Old yeasties

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sparkyaber

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I thought I read some where that harvested yeast looses 25% viability every month. If that is the case, after 4 months what would be left?
The reason I ask is I had 3 pint jars of 1028 Wyeast in my very cold fridge (34-38 degrees F) that I harvested back at the end of June. I guess I have a 2 questions now. The first being, how much yeast is in one of those jars? Most of my jars have between 1/4" and 3/8" of yeast at the bottom.
As for the second question, So yesterday I whipped up a 2 liter starter, and dumped all 3 jars in. I did warm the jars up in a warm water bath, decanted the water off the little cakes. Now I know some of you never see any "activity" in your starters but I always have, maybe just the smallest bubbles being formed, a smell of alcohol, something. This morning I awoke to find the stir bar had been thrown, and it really did not look like the normal yeasties on the bottom, it was more gray then off white. It has only been about 18 hours, so this may be a little premature, but I want to brew this weekend, and need to make a starter for this brew.

"Did I ruin my starter?"
Sorry couldn't resist.;)
I know many of you have used older yeast, but you may have taken better care of those little guys.
Thanks for the input.
 
Yeast is hardier than most give credit for. I have used 2 year old harvested yeast with no problems. I don't even use a stirplate. I do starters in gallon arizona tea jugs and shake the hell out of them every so often. I leave the lid closed until the jug looks like it is going to explode (there is my proof of life) and then leave it loosely until done. I do, however, make large starters several days before brew day just in case. I also decant all of the starter wort possible before pitching.
 
Alright, now I am totally confused. I figured I would take a hydrometer reading to see if the yeast has started to ferment out. Well, I drew a sample and it read 1.070!!
Now I used 2 liters, 8 cups, 2 quarts, 1/2 gallon, what ever measurement you want, plus 2 cups dme, 2 tsp yeast nutrient.
So, one, the yeast has had 24 hours to go, and nothing, and two, how the heck did I get such a high gravity?
Palmer says 1 pint (470 ml) of water with 1/2 cup dme, gives you about 1.040, right, did I mess up a conversion some where?
take the above and times 4 right?
I am so lost.
 
hmmm odd if your measurements are accurate you should of had a slightly lower gravity. you should of multiplied by 4.23 ... but 4 is close enough. are you sure you measured the gravity correctly and adjusted it for temp?

anyway the "old" yeast should be ok. yeast can survive millions of years and still be viable.
 
Bobby M recently did a test on year old stored yeast here; https://www.homebrewtalk.com/f13/testing-limits-yeast-viability-126707/

And my LHBS cells outdated tubes and packs of yeast dirt cheap 2-3 dollars each and I usually grab a couple tubes of belgian or other interesting yeast when I am there and shove it in my fridge. and I have never had a problem with one of those tubes. I usually make a starter but I once pitched a year old tube of Belgian High Gravity yeast directly into a 2.5 gallon batch of a Belgian Dark Strong, and after about 4 days it took off beautifully.

You just need first to apply the "sniff test" if it smell bad, especially if it smells like week old gorilla poop in a diaper left on the side of the road in the heat of summer.

Then make a starter, and if it takes off you are fine. The purpose of a starter is to reproduce any viable cells in a batch of yeast....that;s how we can grow a starter form the dregs in a bottle of beer incrementally...and that beer may be months old.

Even if you have a few still living cells, you can grow them....That's how we can harvest a huge starter (incrementally) from the dregs in a bottle of some commercial beers. You take those few living cells and grow them into more.

If yeast can be grown from a tiny amount that has been encased in amber for 45 million years, 45 million year old yeast ferments amber ale we really don't need to sweat too much about yeast viability....we just make starters.

And as to "activity" the only activity you need to concern yourself with is the band of yeast at the bottom of the flask.....anything else (except for hydro readings) may or may not occur, so shouldn't be used as "gospel" as a sign of fermentation. Krausens or airlcok bubbles are not reliable indicators, because they don't always occur for everybody, or for every fermentation, so that is less reliable.
 
Well, thanks for the help guys, but I checked on the starter this morning, and still, the gravity has not moved 1.070. This part is bothering me, I have never needed to take a gravity reading on a starter before, so I am curious as to what I have been using/making all along. My basement is a nice 62 degrees, so I am assuming with no fermentation, the starter should be close to that.
So this starter is down the drain, I will head to the brew store today and get some new stuff. I can't wait for this stuff to take off.
 
Oh, one more thing on the gravity. I know it was enough water, with none lost to boiling, because that 1 gallon jug was almost exactly half full. I checked and double checked that reading this morning, and it did not change.
 
You mean you dumped a starter because 24 hours later it hadn't taken off???? Haven't you ever heard of lag time? We say over that https://www.homebrewtalk.com/f39/fermentation-can-take-24-72-hrs-show-visible-signs-43635/

Although starters usually go faster than that, that doesn't necesarily menn it wouldn't take 24-48 hours for a starter to take off.

The yeast often has to come out of a dormant period, then when it find it self surrounded by 5 gallons of food, before it starts truly diving in the yeastit has start growing an army to best eat it, so they have a wild orgy and then make a bunch of yeast babies. Then they get to work.

So that is why it can take a few days before the really get going..the first part of it is called lag time, the waking up part, lag time, then the sex part is obviously called the reproductive phase....

Especially as you mentioned that you were using older yeast, you have to give those viable cells enough time to reproduce new viable cells.!!! That takes time.

If anything I would have brought your starter upstairs to where it was warmer than 62 degrees, that to me is more of a reason for your sluggish yeast activity, the cooler the temps the slower it takes the yeast to get going.

Next time don't rush to dump...even if you decide to go with fresh yeast, feed this starter a couple times and jar it...for one thing you will know that your yeast is hardier than you think it is, and you would have gone "oh, I guess I didn't need to dump it any way, I just needed patience.

Then next time you won't worry about your starter so much.
 
It had been almost 48 hours 46 to be exact, with nothing, maybe I should have waited longer, but I need that jug to start a starter that will be good to go on Monday, now I am pushing that. I would have left it if I had something else to make a starter in, or at least looked for something else.
Revvy, thanks, you comments make perfect sense.
 
but there was other things you could of tried first. moving to warmer temps (upper 60s), adding yeast nutrient and energizer, added more yeast, added more water to lower the gravity.

just curious whats the hurry?
 
but there was other things you could of tried first. moving to warmer temps (upper 60s), adding yeast nutrient and energizer, added more yeast, added more water to lower the gravity.

just curious whats the hurry?

I am a temporary stay at home dad, (lost my job a while back) and my wife has mondays off, so it is a nice brew day since I have my 1 and a 1/2 year old son running around and trying to "help" me all of the time. Next weeks are all busy. Rifle hunting starts in a few weeks, and I still want to bow hunt a few times before that. I think I am busier now than when I was working.
 
You want your starter gravity to be closer to 1.030 anyway, not 1.070. That high of a gravity is going to stress the yeast.

I know this, that is why I am a little peaved right now, I am sure I used the right amounts of water and DME, I even had the measuring cup with the dme still stuck to it. 2 cups dme- 1/2 gallon water. should have been around 1.040.
 
I think that 100 grams= about 1 cup, so if you say 1.030, 100 grams per liter, should be 1.040.
Hey, I just followed Palmers lead- Page 73 How to Brew, he says " one pint water, one half cup dme" for a starter. This is a starter about 1.040. I will try to weight it next time.
 
+1 always by weight... measuring by volume is too variable. I remember the saying '100g per Liter' which is about 1.046, so I go with 80-90g per liter which is close enough for gub'ment work. :D
 
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