otherwise. True, lager yeast are a bit more temperature sensitive than that, but should still survive low-mid 30sC.

@RoomWithABrew 1.060 is upper limit of SOP, so single step starter seemed reasonable. Last time I used this strain it was with an older packet and the same volume and gravity starter worked fine.

There's a difference between "I got away with it" and best practice.

I'm with RWAB - just generally, I'd make my final starter somewhere between 50-70% of the gravity of the target wort, and I wouldn't make my first starter more than 1.040, certainly not if there was any question over the viability of the yeast. If those two ranges overlap, then you only need one starter - I very seldom brew over 1.055 or so, so it's not a problem for me.
 
Well, it appears I’ve grown an imperial ton of yeast. No off aromas, going to switch off the stir plate later, cold crash tomorrow and check the beer for off flavours. If all good, I’ll pitch 2/3s of it on Monday and save the rest for Munich Helles brew that’s lined up end of June.

So, I’ve had two goes at killing yeast and failed, once with heat wave kitchen temps and once with gratuitous starter abuse. By way of penance I’ve ordered Chris White’s Yeast on Amazon.

Before and after pics (the photos do not do justice to the actual amount of yeast in there)

AEE500B5-4EFC-48B1-8C5D-24BB15D1FF52.jpeg
3E754F8E-A5A6-404D-8F6E-C904723880DF.jpeg
 
@Alastair70
Those chunky bits all look good, quite a dark malt for the starter ?
A really healthy starter before I let it settle decanted and pitched, 1.040 and left for 36 hours at 18 celsius.

IMG_20210529_181242.jpg

Ended up with 15mm of yeast in the bottom that was mixed with 250ml of the residual liquid.
Going great guns within 12 hours, Wyeast 1098.
IMG_20210531_084627.jpg

I have backed the pressure off since this photo to 4 psi.
 
I was all out of DME so used medium spray malt for the starter as it was what I had on hand. The Oktoberfest is going to be about that colour too, so thought the yeast would enjoy the similar wort.
I really have to stop doing my ordering when I’ve got a load on!
 
Well, it appears I’ve grown an imperial ton of yeast. No off aromas, going to switch off the stir plate later, cold crash tomorrow and check the beer for off flavours. If all good, I’ll pitch 2/3s of it on Monday and save the rest for Munich Helles brew that’s lined up end of June.

So, I’ve had two goes at killing yeast and failed, once with heat wave kitchen temps and once with gratuitous starter abuse. By way of penance I’ve ordered Chris White’s Yeast on Amazon.

Before and after pics (the photos do not do justice to the actual amount of yeast in there)

View attachment 48152View attachment 48153
2308 flocculates hard and fast like a snowstorm in a flask; it's one my reliable stalwarts for anything German because of the rich, full malty flavours it brings out. That starter looks fine. Very good in fact.
 
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