Acceptable Liquid Yeast Age

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Brew_DD2

Mint Choc Chipster
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Received a delivery of yeast (amongst other things today) and was quite surprised to see that one of the yeasts had a manufacture date at the start of April 2019 giving it about 18% viability. I have no issues making a starter I just thought that was quite an old pouch to be receiving. It'll take a few steps to get it to where it needs to be.

At what point do you think that homebrew stores should advise the customer that the yeast is of a certain age/viability.
 
Received a delivery of yeast (amongst other things today) and was quite surprised to see that one of the yeasts had a manufacture date at the start of April 2019 giving it about 18% viability. I have no issues making a starter I just thought that was quite an old pouch to be receiving. It'll take a few steps to get it to where it needs to be.

At what point do you think that homebrew stores should advise the customer that the yeast is of a certain age/viability.
It should be advertised on their website as OOD and usually reduced in price accordingly and if not I would contact them to let them know.
If they are reputable they will offer discount or replacement.
 
It should be advertised on their website as OOD and usually reduced in price accordingly and if not I would contact them to let them know.
If they are reputable they will offer discount or replacement.

That's why I am asking as it isn't out of date as it still is relatively viable, and I am not expecting the yeast it be only a few days old. I was wanting to put the feelers to see what age does it seem unreasonable to sell without being clear about the yeast age? I am not particularly bothered about the cost, but I will have to do a few step-ups and had been planning to brew on Saturday.
 
Hi DD2

White Labs' BB dates are always 4 months after manufacturing date ... which suggests they believe 3.5 month old yeast should be OK to sell/use ... of course their other advice also suggests you should always make a starter, whilst also suggesting they sell directly pitchable amounts :?:

Cheers, PhilB
 
Hi DD2

White Labs' BB dates are always 4 months after manufacturing date ... which suggests they believe 3.5 month old yeast should be OK to sell/use ... of course their other advice also suggests you should always make a starter, whilst also suggesting they sell directly pitchable amounts :?:

Cheers, PhilB


That's right about where this Imperial one is. 200 billion cells may well be pitchable for an ale, but let's face it, none of us are getting the yeast when it has its full complement of cells. As this is a lager yeast I'll need about 400 billion so I was prepared to do a starter, but I'll probably need to do 3 steps with yeast this age.

Maybe just get two pouches next time.
 
Received a delivery of yeast (amongst other things today) and was quite surprised to see that one of the yeasts had a manufacture date at the start of April 2019 giving it about 18% viability. I have no issues making a starter I just thought that was quite an old pouch to be receiving. It'll take a few steps to get it to where it needs to be.

At what point do you think that homebrew stores should advise the customer that the yeast is of a certain age/viability.
Where are you getting 18% from? The calculator I always use shows 40% and a starter size of 2.5 litres for a 400bn cell lager starter brewed with a 200bn Imperial pack.
 
That site is giving me 42% viability!

https://www.brewuk.co.uk/yeast_pitch_calculator

BrewUK showing 18%
I would be 100% confident in building a starter based on that calculator. It has a 100% success rate in calculating starters that attenuate the beer or lager quickly and fully for me and the viability estimate is near enough what Beersmith also comes up with. It's up to you though!
 
I would be 100% confident in building a starter based on that calculator. It has a 100% success rate in calculating starters that attenuate the beer or lager quickly and fully for me and the viability estimate is near enough what Beersmith also comes up with. It's up to you though!


Cool that's good to know. A little disconcerting that there is such a big disparity between calculators. The Beersmith mobile app is wildly out. Shows 192 billion cells despite the package date being 9th April.
 
I'd let the place I got a three month old yeast from know I'm not happy about it. I'd tell them if I was at their store I would not have purchased it without a steep discount, but would have wanted one much fresher.
 
Tried a few other visibility calculators and they are all showing around 18-20% viability.

Said retailer has a blanket 25% off on liquid yeasts at the moment but I don't really seeing anything about it being older stock. Quote the opposite in fact. The Wyeast pouch I got has a mid-May date on it too. Not all that bothered about the price to be honest, but when you are time-poor and have a brew day planned, it's a bit of a bugger when you'll likely not be able to brew because you are needing to do a few starters.
 
Because of some "disruption" at home I've twice found myself using White Lab packs out-of-date. And I've still got one more a month out of date to use up. The starter gets an extra day on the stirrer to ensure it is starting, and I check the SG of the starter to be sure if has started (if the SG hasn't budged, nothing is happening yet). And they're always fine. I treat any pouch within a month of their "best-before-date" (i.e. still within) to the same treatment too.

Are people culturing the scrapes of yeast out of years old bottles wasting their time? Try telling them that.
 
Because of some "disruption" at home I've twice found myself using White Lab packs out-of-date. And I've still got one more a month out of date to use up. The starter gets an extra day on the stirrer to ensure it is starting, and I check the SG of the starter to be sure if has started (if the SG hasn't budged, nothing is happening yet). And they're always fine. I treat any pouch within a month of their "best-before-date" (i.e. still within) to the same treatment too.

Are people culturing the scrapes of yeast out of years old bottles wasting their time? Try telling them that.

I am happy that there will be plenty of yeast to get a starter going, just a little put-out that I'll likely need 2-3 steps rather than the 1 I had expected.
 
Hi DD2



... I struggle to empathise with those sentiments ... here we are in a world where thanks to companies like White Labs, Wyeast, Imperial, Omega, etc. (and we could even throw in Danstar, Safbrew, Mangrove Jacks and CML if you wanted) we homebrewers have access to a wider variety of yeasts than pro-brewers would have dreamed of not that long ago ... and now we're complaining that the pack might not have as many yeast in as we hoped asad.

To put this in context, tens of thousands of brewers worldwide will regularly pitch a 3.5 month old vial into their brews and make beer they're very happy with ... occasionally, a few of their ferments may "fail" and they'll come on forums like this and we'll say "should have made a starter", "if you're fermenting cold, should have made a bigger starter or used two vials" ... you have taken that on board, and recognised that in order to make the best beer you can, you would follow good/best practice and always make a starter and pitch a large and healthy population ... but come on!! Don't expect the manufacturer/retailer to have to fall in line with YOUR choice to follow good/best practice. :roll:

Cheers, PhilB
 
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... I struggle to empathise with those sentiments ... here we are in a world where …
Just in DD2's defence: We are also in a world with the likes of Amazon and same day deliveries. I'd be whinging if I'd got a yeast pack with only days to run until it's best-before. The likes of Tesco "home deliveries" might even point out you've got a product with a short "use-by" (don't think they do it for best-before"?) so to give you the option of turning it down.

Maybe in the back of my mind I don't agree, but my thinking is skewed now!
 
I'd be whinging if I'd got a yeast pack with only days to run until it's best-before
... hmmm, Yeah, I think I might whinge too, lots of us would whinge ... but then we'd either shake ourselves down and realise how unreasonable our whinges were, or some kindly soul would (metaphorically) put their arm around our shoulders and remind us of how our whinges were unreasonable ... and that's what I was trying to do in my previous post wink...

Ultimately, the product that the yeast labs are selling us, that we are buying, is ; i) a wide variety of particular strains of brewing yeasts, and even at 4 months old there will be a sufficient population to be sure that the VAST majority of cells in that pack are representative of the strain(s) that we bought; and ii) sufficient yeast to ferment up to 5 gals of wort, at up to 1.060 OG (and they probably add at "ale" fermentation temps, as they advise to either pitch two packs or start up at ale temps and chill once fermentation has started, if fermenting at cooler temps), and even at 4 months there will still be sufficient population in that pack to ferment that wort. It may constitute a "low pitching rate" (and lower than DD2, and you, and I (even) would want to pitch, ideally) but there'll be plenty of yeast to ferment that wort ... so, as far as I can see, what's being sold is precisely to spec :?:

And, Yes, Amazon and Tesco may well provide those services ... but let's not pretend that the users of them aren't paying for them ... when we push our way to the back of those packs in the supermarket to get the product with the latest BB date, we do know that we're (collectively) paying for packs that don't/can't get sold by the retailer, ultimately, don't we ... so I guess the question here is "Do we think ALL home-brewers should be happy to pay more for their yeast, so that SOME home-brewers can be sure they're getting sufficient yeast for them to not be inconvenienced by having to grow a starter (or two)?" ... and in that poll, I'd vote "No" wink...

By the way, you do realise that organisations like White Labs and Brewlab (in Sunderland) will produce you directly pitchable populations of yeast, sufficient for whatever pitching rate you specify? Such services are really intended for commercial breweries, but I'm sure if you contacted them they'd quote for you ... hint: you may find getting someone else to grow those starter steps for you, could be more expensive than doing it yourself :confused.:

Cheers, PhilB
 
Ultimately I'm not that bothered. I was planning on doing a starter anyway. Was more curious as to the etiquette of stating yeast age on retailer websites.
 
Hi DD2



... I struggle to empathise with those sentiments ... here we are in a world where thanks to companies like White Labs, Wyeast, Imperial, Omega, etc. (and we could even throw in Danstar, Safbrew, Mangrove Jacks and CML if you wanted) we homebrewers have access to a wider variety of yeasts than pro-brewers would have dreamed of not that long ago ... and now we're complaining that the pack might not have as many yeast in as we hoped asad.

To put this in context, tens of thousands of brewers worldwide will regularly pitch a 3.5 month old vial into their brews and make beer they're very happy with ... occasionally, a few of their ferments may "fail" and they'll come on forums like this and we'll say "should have made a starter", "if you're fermenting cold, should have made a bigger starter or used two vials" ... you have taken that on board, and recognised that in order to make the best beer you can, you would follow good/best practice and always make a starter and pitch a large and healthy population ... but come on!! Don't expect the manufacturer/retailer to have to fall in line with YOUR choice to follow good/best practice. :roll:

Cheers, PhilB


Not a case of wanting it now. More a case of being short on time due to work commitments and having to plan to brew another day because there is a lack of info from retailers on yeast age.
 
Hi DD2

I wasn't suggesting you were complaining that "you wanted it now" ... and I apologise, if you feel I was suggesting that ... I'd posted the video intending for it to be viewed as a metaphor for unreasonable expectations ... and to be clear, from an "etiquette" point of view ... when it comes to what constitutes reasonable expectations, I feel that so long as the yeast is within the BB date it's perfectly OK for the retailer to sell it tom me ... I recognise that, sometimes I'll get a pack that is only a few days or a couple of week old, but then sometimes I'll get something made nearly four months ago ... it's swings and roundabouts and if I was bothered by that, I'd probably go to a (physical) LHBS and check the date before buying, but then realistically I know I'd probably pay the premium for doing that (either in terms of price, or variety of availability) :?:

All in my honest opinion, of course, and I recognise that others may have other opinions :beer1:
Cheers, PhilB
 
No worries. The day I take The Simpsons in anything other than good humour is the day I should give up.

I don't mind so much that the age of the yeast can be variable, I just guess that in this day and age it would be good to have some predicability. Would be a good idea for sites to list the date so you know exactly what you are getting. We would expect no less with hops.
 

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