Washed yeast shelf life and Dry hopped washing

2 questions. I'm about to find out, but wanted to get a few opinions in the event I could be wasting my time. I've got some washed 3068 leftover from last June? that i made last summer Hefe's with, it's been hibernating in my fridge ever since. Think it's still good? I'm going to give it some wort and see how it goes.

Also, I've been just pitching pellets into my boil these days, leaving alot of hop particles in my trub at the bottom of my fermenters. I just washed some 05 last night using that same hop laden trub, I'd even dry hopped this IPA. Any issues with this?

The very general answer to question 1 is that there is likely some yeast still alive in that 8 month old culture and it will probably get going again in a new starter. If you add the whole thing to your starter, you will probably end up pitching a lot of dead cells also. It will likely still make beer for you. Same with question 2, it will probably still make beer for you, especially since you should have washed most of the hop trub off the good yeast.

The technical answer is that the yeast (in both cases) will not be as healthy as it could be, and it is best to pitch happy, healthy yeast. Yeast coming from a highly hopped beer will not be very active. Hops have been used for centuries to preserve beer, which certainly also affects the yeast. It is not common practice to reuse yeast from highly hopped or high gravity beers. Have you considered freezing your yeast for long term storage?

What will freezing washed yeast jars do? I have several washed yeast jars, all dated, most under 2 months old.
I know there are a few I won't be using soon. If I freeze them, will the yeast last longer and stay healthier?

The best way to know is to let it ferment a small wort and check some basic fermentation metrics. Estimate 1 billion cells per ml of settled slurry. (A microscope would give you a much better idea). Pitch it a little heavy. Check how fast it starts, attenuation and flocculation. Give it a smell as well.
Many people, including me, have seen mo problems with old slurries. Others toss it after a few weeks to a month.

kkimmes said:

What will freezing washed yeast jars do? I have several washed yeast jars, all dated, most under 2 months old.
I know there are a few I won't be using soon. If I freeze them, will the yeast last longer and stay healthier?

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Check out the thread in the yeast forum on freezing yeast. Short answer is that you can't just stick them in the freezer, unfortunately.

kkimmes said:

What will freezing washed yeast jars do? I have several washed yeast jars, all dated, most under 2 months old.
I know there are a few I won't be using soon. If I freeze them, will the yeast last longer and stay healthier?

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Freezing yeast without glycerin will kill it.

Hey Woodland, I'm curious if adding a bit of yeast nutrient into my wash water as I boil and sanitize it would effect the health & happiness of my washed & stored yeasts? Any thoughts on this?
I haven't really searched this out on the forum too deeply, i know most people just boil water and use just that...

Thoughts or experience anyone?

crushingblackdoom said:

Hey Woodland, I'm curious if adding a bit of yeast nutrient into my wash water as I boil and sanitize it would effect the health & happiness of my washed & stored yeasts? Any thoughts on this?
I haven't really searched this out on the forum too deeply, i know most people just boil water and use just that...

Thoughts or experience anyone?

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What works for me is just pouring the yeast slurry post fermentation into jars and putting it in the fridge. Simple. Easy. Works.

http://woodlandbrew.blogspot.com/2013/01/yeast-storage.html

One theory that I have heard is that yeast will try to adapt to any environment that they are in. If there are any nutrients available they will try to consume it. With yeast-rinsing (aka water washing) the water is boiled to remove to oxygen and the yeast is rinsed several times to remove a vast majority of nutrients from the brine. If the environment is devoid of nutrients the yeast will stay in a rest state and not try to reproduce. Reproduction under stressed conditions leads to mutations.

So from that respect it's probably better not to add yeast nutrients to stored yeast.

What will help is allowing them to build their reserves. That means they should be coming out of a normal fermentation that has been allowed to run to completion. This will rebuild the glycogen reserves.

You can see this effect on some experiments I ran recently:
http://woodlandbrew.blogspot.com/2013/02/side-by-side-starters-3-of-4.html

I've got some washed and not washed yeast sitting in my fridge waiting to see what effects storage might have on the yeast. (And more importantly how that yeast effects the beer) But, so far I'm happy with how my beer is turning out with just dumping the yeast cake, trub and all, into jars.

Dude. Thanx a mil, Woodland, for the simple & concise response. I've learned so much from this forum! Thanx for the K.I.S.S. advice, mang.

crushingblackdoom said:

Dude. Thanx a mil, Woodland, for the simple & concise response. I've learned so much from this forum! Thanx for the K.I.S.S. advice, mang.

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Thanks, just saying what I know.

Interesting Woodland. Your method is much easier, no questions. Thee are many circumstance that require a wash, though. As an example. My Hop laden trub that's commingling with my yeasties needs washed out for use in my upcoming american wheat. It may not have much effect on flavor/taste, but why risk it. You can always use your method, wash it if need be, and make a starter with relative ease.

I agree that from a set hopped IPA to a light American Lager there may be some flavor carry over. Washing to remove the trub just to remove it can be counter productive.

I cleaned out my cold storage area where I keep harvested (Rinsed - 2nd generation) and I found a couple of pint jars of WLP 545 that were 2 years old. They looked fine (no obvious signs of funkiness) but I thought for sure they would be long dead. But I just had to see if there was anything left alive so I dropped them into a flask with boiled /cooled extract, corked it and waited. It took two days but amazingly they are chugging along. I thought maybe there was something wild going on but the smell coming off is clean and tasty.

Just goes to show the resilience of our little friends.

Has anyone else done something like this with yeast cells that were not frozen?

I've used a jar of 6 month old yeast with no problems at all.

WoodlandBrew said:

What works for me is just pouring the yeast slurry post fermentation into jars and putting it in the fridge. Simple. Easy. Works.

http://woodlandbrew.blogspot.com/2013/01/yeast-storage.html

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Interesting read, thanks WoodlandBrew.


If I understand the article, 1 quart has estimated 1 trillion cells at 90% viability. So in theory for my lagers, I could directly pitch 1/2 quart of 6 month old yeast into 5 gallons of lager without need of making a starter. Is that correct?

Sorry OP for the hijack.

02fx4dude said:

Interesting read, thanks WoodlandBrew.


If I understand the article, 1 quart has estimated 1 trillion cells at 90% viability. So in theory for my lagers, I could directly pitch 1/2 quart of 6 month old yeast into 5 gallons of lager without need of making a starter. Is that correct?

Sorry OP for the hijack.

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That sounds about right. It might take a little longer to get going as the glycogen reserves will be low. Another way to estimate cell count is by volume. 1 ml of thick settled slurry is about 2 billion cells. (I often use 1 billion as a safe estimate)