Starter with old s-04

[kh54s10]

I advise against making starters with dry yeast. It is not needed and it is cheaper to pitch 2 packs if necessary for cell counts.

But, I had a pack of yeast with the date of 07/2016 that I wanted to use up so I rehydrated while boiling a starter wort. When I got the wort done I looked at the cup with the rehydrating yeast and it had a healthy looking foam.

I proceeded with the starter and it showed signs of working in less than 1/2 hour.

I wonder how much viability the yeast really had remaining. The calculators say not much.

Well I am sure I will have good yeast when I pitch. I made a 2 liter starter and the beer it will be going into will be about 1.059 for 5 gallons.

I probably should just have gotten new yeast, but I am sometimes crazy frugal. And I didn't feel like the trip to the LHBS.

 

[Pkrd]

I think the viability decreases by only 5% per year if stored correctly. So it lasts pretty much forever.

 

[RM-MN]

I advise against making starters with dry yeast. It is not needed and it is cheaper to pitch 2 packs if necessary for cell counts.

But, I had a pack of yeast with the date of 07/2016 that I wanted to use up so I rehydrated while boiling a starter wort. When I got the wort done I looked at the cup with the rehydrating yeast and it had a healthy looking foam.

I proceeded with the starter and it showed signs of working in less than 1/2 hour.

I wonder how much viability the yeast really had remaining. The calculators say not much.

Well I am sure I will have good yeast when I pitch. I made a 2 liter starter and the beer it will be going into will be about 1.059 for 5 gallons.

I probably should just have gotten new yeast, but I am sometimes crazy frugal. And I didn't feel like the trip to the LHBS.

Does this shake your belief in the yeast calculators? Stored correctly, yeast does not commit suicide and dry yeast is about as hardy as anything.

 

[kh54s10]

Does this shake your belief in the yeast calculators? Stored correctly, yeast does not commit suicide and dry yeast is about as hardy as anything.

Not really. I got good foaming with the rehydration, but they yeast is about 2 years old. No idea how many viable cells in there. I did expect action on the starter, it was just quicker than anticipated. I still didn't want to pitch what may have been a tiny amount of viable yeast.

A calculator gives a better idea that just guessing.

Of course if you are not concerned with pitching the proper amount of healthy yeast cells, you could stir the wort with you magic fermentation stick like the earliest brewers did.

 

[kh54s10]

I think the viability decreases by only 5% per year if stored correctly. So it lasts pretty much forever.

I've heard much higher numbers. I don't have the equipment to find out.

 

[RM-MN]

Not really. I got good foaming with the rehydration, but they yeast is about 2 years old. No idea how many viable cells in there. I did expect action on the starter, it was just quicker than anticipated. I still didn't want to pitch what may have been a tiny amount of viable yeast.

A calculator gives a better idea that just guessing.

Of course if you are not concerned with pitching the proper amount of healthy yeast cells, you could stir the wort with you magic fermentation stick like the earliest brewers did.

Not always. Calculators are just an approximation that can be based on bad data. Bad data in, garbage out. Different calculators show different results. They can't all be right. Yeast counts are another area that you should study. I've seen pictures of the yeast plates in the microscope and knowing how far these counts are extrapolated makes me want to scream when I hear about this package of yeast containing 200 billion cells.

 

[Pkrd]

I don't have the equipment to find out.

You can make beer can’t you?

 

[IslandLizard]

Yup, dry yeasts last a long time, especially when refrigerated. When frozen, almost indefinitely.

I've used dry yeast (US-05) that was over 7 years old, and always stored in the freezer at -14 - 0°F (depending on freezer used during the various periods).
When rehydrating it started to develop that thin layer of foam as usual, and the beer krausened and fermented as expected from a fresh pack.

I found half a brick of dry bread yeast that was at least 4 years past the exp. date in the freezer. Worked just as well as yeast from a fresh brick, I compared.

That said, I have a sachet of Belle Saison that came with some equipment... It had never been refrigerated before I got it. It's from 2013. I'm gonna give it a try someday. For science.

 

[kh54s10]

I've heard much higher numbers. I don't have the equipment to find out.

You can make beer can’t you?

I don't know what you mean by this. I can make beer, yes. But how does that tell me how many viable cells are in a 2 year old pack of dry yeast?

 

[kh54s10]

Yup, dry yeasts last a long time, especially when refrigerated. When frozen, almost indefinitely.

I've used dry yeast (US-05) that was over 7 years old, and always stored in the freezer at -14 - 0°F (depending on freezer used during the various periods).
When rehydrating it started to develop that thin layer of foam as usual, and the beer krausened and fermented as expected from a fresh pack.

I found half a brick of dry bread yeast that was at least 4 years past the exp. date in the freezer. Worked just as well as yeast from a fresh brick, I compared.

That said, I have a sachet of Belle Saison that came with some equipment... It had never been refrigerated before I got it. It's from 2013. I'm gonna give it a try someday. For science.

I realize that dry yeast lasts a long time. But I prefer to pitch the proper amount of healthy yeast. One pack of dry yeast is pushing the issue to begin with. On top of that my yeast was 2 years old. I had it out of a refrigerator for 5 days last fall due to a move. So in addition to it being old, it's handling was a bit in question.

Yes you can inoculate a wort with only a few cells of yeast, or even just let it wild ferment and you will get beer. But you have little clue as to what the finished beer will be like and that is not the way I want to go.

I think I did overestimate the loss due to time but I think my process was better than just going for it!

It is very happily fermenting as we speak.

 

[IslandLizard]

I realize that dry yeast lasts a long time. But I prefer to pitch the proper amount of healthy yeast. One pack of dry yeast is pushing the issue to begin with. On top of that my yeast was 2 years old. I had it out of a refrigerator for 5 days last fall due to a move. So in addition to it being old, it's handling was a bit in question.

Yes you can inoculate a wort with only a few cells of yeast, or even just let it wild ferment and you will get beer. But you have little clue as to what the finished beer will be like and that is not the way I want to go.

I think I did overestimate the loss due to time but I think my process was better than just going for it!

It is very happily fermenting as we speak.

Mr. Malty gives me 46% viability after 2 years for dry yeast, I guess that's refrigerated?

You did the right thing to make a starter, better than pitching as is. There will always be growth, and renewal of cells is key.

Dry yeast is a lot more resilient than liquid, so having it out of the fridge for a few days (or weeks) won't harm it much at all. Dry yeast is in an extremely dormant state. But as soon as it gets damp it needs nourishment pronto.