Simple Yeast Storage Procedure

[rhys333]

liquid yeast is a bit costly up here in Canada, if I can get two-four brews from one vial...I am a happy happy camper!

I hear you on that. I pay $11 for a Wyeast pack from the LHBS and $6 for dry yeast like US05.

 

[enkamania]

I hear you on that. I pay $11 for a Wyeast pack from the LHBS and $6 for dry yeast like US05.

Note to self, start yeast smuggling to Canada :rockin:

 

[A50SNAKE]

Note to self, start yeast smuggling to Canada :rockin:

fo show!!!

I pay more, as I live in a small small town, and the shipping is double the price of dry yeast most times...and no lhbs...although, I love OBK Patrick saves me money all the time

 

[rhys333]

fo show!!!

I pay more, as I live in a small small town, and the shipping is double the price of dry yeast most times...and no lhbs...although, I love OBK Patrick saves me money all the time

OBK prices are great. I get nailed on shipping from Ontario to Alberta though. Wish there was a comparable online supplier out west. Hmmm, might be a good opportunity there for someone...

 

[HomeDrewBrew]

OBK prices are great. I get nailed on shipping from Ontario to Alberta though. Wish there was a comparable online supplier out west. Hmmm, might be a good opportunity there for someone...

Check these guys out!
http://www.truenorthbrewsupply.com/

 

[Destovi]

Am I doing this correct? I have the following mason jar of slurry. I use the dump everything to the fermenter approach but use hop bags during the boil. View attachment ImageUploadedByHome Brew1442159825.768381.jpg
I'm guessing this is half a jar of slurry so approximately 237.5 ml. If I assume 1.25B/ml I get just under 300B cells.

Using mr Maltys calculation and my predicted OG of 1.07 (batch size of 5.25G) I think I'd use (0.75 million cells/ml of wort)X(20,000ml of wort)X(17.5 degrees Plato) = 262,500B cells or 215ml of slurry. Now I've had this slurry stored for 2 months so I have to assume 17%/month loss of viability so multiply 262,500 X 34% = 351,750B cells or 280ml of slurry.

Does that all seem correct?

Thanks.

 

[rhys333]

You're in the ballpark there with a slight underpitch, by my rough estimates. If you're in a rush you could go ahead and pitch (you'll be fine), or if you have a day or so make a small starter to refresh the yeast and build a few more cells. I'd be inclined to do the starter in this case, only because you're working with both an underpitch and older yeast. If you do go ahead and just direct pitch, there might be 1 to 2 day lag.

 

[Destovi]

Thanks for the quick reply rhys333. I was mostly referring to my calculations. I have two mason jars filled identically so I'll just use some of the second to make up the difference to ensure I don't underpitch. Thanks again!

 

[brewkinger]

Thanks for the quick reply rhys333. I was mostly referring to my calculations. I have two mason jars filled identically so I'll just use some of the second to make up the difference to ensure I don't underpitch. Thanks again!

I wouldn't bother stealing from that 2nd jar.
WoodlandBrew (OP) has a blog that you should check out.
Some points from his research:
1) 1.5billion cells per mL is a safe bet for most clean slurry.
2) The decrease in viability is not as significant as once thought, so 17% may be incorrect.
3) A 50% underpitch would most likely have no negative effects.

Worth taking a look at what he has researched and found for sure.

 

[Destovi]

Hey brewkinger, thanks for the response as well. I had meant to reply after you posted and I forgot. I've read a lot more from Woodlandbrew since. Thanks!

 

[brewfarmDan]

I have gotten my yeast harvesting proceedure down and thought I would share. I make 10 gallon batches in a SS Conical. 12 to 24 hours after pitch I dump trub thru the bottom valve. 7 to 10 days after pitch I boil 4 mason pint jars and 1 quart jar. My 2000ml flask won't fit in my microwave upright so I set it side ways in a bowl with about 600ml water and boil the water in the MW for several minutes. I cover/lid everything immediately with jars full of boiling water and let cool to room temp. I dump yeast/trub out the bottom valve till it looks like clean yeast, dump all but about 200ml preboiled water from the flask, then dump yeast till I see beer or the flask is full. Give the fask a good swirl then let rest till the trub settles, then dump most of the water from the quart and transfer leaving as much trub behind as possible. Then repeat transfering to the 4 pints about 1/4 full steps.

 

[stever1000]

I haven't had a chance to click through all the pages but I'm a bit confused about using the slurry with a starter...
if i have 400ml of slurry with a bit of beer on top, how do I make a 1.5L starter? Do i add the slurry to 1100ml of starter wort or how do I compensate?
Thanks!

 

[m00ps]

Yeah youd just add as much starter wort as you can with the decanted slurry to make up the final volume

 

[rhys333]

I haven't had a chance to click through all the pages but I'm a bit confused about using the slurry with a starter...
if i have 400ml of slurry with a bit of beer on top, how do I make a 1.5L starter? Do i add the slurry to 1100ml of starter wort or how do I compensate?
Thanks!

You have at least 400 billion cells there already(200B needed for a 5 gal 1.050 beer). Whats the gravity and volume of your beer?

 

[brewkinger]

You have at least 400 billion cells there already(200B needed for a 5 gal 1.050 beer). Whats the gravity and volume of your beer?

Agreed.
And that is a conservative estimate
Depending on how clean the yeast is, you could have 1.5 to 2 times that number.
I would split that in half and just build a small starter if you are making normal beers.

 

[brewkinger]

Double post

 

[stever1000]

The slurry has been in the fridge since february so I was thinking I could pitch more slurry to compensate for yeast that has died since then.
What size of starter should I use instead?

thanks!

 

[rhys333]

The slurry has been in the fridge since february so I was thinking I could pitch more slurry to compensate for yeast that has died since then.
What size of starter should I use instead?

thanks!

I've never stored slurry that long, but others on here have and just direct pitched it. Probably wise to do a starter though. As a wild ass guess maybe its 15-25% viable after 7 months. Could be way higher or lower. Couple suggestions: (1) you could just pitch all of it without a starter in the name of science and see what happens (then tell us), or (2) add some of it to a starter to proof it and build new cells. Perhaps pitch 200ml into a 1.5 L starter (i.e.: 1.5L water + 150g DME).

 

[brewkinger]

I've never stored slurry that long, but others on here have and just direct pitched it. Probably wise to do a starter though. As a wild ass guess maybe its 15-25% viable after 7 months. Could be way higher or lower. Couple suggestions: (1) you could just pitch all of it without a starter in the name of science and see what happens (then tell us), or (2) add some of it to a starter to proof it and build new cells. Perhaps pitch 200ml into a 1.5 L starter (i.e.: 1.5L water + 150g DME).

Exactly what I was thinking.
Woodland Brews blog suggests that viability decay is less than we once thought it to be. I cannot remember the exact number though.
So I concur with the same 2 options above.
I am inclined to lean towards the latter though.
Split it in half and treat each as though they were a single smack pack and then make a 1.5L starter.
(If you are making a normal 1.050-ish beer.)
If it works well then you have a second freebie.
If it does not work then you can still experiment and build the 2nd one up even larger next time.

The downside to pitching the whole 400mL in a single batch is that it may be an overpitch and then you possibly make a bad beer in addition to wasting a perfectly good second opportunity to pitch the 2nd half.

Just my thoughts

 

[christyle]

To me, the downsides of overpitching are minimal and not to be afraid of. I would dump the whole deal into a 2L starter to see what happens, if viable, decant and pitch, then harvest the new, viable yeast for next time rather than continuing to save a partial jar of 7 month old yeast.

 

[peoples22]

First of all, thank all of you guys for all of the expertise and experience you've posted. It has definitely helped me out.

I have a couple of questions (my first yeast harvest today).

1) I just harvested this morning (US 05) after I had my house IPA cold crashing. I left a very small amount of beer in the carboy and then added sterile water from my mason jar, swirled and poured. This picture is about 10 or 15 minutes later, am I looking OK? I dry hopped in the primary in a mesh bag so I expect there to be extra debris.

2) I wanted to brew another IPA today so I was going to run the numbers (need about 300b cells for my pitch) and leave however much slurry I need at room temp to warm up and pitch later on today when the wort is ready. Is this OK or should it refrigerate a day to separate more then decant and pitch?

Thanks!

 

[rhys333]

After settling you'll probably end up with about 180ml compacted slurry, looking at those two smaller jars in your pic. You could use right away if you factor that in, assuming 180 ml slurry at 1.5B cells per ml. Give or take a few cells, one jar will get you that 300B amount.

 

[christyle]

Any reason you added the water? As long as it's viscous enough to pour, you shouldn't need to add any water.

 

[peoples22]

Didn't leave much beer behind to get a good swirl going and I read a few guys adding water instead of using beer due to potential cell loss of higher abv.

Pitched and checked this morning to some nice activity!

 

[tgmartin000]

Ok, so I have a batch of saison I brewed in August. It has been sitting at room temp in primary since then. I'd like to re-use that yeast for a batch of rye saison this weekend. I've heard that keeping the beer on the yeast cake is the best way to keep the yeast.

Given that it's been sitting on beer for about 3 months now, what would the estimated vitality be? My upcoming rye saison is about 1.055 gravity, and I was just going to scoop out about half the cake and pitch the new batch onto the remaining cake. Does that sound about right?

 

[rhys333]

I'm estimating approximately 1.5B cells/ml in fresh slurry with 17% loss in viability per month (or 50% in 3 months). You could try those numbers for calculating amount of slurry needed. Pitching on 1/2 the yeast cake is still an over pitch. It's a good idea to pitch the smaller recommended amounts to ensure fresh cell growth rather than relying entirely on tired old yeast. If you're doing a standard 1.050 5.5 gal brew, you need approximately 200B cells. At an estimated 0.75B cells/ml you'll need only 300 ml of slurry. Add a little more if you want to make sure.

 

[brewkinger]

Ok, so I have a batch of saison I brewed in August. It has been sitting at room temp in primary since then. I'd like to re-use that yeast for a batch of rye saison this weekend. I've heard that keeping the beer on the yeast cake is the best way to keep the yeast.

Given that it's been sitting on beer for about 3 months now, what would the estimated vitality be? My upcoming rye saison is about 1.055 gravity, and I was just going to scoop out about half the cake and pitch the new batch onto the remaining cake. Does that sound about right?

I would not worry too much about viability.
That yeast has barely been asleep for long, so most likely it is still plenty viable enough.
Using Brewers Friend (and assuming 5.5 gallons for a batch volume)
It says 212 Billion cells needed

So I would take a good healthy scoop of 250mL (1 cup) of slurry from the previous batch and chuck it in the new batch.

Assuming a 1B per mL ratio, that gets you plenty to get the job done.
And an even more realistic number of 1.5 Billion cells per mL will get you more than enough to get the job done.

 

[stever1000]

I'm going to attempt to use my 7 month old yeast this week to see what the result of older slurries is.
Since I'm dealing with a large volume of slurry (400ml +) what's the safest way to bring it to room temperature to either pitch into my new wort, or to put in my flask with a small starter for the stir plate?
Should I leave it at room temperature in the morning and use it in the evening when the temperature is close to room temp? I'm worried about shocking the yeast if the temperature isn't close

Thanks!

 

[christyle]

I'm going to attempt to use my 7 month old yeast this week to see what the result of older slurries is.
Since I'm dealing with a large volume of slurry (400ml +) what's the safest way to bring it to room temperature to either pitch into my new wort, or to put in my flask with a small starter for the stir plate?
Should I leave it at room temperature in the morning and use it in the evening when the temperature is close to room temp? I'm worried about shocking the yeast if the temperature isn't close

Thanks!

I take it out of the fridge and let it warm up while I brew. If you're making a starter, I would do the same: Bring it up to temp sitting somewhere warm, then pitch into cooled wort just like you would a beer.

 

[stever1000]

Is there any reason I can't leave it out for 8 hours and then use it in a starter? Or likely will that starve the yeast as they wake up and become active again?