Some pointers on yeast (harvesting and health in general)

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lindormonster

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Wondering if anyone has any pointers for this (bare with me)

I have a strain of Kveik that I like using and harvested the slurry from a batch - added cooled boiled water to the empty bucket, swirled up and then decanted to mason jars which were kept in the fridge. I gave one jar to my dad and kept the other for myself and have been using it for some time now (possibly 2+ years) for brews on and off - same with dad who has used on multiple 5 ish % beers over the past few months.

This was virgin yeast when I did this and had only been used on the one batch which was around 8% abv

These brews are all 10% and over beers and the yeast has munched through it with no problem for all this time - Normally in 4 or 5 days max I have done loads of batches with it and it never stalled or had any issues

I would normally pitch one heaped teaspoon of slurry from the bottom of the jar but on the last four or so I have given it a heaped dessert spoons worth

How ever the last two brews I have done the fermentation has taken off fast and well then stalled out about 20 points higher than what it is supposed to

The first one I bottled and there were no bottle bombs or any over carbonation - the beer is fine and has been aging nicely for a few months now (apart from the ones I have drunk already) - Did not notice this until it was in the bottling bucket so a bit late to remidy and I thought it might be a one off it tastes stronger than the 9ish % it says it is

With the knowledge that the above did not finish properly I have been keeping more of an eye on things BUT the same problem has arisen again - Stalled out around 20 points too high and showing only around 50% attenuation based on the gravity readings

Brewed 9th april
OG 1.120 (which was spot on where it was supposed to be)
Temp settings were
Day 1 - 18c
Day 3 - 20c
Day 6 - 22c
Day 9 - 24c

Its still at 24c - thats temp inside of fermenter - i have in a temp controlled fridge with heater in there

was showing activity still last monday but it still and flat now - Gravity reading yesterday was 1.056 it should be at 1.035 (11.45%) where as its around 8.4%

Mash temp and everything else was spot on and nothing went wrong in the brewing process infact it wasd spot on perfect at all stages

I have had this same yeast up to 12.6% with no issues so I dont think im pushing it too much

Gravity readings taken using hydrometer


To remidy I am going to make up a started today with some DME and some more of the Kveik yeast and pitch at high krausen with a hope it will eat through the last bit - Not really keen to introduce champagne yeast or another type of yeast to the beer as I am working on this recipie and will be using the kveik again


Onto questions

1 - does anyone think im missing something here - I am guessing the yeast is far too old now hence the issue

2 - Have i just been underpitching? as I mentioned above no problem on previous brews and I have actually increased amount pitched

3 - Moving forward:

I want to keep using this yeast and am wondering if I can buy some more (Liquid pouch), Make a batch of 5% ABV DME solution and ferment them wash as I did above and store OR am i just being a tight arse and should buy a pack for each new brew I do ? I am happy to keep buying but it was so much more handy to have a jar in the fridge as I could brew when I wanted rather than having to wait for yeast to arrive - Would love to know what and how other people are doing this with their yeast

I was planning on doing the above and putting in some air tight food grade plastic test tubes which I could keep in the fridge thus meaning i could pull a tube the day before and let heat to room temp then pitch as normal

If the above is not workable im happy to go back to buying for each batch but would just prefer to harvest my own and store in individual portions ready to use

Any help or ideas much appreciated
 
I may be wrong (I frequently am) but two things spring to mind:
  1. The age of your yeast. It’s quite possible that it has been contaminated so it may be time to lash out on a new batch.
  2. My understanding of culturing your own yeast is that it will finish up in three layers. Dead at the bottom (a darker layer), live in the middle (a much lighter layer) and then water in the top. Above you state “I would normally pitch one heaped teaspoon of slurry from the bottom of the jar but on the last four or so I have given it a heaped dessert spoons worth.” So it’s possible you have pitched an increasing amount of dead yeast.
Enjoy!
:hat:
 
Same as Dutto I woud not keep my yeast that long and I do use Kveik I only use it about 3 times max then do a fresh pitch of new Kveik.
Overpitching is easily done with Kveik as it is a monster of a yeast as it works better when stressed is what I have been told.
Infection is a possibility as you open the jar to pitch and airborne yeasts will eventually get in and possibly cause the strain not to be a pure strain. yeast can be kept for long periods but just keeping it in a jar is not recommended. You could dry it and store the flakes which can be stored in containers or it can be frozen again I have not done it myself but other brewers have with success
 
Kveik is very flocculant. If you underpitch over and over from the same yeast slurry, maybe it became even more and now it's decanting before finish fermentation. Or maybe, because underpitch too, it had some mutations and became less attenuative.

Try put all the jar inside and give a swirl on day 5.
 
It's not ideal to be reusing yeast that's being used in 10+% beers, it stresses it and one of the side-effects is that it is more likely to mutate. Better to overbuild a starter and use that rather than yeast from the main beer. AIUI that's one reason why some of the Trappists make their smaller beers - the big ones are the ones that sell, but they don't reuse yeast once it's been used in the quadrupel so they need to build it up in something weaker.

Also single strain yeasts tend to be less stable than a proper multistrain, so that may also be a factor - commercial breweries using liquid yeast from a lab will generally only use it for maybe 8 pitches before starting again, whereas some of the British family breweries have been repitching multistrains for decades.
 
It's not ideal to be reusing yeast that's being used in 10+% beers, it stresses it and one of the side-effects is that it is more likely to mutate. Better to overbuild a starter and use that rather than yeast from the main beer. AIUI that's one reason why some of the Trappists make their smaller beers - the big ones are the ones that sell, but they don't reuse yeast once it's been used in the quadrupel so they need to build it up in something weaker.

Also single strain yeasts tend to be less stable than a proper multistrain, so that may also be a factor - commercial breweries using liquid yeast from a lab will generally only use it for maybe 8 pitches before starting again, whereas some of the British family breweries have been repitching multistrains for decades.
That's what I had understood, too. I can't get hold of a new culture of WLP 072 and mine is now 2 years old and I use it for 10% beers.
It's too late to over build from the original source, but are you saying the trappists make a lighter beer from yeast that has been used in a strong beer and then use the "rested" yeast to make strong beers again.
Or have I musunderstood.?
 
I've tried some of the kveik isolates and didn't much like the beer they produced-except for opshaug- so I'm not an expert on this strain, but I had always thought they needed a decent quantity of additional yeast nutrients. Maybe that's Contributing to why yours is stalling.
 
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I have mainly used Opshaug as well, majority of brews I used first generation dried and frozen flakes. A little while ago I decanted out the good looking layer ( which is easy to spot in the fermentasaurus collection bottle ) into a sterilised pot which I keep in the fridge. Last two brews with this kveik I used a sterilised spoon ( boiled and steamed then starsan ) to remove a teaspoon which I add directly into fermenter whilst the decant is occurring from the kettle.
I do use a double dose of nutrients, I do use oxygen but beers around 5%. The " wet " yeast seems to kick off quicker and goes really fast, picture of current ferment at 30 hours.
Sunday pitched about 1400 into 1041 and in 41 hours it's down to an estimated 1.013 accounting for ispindel vagaries, pressure and krausen . The ferment must be kept warm I aim for more than 29 C but not more than 32 otherwise it stalls and falls and then it's game over really. It doesn't seem to be effected by pressure as it can chug away at 30psi , I found the opshaug not very fruity unless very hot ie over 35 degrees and then I think there are alternatives to try with more expression.
I've never made a starter with kveik although might build one to save a fresher batch in the future.
IMG_20220509_195626.jpg
In summary don't overpitch, pitch it hot, oxygenate and lots of nutrients, keep it warm. Think about a top cropping to restart your yeast reserve or a collection of the good stuff from the bottom of your fermenter. I've often wondered if the aseptic removal of the krausen ring after transfer is worth doing.
 
That's what I had understood, too. I can't get hold of a new culture of WLP 072 and mine is now 2 years old and I use it for 10% beers.
It's too late to over build from the original source, but are you saying the trappists make a lighter beer from yeast that has been used in a strong beer and then use the "rested" yeast to make strong beers again.
Or have I musunderstood.?


If you keep an eye on Yeastman.com, WLP072 does show up sometimes as being available for retailers to buy.

No, once the yeast had been in the strong stuff, it never goes back to weaker beer, they grow it up again from culture (but I suspect not necessarily right from scratch, potentially from a low-ABV "starter" held over from before).

If that's all you've got then that's what you have to work with, some of the damage has been done but if it's still working OK, then it's not too late.
 
My "house" yeast is a BE-134 that fermented a 8% beer in its first generation, in the 4th gen a 4%. Kinda made a good job, but poor yeasts... I don't use extra nutrients, my wort oxygenation is only splash, I ain't got temp control, the slurry is kept at closed beer bottles (last time was nearly normal beer carb) and suvive for 4 to 6 months. So they have to work with what they have.

Still, It made good beer!
 
My "house" yeast is a BE-134 that fermented a 8% beer in its first generation, in the 4th gen a 4%. Kinda made a good job, but poor yeasts... I don't use extra nutrients, my wort oxygenation is only splash, I ain't got temp control, the slurry is kept at closed beer bottles (last time was nearly normal beer carb) and suvive for 4 to 6 months. So they have to work with what they have.

Still, It made good beer!
If it works, it's good.
If that's all you've got then that's what you have to work with, some of the damage has been done but if it's still working OK, then it's not too late.
As NB pointed out, if it's working, it's working. I've still got a few bottles left of 6% and 7% beer I can reculture from if necessary, but this yeast seems quite resilient and it'll be interesting to see how it copes with a second 10%-er. It's chugging along nicely at the moment. The thing is that I only make this strong stuff occasionally as it's my wife who drinks it- too strong for me, I'm a quarts (not quartz) man.
 
Can't blame her for hitting the strong stuff, if she's got to put up with you... :onechug:
Spot on NB. She's so addicted to my Bière du Renard she even laughs at my jokes.
That's how I know she's addicted.!
Hear the one about the lad who had his friends and family in fits when he said he wanted to be a comedian?

Edit.
Good job she doesn't do beer forums. Her political opinions leave mine looking very mild. Which they are, if course.
 
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I've never used Kveik yeast but from a commercial point of view I would never harvest yeast from a 10% beer, anything over 1.040 and the view is that our house yeast will have been overworked and stressed (again i don't have any experience of kveik so just an FYI on that part).

May be worth looking into acid washing before you pitch, this will ensure the yeast you have cropped is as healthy as it can be before you repitch. We take a ph reading then slowly add diluted phosphoric acid until the ph is at exactly 2.1.
 
Do we know which Kveik it is? And is it single or multi strain?
 
I am summising it is Voss as Kveik is usually called Kveik when it is Voss but you all know what happens to people that assume. Maybe better for the OP to answer
 
Just to update as it seems I was barking up completely the wrong tree here:

I also had another beer in the fermentor BUT used champagne yeast on it - This also stalled (after i posted this thread) at around 8.6% (was supposed to be 15%)

So I started to have a bit of a think as obviously something else if a different yeast is stalling as well

First step was I made a starter up with the Kviek slurry which took off fine and was at full krausen in a day - Pitched to the second stalled Kviek beer

No activity or movement for days

Did some research and chanced up something called Amyloglucosidase which I wont bore you with as most of you probably already know what it does BUT I read it can help with stalled fermentation so I bought some and chucked a couple of teaspoons worth into beer number two

Kicked off again and is now sitting at 14.6% (whoops) and is stable at that gravity for over a week (good job we like high abv beer) its very hot but will age it for ever and wait for it to clam down before attempting to drink

No what was the cause of the issue - Well from my notes its down to one thing only.............

Strike water being too hot

The better half used to be in charge of the strike water on brew days and she used to have it bang on perfect. I did these batches on my own and just boiled up the HLT to 100c and got busy not even thinking about it which has obviously been too hot and the sugar has not converted

Thats my guess anyways - After a telling off from the wife she will be back in charge of water temps on the next brew and we will see if the problem is solved

This is also hopefully backed up by the fact the previous beer that was well under in ABV did not explode in the bottles as no fermentable sugar so was not stalled fermentation just too hot strike water ruining the sugar conversion in the mash

Hopefully it is as I really have no clue if its not

Will update after next batch is brewed
 
Without going in to the science the higher the mash temp the higher the beer will finish so may be a contributing factor, the Amyl/Gluco enzyme will make a beer ferment down to dry so that has converted the sugar chains to more easily fermentable hence the re-ferment.
Let us know if it is back to normal on the next brew
 
You have made a brut beer. You will find it will stay dry and might lack body, suggest you carb it a bit higher at least 2.7 vols.
You could back sweeten to put some body in but must use a onto fermentable sugar. Depending on your beer style lactose can work on dark beers.
I used monk fruit extract in a low calorie brut hazy IPA and some people like erythritol ( I have no experience with that).
Doin the most on you tube favour erythritol so could look there for some pointers. If its pale and hoppy or can be made hoppier you might be able to reasign it a brut barley wine.
It may stay like firewater though.
 

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