Pitching Slurry

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Nubiwan

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Was hoping to pitch some 5-6 month old slurry. Got about 6 mason jars from 2 previous batches of US-05 and Saf-23.

Can I just get the slurry to pitching temp, decant the liquid off, and pitch? Depending who you read / believe, this will and will not work. On the other hand, making a starter sounds a lot like making beer before a beer.

What is the best way to make a starter for slurry? You have to use DME, and how much would be required? Hate to be ignorant, any other form of fermentable usable? Honey? Syrop? Don't happen to have any DME Handy.
 

Brewdog80

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5 to 6 months old? if no starter, and yeast has been in fridge, it will be a while waking them up. I have a half dozen pints of wort I made and canned from older dme. I use that as starter. But just warming up your yeast to pitching temp, should work.....
 

VikeMan

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You could pitch a lot of the slurry and hope for the best. But you really don't know how many viable cells you have or their overall health.

I would take a small amount of the slurry and make a starter, to be more sure. How big a starter would depend on the batch size and gravity of the beer you are going to make. There are plenty of calculators out there to help with this. Here's one: Yeast Pitch Rate and Starter Calculator - Brewer's Friend

And no, making a starter with mostly simple sugars isn't a good idea, because the yeast won't have to gear up to use more complex sugars like they will in the main batch, and because honey, syrups, etc. are terrible nutrient-wise.
 

eric19312

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That is a lot older than I'd be comfortable pitching and I do re-pitch US-05 a lot, but mostly with slurry either 1, 2 or 3 weeks old.

Beersmith assumes slurry loses 50% of viability every month so it would calculate your slurry is now about 5% viable. 5 gallons of 1.056 OG ale would need 1.9 liters of slurry. 5 gallons of 1.044 lager would need 3 liters of this slurry. But even if you had that much slurry in your mason jars would you really want to add 2-3 liters of dead yeast and trub to your beer? Maybe it will be ok but it doesn't seem worth it to me.

Beersmith may be conservative. Even if it loses viability at same rate as commercial yeast you are going to be at about 25% viability. Still even there you need a lot of yeast and you are putting a lot of crap into your beer.

You could build these yeasts back up with a starter but that will take a few days and these are not expensive or rare yeasts. The DME to build the starters may cost as much as just buying new packets. The proper ratio of DME to starter wort is 10% by weight. Use 100 grams of DME and enough water to make 1 liter of starter wort. This free calculator will walk you through it:
 

eric19312

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Reading the thread sounds like you are anxious to get brewing and don't want to wait for either DME or new yeast.

Your mention of making a beer to make a beer might not be worst idea. Make a 1 gallon all grain batch as a mini mash on stove top or oven. Boil a few minutes to sanitize, no hops or just a pellet or two if you have some open. Aim for a weak wort, not higher than 1.040, might need something like 1.5 pounds of malted grain. Now you have starter wort without having to go to the store to get DME.
 

Alan Reginato

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Check the comments. 5 months old.

From a blog about Kveik, taste the liquid part of slurry, if it's ok, like not sour or disgusting, you should be good to go.
 
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Nubiwan

Nubiwan

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I do have the US 05 in a packet of dry yeast. I just hoped I could use the slurry. Appears not. Conliftin responses on here. Seem to recall a thread someone pitched old slurry
Check the comments. 5 months old.

From a blog about Kveik, taste the liquid part of slurry, if it's ok, like not sour or disgusting, you should be good to go.
I read that earlier. Its the time preparing starter that will rule this out for me. I want to just chuck the slurry in the batch and wait and see what happens. Clearly, this seems to be inadvisable.
 

CascadesBrewer

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Check the comments. 5 months old.
I am not sure I would be comfortable with zero visible activity after 5 days.

I do have the US 05 in a packet of dry yeast.
If I had a fresh pack of US-05, I would not even think about risking a batch of beer just to save $4.

Personally, I find that direct pitching harvested slurry takes off pretty decent if it was harvested 4 to 6 weeks prior. Beyond that, I have had some sluggish starts, so I will be sure to make a starter. At around the 4 month stage I will either dump the yeast or will use some of the slurry in a 1L starter, then save off the yeast slurry.
 

Oleson M.D.

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Yes, do the aroma test, and the taste test. If that goes well, then make a starter. You will be glad you did.

5 months is the max time for storage for us. We try to use a fresh slurry within 2 to 4 weeks.
 
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Just last week I "woke up" a jar of Wyeast London Ale #1028 that had been in the back of the fridge for 8 months. Made a starter, tossed in the slurry, and sat back. I figured what the heck, if it doesn't work I'll get a new tube. Took longer than usual, but it krausened after abut 30 hours. I dumped the starter into my 3g batch of porter and whammo!, the lag time was maybe 6 hours for the airlock to go to full bubble.

It's a great feeling bringing a jar full of old cells back to life.
 
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hottpeper13

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When I'm in that situation I make a vitality starter.
1- Take yeast out of fridge on brew day morning
2- Sanitize a 1 qt jar
3- Fill jar with wort after 10 min of boiling and cover with foil
4- Place jar in freezer

By the time your done with chilling and letting it settle the wort in freezer is ready to pitch on saved cake(sometimes you don't need all the cake)
I pitch the starter and set it next to the fermenter to be at same temp ,then I pitch a very active starter into the fermenter in the morning.
I've never had more then a 4 hr lag time doing this.

I DON'T NEED NO STINKING DME!
 

marc1

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Was hoping to pitch some 5-6 month old slurry. Got about 6 mason jars from 2 previous batches of US-05 and Saf-23.

Can I just get the slurry to pitching temp, decant the liquid off, and pitch? Depending who you read / believe, this will and will not work. On the other hand, making a starter sounds a lot like making beer before a beer.

What is the best way to make a starter for slurry? You have to use DME, and how much would be required? Hate to be ignorant, any other form of fermentable usable? Honey? Syrop? Don't happen to have any DME Handy.
You don't have to use DME, you could use grain to make wort as well. Make a small 0.75 to 1 gallon batch around 1.038 to 1.040 and use that. Use a quart to wake it up then the rest to build it up.
 
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Nubiwan

Nubiwan

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You don't have to use DME, you could use grain to make wort as well. Make a small 0.75 to 1 gallon batch around 1.038 to 1.040 and use that. Use a quart to wake it up then the rest to build it up.
Yeah, my thinking that exactly. I assume you to this to make sure you get some form of krausen / viability. Yes?

How long do you leave it? How much Slurry do I add to this?
 

odie

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just pitch it. Open the mason jar and take a sniff. If is smells ok it probably is. Decant the beer on top, pour in a little fresh wort and swirl it up and pitch. No starter needed. I've used many fermenter yeast slurries that have been sitting in the fridge for months.

But all my wort gets filtered so my fermenter cake is all yeast, no trub.
 

marc1

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Yeah, my thinking that exactly. I assume you to this to make sure you get some form of krausen / viability. Yes?

How long do you leave it? How much Slurry do I add to this?
I overbuild starters and save them under beer in mason jars in the fridge. If I don't use it, I'll rebuild it every 6 months to a year. If it's been a while, I'll make the small starter first, give it a day or so on the stirplate, another day on the counter, then a few days in the fridge to crash it out. Then decant and repeat with the larger volume. Pour off a pint for future use, then crash and decant the rest before pitching.
 

eric19312

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While I don't use slurry as old as @odie I have to agree that my process with slurry is to decant and pitch. Since my yeast is usually very very fresh I don't use all that I harvested...seems like estimate is normally about 400mL for a 17.5 gallon batch of 1.060 wort.

If was going to go to the trouble of making a starter I'd just use new yeast. With new liquid yeast I'd build a proper starter. Since I generally use dry yeast when using new yeast I just use enough packets for the batch.

My batch size makes starters kind of difficult. My last batch of ale needed nearly 800 billion cells. You just can't get there without multistep starters even with a 5 liter flask. Thats a lot of DME.
 

Oleson M.D.

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Regarding Diamond Lager, and a harvested slurry...

Just pitched 2 qts into 11 gallons of wort. The slurry was in a gallon glass jug, and was harvested ten days ago.

I decided to "feed it" with some sterile wort (big mistake). The bottle was shaken up, and left to sit for a few minutes on the counter. Shook it again a few minutes later, and I had a full blown volcano on my hands. Yeast was bubbling out of the bottle under pressure. A more accurate description is the yeast was spraying out of the bottle. Had to immediately pitch the yeast as it was out of control.

This is probably the 10th or maybe 12th generation. I have lost track.
 

VikeMan

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Just pitched 2 qts into 11 gallons of wort. The slurry was in a gallon glass jug, and was harvested ten days ago.
2 quarts of slurry, assuming it was truly slurry (i.e. mostly yeast), is a massive overpitch for 11 gallons of wort. Was this some sort of experiment?
 

Oleson M.D.

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Ha! Every time we brew it is an experiment. Yes, we over pitch each brew. Works for us.
This was a German Pils.
 

Bassman2003

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Yeast re-pitching is a very interesting part of brewing imho. It is a great practice but it reinforces the need to "brew clean" meaning to put trub free wort in your fermenter so your yeast slurry can be mainly yeast. It is best to store the yeast with some fresh wort that it can slowly munch on while the weeks go by.

To answer the OP's view of "starters are like making beer before making beer..." Think of it like creating new healthy yeast cells that can gang up on your batch of beer. Otherwise, the small number of cells will get tired and depleted with so much work to do in a large batch. Wort is just the best medium to grow the yeast and it happens to also be the medium for making beer.
 

madscientist451

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Yeast re-pitching is a very interesting part of brewing imho. It is a great practice but it reinforces the need to "brew clean" meaning to put trub free wort in your fermenter so your yeast slurry can be mainly yeast. It is best to store the yeast with some fresh wort that it can slowly munch on while the weeks go by.
Its even better to make an extra large starter and pitch half and save half for your yeast bank. No need to fuss over "trub free" wort, or having hops or other stuff in the yeast you want to save.
I always store my yeast with the fermented DME wort that ends up at the top of the jar. I don't want my yeast munching on anything once I put the lid on and place it in the 'fridge.
'
 

Gusso

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I have an almost year old Hornindal in the fridge. I forgot about it but I'm pretty confident it's ready for the challenge.
 

Bassman2003

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Its even better to make an extra large starter and pitch half and save half for your yeast bank. No need to fuss over "trub free" wort, or having hops or other stuff in the yeast you want to save.
I always store my yeast with the fermented DME wort that ends up at the top of the jar. I don't want my yeast munching on anything once I put the lid on and place it in the 'fridge.
'
The 'half the starter each time approach' is a good one. I agree, it takes the pressure off the wort clarity. But why don't you want the yeast to have some food for the long storage period? Without it they will shut down. I think you want them to be in a low, slow state of activity until you ramp them up.
 

madscientist451

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When the yeast are active and stored in a jar, pressure will build up. I learned the downside of this the hard way when I unscrewed the lid and had yeast slurry all over everything in the kitchen in about 8' diameter circle. So now I let the starter quit fermenting and then store it. I haven't had any issues re-starting the yeast after long storage.
 

Bassman2003

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I am speaking of splitting the difference. When you capture your slurry, putting it in the cold fridge will lower the temps and overall yeast activity. Since the yeast will be sluggish, they will not eat very much, but they will still eat some. You will not be able to completely seal the container, but the yeast will not be starved and go into total hibernation.

I am not speaking of issues, but optimal conditions for longer storage times.
 

seatazzz

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I'm a huge proponent of using yeast slurry; it's cheap, it works, and as long as your sanitation is on point, and you keep it in the fridge, will last a long time. I've had a few mishaps, particularly with 34/70; it doesn't seem to like going beyond 3 generations, but that may just be something I did wrong. I've got about half a jar of Imperial Loki slurry in my fridge that I've used a small amount of several times now for different beers; each of them turned out fine. And since I'm a solid member of the WF Lager club, I do the same with my lager yeasts; the first pitch with fresh yeast makes a meh lager, but subsequent brews with the slurry are spectacular; perhaps because overpitching? Dunno for sure. I've even re-used slurry from a WF lager in a more traditional cold-fermented one, and vice versa; and they were just fine.

I don't even let it warm up anymore; straight from the fridge into the chilled wort it goes. As someone above said, as long as the beer on top smells and tastes fine, you're golden.
 
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