yeast packet left at room temp for 6 hours. still good?

[dawn_kiebawls]

I went to the homebrew store today and picked up some grain, yeast and everything needed to finish off my keezer rebuild. In my excitement to get home and keep working on my keezer I completely spaced the fact that I HAD A BRAND NEW PACKAGE OF YEAST IN THE BAG THAT I LEFT AT ROOM TEMP!!

Yeast is WY1318, best by April 9th 2021 (seriously..6 months. I thought it was always 4). Room temp 75F. 6 hours sitting out.

I'm going to pitch it into a 1.060, 5 gallon batch Monday and was going to get a starter going. Should I adjust for the viability of the packet at all or just treat it as usual? I do not plan on overbuilding the starter

 

[IslandLizard]

Yeah, it's all fine. Yeast is not gonna die from that little excursion on the counter.

Expect around 125 billion cells being that fresh! That's very unusual, unless... they changed the monthly count of what's considered "best by". Production date is way more useful. Not just for yeast. Is there a lot# that can be traced?

Definitely make a starter as planned, and save some out for a next batch (Starter Gen 1).
In a pinch a vitality starter 4-12 hours ahead of pitching could be done instead.

 

[IslandLizard]

BTW, do smack it and give it a good shake, a few hours (2-5) before adding it all to the starter wort.

 

[dawn_kiebawls]

From what I can tell the lot# is 1002261 but I can't find anywhere to look it up. I do agree though. A packed on date is much better. I'm not sure why they switched.

Since this is such fresh yeast (unless you're correct and that they're just extending the best by date by 2 months) I think I will overbuild and store some (especially since I'm starting down the expensive path of NEIPAs). How do I determine how much I'm reserving? How much should I overbuild by?

Thanks!

 

[day_trippr]

fwiw, I over-build by 50% - ie, enough for the target pitch plus half that amount. When I use the stored yeast I repeat the same process, being sure to account for aging.

I use the Brewer's Friend starter calculator brought to us by @TxBrew...

Cheers!

 

[IslandLizard]

Since this is such fresh yeast (unless you're correct and that they're just extending the best by date by 2 months) I think I will overbuild and store some (especially since I'm starting down the expensive path of NEIPAs). How do I determine how much I'm reserving? How much should I overbuild by?

This is the yeast calc I use most often:
BrewUnited's Yeast Calculator
Always double check and adjust cell content where applicable, such as [starter volume]. Some of those cells change automatically depending on values in other cells, which can be a bit confusing or even annoying.

A DME : water ratio of 1 : 10 (grams : milliliter) gives you 1.037 starter wort.

And this calc, especially for the "Pitch from slurry" tab, when you make starters or pitch from saved slurries:
Mr. Malty
Just click through the Flash warning, it's safe.

I usually overbuild starters by at least 50-100 billion cells. My common starter size is 1.6 liter, since I use a shaker. Even in a 2 liter flask on a stir plate I would not go over 1.8 liters. You need some headspace.

 

[IslandLizard]

since I'm starting down the expensive path of NEIPAs)

Have you bought some hops by the pound from YVH? Many of last year's are discounted, IIRC.

With NEIPAs I often repitch from saved yeast cakes. Yeah, there is dry hop pulp mixed in but never had any issues with it.
I use 1/4 of a yeast cake in a batch of similar size and gravity. 5.5 gallon of 1.065 is my go to volume and gravity for those.

If it's older than 2 weeks in the fridge I make a vitality starter with 1/4 of the cake and pitch the whole starter.

 

[dawn_kiebawls]

I bought a half pound each of Citra, Galaxy and Mosaic. My purse strings are drawn pretty tight this year so I got enough for my first two attempts.

I'm playing around on BrewUnited right now and I'm not sure I'm understanding the overbuild calculator since it doesn't allow me to change values in either of the cells. It says for me to get the 212 billion cells I need for 5.5 gallons at 1.060. With a 3 liter (shaken) starter I will wind up with 285 billion. Does it make sense to reserve 2/3L and end up with 63 billion to reserve? Or am I way off and not using the calculator correctly? Thanks again

Edit: I think I'm getting the hang of it. I was just expecting a calculator to make it so I didn't have to do math on my own, which is not and never has been a forte of mine

 

[IslandLizard]

It does pretty much all the math for you.

1. What kind of vessel are you using for the starter? A gallon jug?
2. If you don't have one, you could use two 1/2 gallon growlers, instead.
3. You're going to swirl it every few hours?
4. You got any Fermcap-S?

Does it look like this:

That way we're counting on saving out about 76 billion cells (306 - 230 = 76). That's about 1/4 of the starter, or 750 ml, well mixed/homogenized before separating out.

Without cold crashing prior to pitching, that means you're pitching 2.25 liters (= .60 gallons) of weak starter beer into your batch. It will dilute your batch by about 8% (est.).

If you wanna stick to your 1.060 OG and 5.5 gallons, aim for brewing a 5 gallon batch at 1.065. After pitching you'll then have 5.6 gallons of around 1.060.

What fermenter are you using?
Volume?

Instead, you could do a "shaken-not-stirred" starter.
You may get more growth, but it needs more work.

 

[dawn_kiebawls]

It does pretty much all the math for you.

1. What kind of vessel are you using for the starter? A gallon jug?
2. If you don't have one, you could use two 1/2 gallon growlers, instead.
3. You're going to swirl it every few hours?
4. You got any Fermcap-S?

1) I use a sanitized 1 gallon distilled water jug
3) I'm quite diligent about shaking starters. I leave them on the kitchen counter and shake it every time I walk by (I've even gotten my wife to start shaking it to!)
4) I do not have any Fermcap-S
Does it look like this:
View attachment 702442

That way we're counting on saving out about 76 billion cells (306 - 230 = 76). That's about 1/4 of the starter, or 750 ml, well mixed/homogenized before separating out.

I got a little confused (maybe just lazy). That is the math I was expecting the calculator to do for me

Without cold crashing prior to pitching, that means you're pitching 2.25 liters (= .60 gallons) of weak starter beer into your batch. It will dilute your batch by about 8% (est.).

I was planning on swirling up the starter really well and pouring off the 750ml into a sterilized mason jar, before crashing and decanting the starter meant for the brew.

If you wanna stick to your 1.060 OG and 5.5 gallons, aim for brewing a 5 gallon batch at 1.065. After pitching you'll then have 5.6 gallons of around 1.060.

What fermenter are you using?

I will be using the 7g Fermonster converted to a closed transfer system.

Volume?

Instead, you could do a "shaken-not-stirred" starter.
You may get more growth, but it needs more work.

I do not have any extra time this week to add another involved task, I'm already spread entirely too thin! A regularly swirled starter will have to do this time around.


Thankyou for taking the time to hold my hand and answer my really dumb and basic questions. I really do appreciate the help, thanks!

 

[Northern_Brewer]

Room temp 75F. 6 hours sitting out.

It'll be fine. Remember that in the wild yeast feed on grapes etc that live in Mediterranean climates, the optimum growing conditions for most lab strains is in the low 80's. We only ferment at temperatures below optimum to avoid off-flavours, although those "off-flavours" are what they produce to attract fruit flies etc to spread them around the vineyard. So 6 hours is fine - it's not much more than you need for good practice in letting it warm up before pitching.

 

[VikeMan]

It'll be fine. Remember that in the wild yeast feed on grapes etc that live in Mediterranean climates, the optimum growing conditions for most lab strains is in the low 80's.

Even significantly higher, according to this paper:
https://www.mdpi.com/2306-5710/2/4/34/pdf

OTOH, yeast sitting at room temp with nothing to eat aren't better off (viability-wise) than they would be at colder temps.

So 6 hours is fine - it's not much more than you need for good practice in letting it warm up before pitching.

I agree that 6 hours isn't terrible. Not ideal, but also nothing to lose sleep over.

 

[Northern_Brewer]

Even significantly higher, according to this paper:
https://www.mdpi.com/2306-5710/2/4/34/pdf

??

I think you're misreading "Maximum growth temperature" - it's not the temperature of maximum growth, but the maximum temperature at which it grows, any higher and it dies.

Most labs grow their cerevisiae at around 28-30C.

 

[VikeMan]

I think you're misreading "Maximum growth temperature" - it's not the temperature of maximum growth, but the maximum temperature at which it grows, any higher and it dies.

Maybe. But take a look at the ethanol production vs temp in this doc.
https://www.lallemandbds.com/wp-content/uploads/2013/06/LBDSMascoma_ThermostabilityDocument.pdfPeaks at 95F.

Most labs grow their cerevisiae at around 28-30C.

I believe that. But I'm not sure that means maximum/fastest growth at those temps.

 

[Northern_Brewer]

Maybe. But take a look at the ethanol production vs temp in this doc.
https://www.lallemandbds.com/wp-content/uploads/2013/06/LBDSMascoma_ThermostabilityDocument.pdfPeaks at 95F.

Bioethanol yeast are not terribly representative, they're quite specialist - and Mascoma yeasts even more so!

I believe that. But I'm not sure that means maximum/fastest growth at those temps.

Trust me, we're quite motivated to optimise growth, and that's what works for the strains we use. That's not to say some other strains may not have different optima - but most "normal" cerevisiae are in that kind of range.