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Yeast harvesting question


tire38

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Hi everyone, things are going well, on batch #11 now. My question is I harvested the yeast from a previous brew and used it(US-05). All went well, harvested from THAT brew yesterday and when I check the jars today there is not the distinctive 3 levels of separation. Only two. I will post a pic later if you like but it's very obvious, 2 levels after 24 hours. Any thoughts?

 

Thanks Ted.

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Yes, you have a nice clean sample and no need to rinse. The third layer is trub - leftover break, hop matter, crap like that. If you were missing the top layer of beer that protects the yeast it can be replaced with boiled water reduced to a pH of 2.2, same as you would if you rinsed it before storage.

 

Otto doesn't have a third layer because he is harvesting from a starter, and I usually don't because between whirlfloc at ten minutes and an immersion chiller that gets the wort below 60C in well under ten minutes bugger all trub ends up in the wort and I can easily scrape yeast off the top. Unless I dry hop, in which case I either would't bother, or would rinse.

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Hi Quokka,

 

Interested to hear more about the PH adjustment, I woudl have thought 2.2 is too acidic for the yeast, and they would be happier at around beer ph of say 3.6 to 4.2?

 

In your method, does the solution dilute into the yeast and result in a PH closer to 4?

 

I used to wash my harvested yeast a bit with boiled water, unadjusted, and found the shelf life in the fridge not so good, since reducing the amount of water I wash with dramatically. the storage life has increased. I just used a Kolsch WLP 029 that I had in the fridge since early feb, 4 months, I used a 2L starter to get it going and it was fine after that long.

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2.2pH is the old figure used for acid rinsing - it's a level that will kill bacteria whilst leaving the most good yeast alive (there are nasty yeast that are better at producing off flavours than alcohol.)

 

Beer tends to have a pH between 4 and 5, plus around 5% alcohol - believe it or not, the original reason for making it was to preserve incredients, not to get drunk!

 

So I picked the old 2.2pH as you will probably end up in the 3-4pH range, providing a reasonable level of protection without killing off too much yeast. Keeping the beer or treating with glycerine and freezing is better, but it isn't a bad substitute.

 

Try to keep that beer on top when refrigerating yeast stock - if you need to rinse you can do it when you remove from the fridge for brewing.

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Probably fine. I know I don't harvest from fermenter trub but the harvested yeast I take from my yeast starters only usually has 2 distinct layers as well. Never had any problems' date=' and I don't bother rinsing/washing it either.[/quote']

 

Thanks Otto, colour is good too so I won't worry about it.

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Yes' date=' you have a nice clean sample and no need to rinse. The third layer is trub - leftover break, hop matter, crap like that. If you were missing the top layer of beer that protects the yeast it can be replaced with boiled water reduced to a pH of 2.2, same as you would if you rinsed it before storage.

 

Otto doesn't have a third layer because he is harvesting from a starter, and I usually don't because between whirlfloc at ten minutes and an immersion chiller that gets the wort below 60C in well under ten minutes bugger all trub ends up in the wort and I can easily scrape yeast off the top. Unless I dry hop, in which case I either would't bother, or would rinse.[/quote']

 

Sounds good Quokka, I will dump it in the next batch.

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Hi Ted. I have had that happen too, especially if I did not leave enough beer behind to swirl up the yeast cake, but it does not seem to make much difference. I just make sure to shake up the contents of the jar well before taking the volume that I need (sloppy slurry method)....Extract brews don't have as much trub as all grain batches, especially if you don't dry hop. I don't harvest from brews that I dry hop, as I dry hop commando style.

 

If you were missing the top layer of beer that protects the yeast it can be replaced with boiled water reduced to a pH of 2.2' date=' same as you would if you rinsed it before storage.[/quote']

 

Are you sure about that Quokka? It is my understanding from vinegar making that yeast don't like pH <3.2.

 

I just checked the yeast storage chapter of my copy of "Yeast," by Chris White and Jamil Zainashef and they don't mention anything about storing under water with a pH of 2.2. In the chapter on yeast harvesting they talk about rinsing the yeast with sterile water. They also mention acid washing, in a solution with pH 2.0-2.5. But they caution that some yeast strains do not tolerate this very well, and that one should limit the wash to 60-90 minutes; you then throw the whole business in the FV, as you want to feed the yeast ASAP after the acid wash....Reading between the lines, it sounds like they are not fans of acid washing.

 

Have you actually brewed a beer with yeast after storing it in a pH 2.2 bath? How long did you store it? Which strain was it?

 

Cheers,

 

Christina.

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Yes, or somewhere thereabouts. A few years ago everyone was recommending washing yeast, and I found I ended up with infections. My old texts actually recommended no lower than 2.2pH for washing, though it does depend on the strain - the higher the alcohol tolerance of a yeast, the lower the pH it can withstand. The kind of yeast that make vinegar make bad beer, hence the desire to lower the pH below 3. I don't recall the strain I was using, but there weren't a lot of choices back then and acid washing was method we used to attempt to clean up our yeast.

 

As I pointed out several times I do not recommend this - keep the yeast under the beer until ready for the next batch. I have done this many times, up to several months.

 

I don't know how much of the yeast on the top layer died substituting an acid solution, but it was re-used a little over a month later as I recall (decanted and mixed with boiled water before pitching) and the ferment worked just fine.

 

I suppose you could make up a solution of pure ethanol to 5% and drop it's pH to about 4.4 to simulate beer, but have read other sources which suggest there is more to maintaining yeast health than just sanitation.

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  • 4 weeks later...

Hijacking this thread instead of starting a new one.

Made a starter from harvested 1469 about 4 days ago, 1.4litre(~200B cells), and saving 0.6litre(~100B).

I have found the 1469 a slow floccer, and the 1.4litres was put in the fridge for about 2 days and was still pretty hazy, although there was a nice creamy layer about 7mm thick on the bottom of the preserving jar.

I poured of about half of the beer before pitching into an ESB last night.

But now I am thinking that I should have pitched the whole 1.4L, due to the yeast not completely floccing.

Would like to know what other yeast harvesters think?

Was probably a bit of an under pitch already as the predicted OG is 1.058.

Was thinking of rehydrating the Coopers yeast and throwing it in this morning.?

The krausen is just starting to form now so I suppose I should get to it quick before too much alcohol is made?

Back to work in a few days so can't monitor the ferment and don't want a stuck ferment when I come home etc

 

Cheers

 

James

 

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Think I will leave it be for now.

Considering I used to just sprinkle on 11g of dry yeast and the beers were always fine.

Probably just over thinking it as usual.

The krausen is coming up now 12 hours after pitching.

 

Cheers

 

James

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It'll probably be fine although with an OG like that it probably should have been pitched with 200bn+ cells, depending on the batch size, unless you meant the 1.4L is what's left over after harvesting? If so then I'd just leave it. I haven't found 1469 to be a slow floccer though, except in the first 2 or 3 generations. Since then it's dropped like a stone in the starters and the main batches, but not before it ferments out properly.

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Yeah the 200Bn cells were pitched into the wort, and 600ml/ 100Bn saved for next time.

That is if they all made it after half the hazy beer was poured off!

Gonna get a 3L flask for the next brew so I can do 2.5L starters instead of just 2-2.1L

Think this the third or fourth generation of 1469, so should start to see an improvement in flocculation hopefully soon.

Enjoy flavour/creaminess the yeast gives the beer, but would like it to flocc a bit faster.

 

Cheers

 

James

 

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Maybe it's chill haze rather than yeast haze causing the starter to be cloudy. I've had some pretty hazy ones too but it doesn't seem to be yeast because if I do let warm up it goes pretty clear. I also enjoy that yeast in certain styles, I use it mainly in my red ale and English bitters, and I have used it for stout and porter as well, still re-using from a smack pack I bought a year and a half ago. w00t Next use will be 9th generation. I harvest about 800mL which generally nets between 130-150 billion cells. I use a 3L flask for ales too, even though most of them are still only 2-2.3 litres in size, because it also gives me more headroom for potential boilovers or krausen development when the yeast is pitched.

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  • 1 year later...

Coopers Kit International Series yeast is equal to, IMHO, US-05 for taste. I  would gladly use this Ale/Lager yeast if I could buy it.

However, when harvested from a previous batch and put in a capped PET in the fridge, all is good for a long period, and the PET is not "hard".

But unlike straight Ale yeasts - almost always US-05 - I  always have a volcanic eruption from the PET when I unscrew the cap to pitch it cold into my wort. This happens even though the PET is still only around 4c.

I love the brewing results from it though, and how great it is for bottle carbonation during winter, because the lager bits wake up and carbonate at lower than 18c.

The "volcano effect" makes it an interesting job to reuse Kit Int yeast. 

Anyone else noticed this?

Cheers

Edited by Worthog
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  • 1 month later...

I have just had poor bottle fermentation from a US-05 batch of beers. This has happened because during the 2 weeks bottle conditioning at 20c, the bottles have dipped to low temperatures o/nights to lessen carbonation time.

The batch was between 2 Coopers Kit Int yeast batches, which, under the same conditions have carbonated beautifully over 2 weeks.

I have previously posted that I love Coopers KitInt yeast because it's taste is similar to US-05 but it has superior fermenting capabilities at low temp due to it's ale/lager hybrid makeup.

But it is not commercially available.

Does anyone know of another hybrid brand with similar taste, that I could use during winter?

What would happen if I slurried a batch with both US-05 and S23 at the same time?

Cheers

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38 minutes ago, Worthog said:

But it is not commercially available.

What would happen if I slurried a batch with both US-05 and S23 at the same time?

Cheers

Id try a satchet each of mauribrew 514 and mauribrew 497 and see how that goes.

I would not use S23 at ale temps. Well i wouldnt use it at all really but definitely not at ale temps.

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