exspired yeast

[underdogsbrewery]

Hi everybody
Now, if I use an exspired liquid yeast the cells count in the calculator is zero...
Anyway if you active the pack and do a starter it still work.. you know
my doubt isif I do a little starter to wake up the yeast an after go on with the step as the calculator requires how many cells i have to consider for the first step?
There's a rule for it?
Can i look at the "wake up starter" like a new an young yeast pack?

Thank you everybody

 

[GFHomebrew]

Not extremely experienced when it comes to starters here especially starting from hopefully in your case only a few viable cells. But you should get a good idea of your viability of the yeast on your first starter maybe start off with .5 lt or 500 ml spin this for 24 hrs and have a good look at your flask you should see little bubbles rising up through it that's fermentation as you probably know let this go for 3 days is you should see when fermentation is done no more bubbles and definitely no more krausen. Chill this for 24hr or more to drop the yeast this should then give you an idea based on the white slurry at the bottom of the flask once chilled on a saved 500ml starter I'll get about 8mm of slurry. Then bump this up again with let's say 1.5 lt starter or 1 lt depending on your yeast calculator on that 8ml of slurry at bottom of flask I'll put in 50ml of slurry sort of gestimation then spin this for 24hr and she should be ready for the big league in the main party arena you carboy or bucket or whatever you turn your wort into beer with . Good luck and remember give that yeast a smell it should smell creamy or Maybe a little fruity not off or anything if so pitch her in the drain and go get some fresh stuff.

 

[Mark D Pirate]

a single viable cell and patience will get you a decent starter , can try stepping it up a few times .
build a small starter of 500 mls first , let it ferment out , chill and decant spent wort
pitch that yeast after a smell test into a 1000 ml starter , ferment out , chill and decant spent wort
depending on style you may double or triple the starter from there to get a suitable pitch for the OG and temp

 

[underdogsbrewery]

Thanks
I already Did it in the past and everything went well...
But now I was wondering in which way I must use the yeast pitch calculator in this case?
Surely the slurry that I made contents cells alive but how many(more or less obviously, I can't count with accuracy)

 

[Mark D Pirate]

If you've done it before and it worked i'm tempted to call it good luck rather than good practice .

best before and expiry dates assume poor conditions , manufacturer doesn't want to get sued now do they ?
how far out of date was it ?

 

[GFHomebrew]

And always sanitation is critical wild yeast will multiply quicker then the good yeast eventually colonising,your starter if propogating over and over

 

[underdogsbrewery]

1 year next month

 

[Gerry P]

I used a 6 month old smack a couple batches ago that was fine. It was a 2.5 gal. batch so I did a 1 liter starter and stepped it up to 2. If possible you might want to try oxygenating your wort with an aquarium pump or straight O2 when you pitch the yeast. It might help get the ball rolling a little better than shaking.

 

[underdogsbrewery]

Yes I use a stirplate for starter however maybe I have been misunderstood and furthermore my English is not so good.
I opened this discussion becouse I know that the old yeast pack could work but by calculator i have no idea how many cells I'm waking up consequently I have no idea about the size of the starter I need.
If I use yeast pitch calculator since six months old the cells available are zero.
I was wondering if making a 1/2 liter starter i can consider like a new pack and set calculator with a new packaging date or there's no way to know what I'm doing

 

[Gerry P]

I think there are too many variables involved to give you a definitive answer. Companies like Wyeast guarantee at least 100 billion cells, but that doesn't give you an exact number.
The way I see it, like you said above, is to either try to use your old yeast with a starter (I would do at least 2 liters) or buy new yeast. It's best to use a starter with fresher (liquid) yeast as well.
Personally I'd go with the former since it's cheaper. The yeast I mentioned in my last post should have had 0 viable cells, but that was not the case. I think yeast calculator results are not exact tools. Just a hunch here, but they're probably more accurate with fresh yeast than with yeast that's past its prime and therefore should be taken with a grain of salt in situations like yours.

 

[GFHomebrew]

I use an estimated approach to the slurry amount yeast calculator allows your variable yeast amount in mills I store my yeast in a 500ml bottle with increments up the side (thank you homebrew store) you sing these increments I can gauge roughly how much slurry I've got and set this as my initial input into the yeast calculator. So at least spin her up and chill and see if any yeast production.

 

[Mark D Pirate]

I think there are too many variables involved to give you a definitive answer. Companies like Wyeast guarantee at least 100 billion cells, but that doesn't give you an exact number.

Personally I'd go with the former since it's cheaper. The yeast I mentioned in my last post should have had 0 viable cells, but that was not the case. I think yeast calculator results are not exact tools. Just a hunch here, but they're probably more accurate with fresh yeast than with yeast that's past its prime and therefore should be taken with a grain of salt in situations like yours.

the viability would come down to how it was stored surely ? The estimates have been shown to be a bottom threshold , they don't want to get sued

i remember seeing a news feature using 220 yr old yeast from a shipwreck , still made beer !

link here http://www.abc.net.au/catalyst/stories/4481385.htm

 

[underdogsbrewery]

I use an estimated approach to the slurry amount yeast calculator allows your variable yeast amount in mills I store my yeast in a 500ml bottle with increments up the side (thank you homebrew store) you sing these increments I can gauge roughly how much slurry I've got and set this as my initial input into the yeast calculator. So at least spin her up and chill and see if any yeast production.

So if you get from the 500ml starter 100 ml of slurry you should have 100 billion cells available that equals to a new yeast packaged today...
An then you start to make the 'real starter'...
This is as I thought
Moreover on the liquid pack there's a picture that means you can use the yeast without a starter for x liters(WE KNOW WE NEED in any way a starter) and the pack is 125ml
So in case of old packs making 100ml of slurry we could consider like a new yeast pack...
Obviously I'm talking approximately
It's only my opinion... I'm only an amateur

 

[GFHomebrew]

the viability would come down to how it was stored surely ? The estimates have been shown to be a bottom threshold , they don't want to get sued

i remember seeing a news feature using 220 yr old yeast from a shipwreck , still made beer !

link here http://www.abc.net.au/catalyst/stories/4481385.htm

Awesome stuff that there Mark preservation ale aye? Would be cool to have a crack at using some of this yeast bar the brett yeast !

 

[Gerry P]

the viability would come down to how it was stored surely ? The estimates have been shown to be a bottom threshold , they don't want to get sued

i remember seeing a news feature using 220 yr old yeast from a shipwreck , still made beer !

link here http://www.abc.net.au/catalyst/stories/4481385.htm

Yeah, how it was handled, transported, and stored, plus its age would affect the number of viable cells. I'll be honest with y'all, I never even used starters until a couple years ago. I always used Wyeast smack packs and dumped it right in. I had 1 problem over the years, and that was a stuck fermentation in an Imperial stout. I always used fresh yeast though, unlike these days when I might throw a pack/vial of yeast in the fridge and not have a chance to use it for a while. I use a starter with a stir plate now, and since we have access to such high-quality, fresh yeast, I consider starters to be cheap insurance.

 

[Gerry P]

So if you get from the 500ml starter 100 ml of slurry you should have 100 billion cells available that equals to a new yeast packaged today...
An then you start to make the 'real starter'...
This is as I thought
Moreover on the liquid pack there's a picture that means you can use the yeast without a starter for x liters(WE KNOW WE NEED in any way a starter) and the pack is 125ml
So in case of old packs making 100ml of slurry we could consider like a new yeast pack...
Obviously I'm talking approximately
It's only my opinion... I'm only an amateur

Just make a 1 liter starter wort (including yeast nutrient), give that a spin for a day or 2, put it in the fridge for a couple days, dump the stuff that isn't yeast, add 2 liters of new starter wort (including yeast nutrient) to your yeast, give that a spin for a day or 2, fridge for a couple days, done. Make your batch of beer, dump the non-yeast from the flask, swirl a little of your cooled wort around in the flask to loosen it up, dump it in your wort, oxygenate/aerate your wort somehow, then close it up and check regularly for visible yeast activity. If you don't see any, buy new yeast and pitch it, preferably with a starter.
If you like, you can check to see if your gravity dropped at all before pitching new yeast, but I wouldn't bother if I didn't see any bubbles or krausen.