The cold hard truth about rinsing yeast with boiled water

[cervid]

Lol... My wife was asking suspect questions about yeast one day too... Different yeast honey, don't worry!

The way he just posted is the best way to do it. That's how a lab does it. But, it's a whole other level than washing and splitting starters with nutes and only dme, which is above repitching off a fermenter..and that technique is really the lowest rung. Breweries make the same exact beer over and over. It's how these yeast strains became isolated to begin with. Repitching that same yeast onto the same beers, in the exact same conditions is different than just repitching any slurry, or storing said slurry.

I thought this post was about washing and re pitching, not slanting.

 

[cervid]

Kai experiments are dealing with the growth of yeast in those enviroments, not just the storage so you can't make a direct comparison between the two cases. The Maltose Falcon was way to much info to quickly skim over - so I will not comment on that until I can read it properly

Isn't that your main concern in a starter? Healthy growth? Wouldn't repitching a starter with those elements hamper growth? Wouldn't washing with something help to eliminate them? That article is relevant.

EAZ? I thought diauxic shift was bad, and one reason to not store in alcohol. Is that not right?

 

[mattd2]

Isn't that your main concern in a starter? Healthy growth? Wouldn't repitching a starter with those elements hamper growth? Wouldn't washing with something help to eliminate them? That article is relevant.

But we are not talking about starters, etc. here. What is proposed is storing havested yeast in the green beer. If the alcohol/hops/grist make-up was so detrimental to the yeast's health then it would have never fermneted the orignal batch.
Basically EAZ has said instead of wasting time boiling water, etc. (which could potentially have contaminates in it anyway - not likely but potentially) an easier way is to use some of the green beer to suspend the yeast and then havest that.
Compared to the washing tutorial the differences are (in bold)
-Rack beer to bottling secondary/bucket/keg - leave 500ml of beer ontop of the yeast cake
-Do not add any additional water
-Swirl and let sit
-Decant into santised (washing tutorial assums mason jars to be sterilised during the boil) container
-Washing:Let container sit for 20 minutes, then decant again to smaller containers and store in fridge / Beer method:Store container in fridge vented
-Use within 2-4 weeks

You can then either take the yeast you have got and make a starter as you would with the washed yeast (decant & pitch into fresh starter wort) or if you retreive sufficent volume directly pitch into the fermenter

EAZ? I thought diauxic shift was bad, and one reason to not store in alcohol. Is that not right?

I think that was a tangent - I wouldn't expect someone to actually carryout what EAZ suggested could be done

 

[cervid]

What about the petite mutants caused by fermenting an entire batch of beer over a week? Beer who's main goal for the test was to grow 3-4 times, then make alcohol, and likely had no nitrogen added to it.

I'm talking about starters because I'm talking about harvesting off of them. I think you're missing that. I'm saying that is better than harvesting off of a fermenter and then giving reasons for it. I'm not saying it's better than slanting or plates.

 

[EarlyAmateurZymurgist]

He says the best way to do it is to crop and repitch because that's how breweries do it. But not all. And they re pitch immediately. If you read the article from kai and from maltose falcons, well, they see it differently.

You have to scroll down and read about roasted Malts and hops. At least one of these is in that beer you crop off, maybe both.

Here's the other link. Read the last line of her summary in the first section. Also, she talks about long term storage and washing later down.

http://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices

I know Maribeth Raines and her former business parter Jeff Mellem. I consider Maribeth to be one of my mentors.

You are taking one sentence in a long paper and making it the center of your thesis. Maribeth states that trub can be removed using sterile (not boiled) or acidified water (true yeast washing), but follows that statement up by saying that she doesn't bother to do it.

Here's what Maribeth stated in the paper:

"Prior to pitching, the trub (cold break) can be removed by washing the yeast with sterile water or acid. I usually don't bother; instead I only resuspend the top two-thirds of the yeast for pitching and discard the remainder. "

The sentence that follows the sentence on which you are basing your thesis is the process that I have been preaching for reusing yeast since I joined this forum. This practice was common knowledge in the amateur brewing community at one time.

With that said, how long have you managed to keep a culture viable via rinsing and storing it under boiled tap water? I kept Brewtek CL-170 and CL-660 cultures alive for ten years on agar slants (I also kept a real Ringwood culture that I isolated alive for ten years). If you have done your homework, you will know that CL-170 and CL-660 were Maribeth's cultures. I would suspect that the Brewtek CL-50 culture that became Denny's Favorite 50 was also kept alive on slant long after Maribeth shuttered Brewtek.

 

[EarlyAmateurZymurgist]

EAZ? I thought diauxic shift was bad, and one reason to not store in alcohol. Is that not right?

Diauxic shift is only bad if it occurs in one's finished beer. It's one of the reasons why we try to avoid aerating fermenting beer. The goal of culture maintenance and propagation is different in that the medium is a not an end product.

 

[cervid]

.

 

[cervid]

Diauxic shift is only bad if it occurs in one's finished beer. It's one of the reasons why we try to avoid aerating fermenting beer. The goal of culture maintenance and propagation is different in that the medium is a not an end product.

So, considering what you are doing.. With slants, etc is still a ways off for me. Is harvesting off starters to store for a month at least a better way than off a fermenter? Would adding more nutes at the end of the starter fermentation before storage be good?

Wasn't she Brewtek?

Also, i haven't kept any yeast very long. I use them up, and buy more if i need to. I have no rare yeast. As i said, I'm just getting ready to start keeping yeast longer, off of starters. Mainly, to keep this ECY21 as long as I can. I've read about glycol in the freeze. Do you think that's even wort it,.considering regular freeze temps?

 

[cervid]

I'm on my phone.. It's horrible. Sorry for spelling or gramar.

 

[mattd2]

...All these were pointing to.. Harvesting off a a starter and storing is better than harvesting off of a fermenter and storing.

Do you agree with that?

Hey mattd, do you know any Drinkrow's in New Zealand?

I think havesting from a starter would be better than from a fermented batch - but that seems to be off topic from the original intent of this thread which was to say washing yeast with boiled water is not needed and could actually be detrimental.
And then things went completly of the tracks with agar and slanting and cyrogenics and Hans Solo... wait what????

Sorry, don't know any Drinkrow's? What are they exactly?

 

[EarlyAmateurZymurgist]

I thought this post was about washing and re pitching, not slanting.

No, this thread is about the fallacy that rinsing yeast with boiled tap water is more beneficial to a culture than leaving it in its own ecosystem. The slanting post was added as a viable long-term yeast management solution.

 

[mattd2]

No, this thread is about the fallacy that rinsing yeast with boiled tap water is more beneficial to a culture than leaving it in its own ecosystem. The slanting post was added as a viable long-term yeast management solution.

I brewed a 23 litre batch and kegged 19 litres off it last night... now I can't be bothered bottling the rest. can I just leave it in the fermenter in the fridge and call it a large yeast havesting container... If my wife asks me to get rid of it will you back me up... hahahaha just joking

 

[cervid]

.

 

[EarlyAmateurZymurgist]

Zainasheff and White, in their book "Yeast" never seem to make your points in their discussion of yeast harvesting and they recommend that harvested yeast be rinsed.

Nowhere in the text do the authors state that yeast should be rinsed with boiled water before repitching. The authors merely answered the question "How do I select the only the best yeast if harvesting the entire contents of the fermentor?" on page 168. I showed people who to crop only the best yeast from the fermentor without discarding the culture's ecosystem, which is more beneficial than it is harmful. Liquid culture management is about making trade-offs. It is easier to propagate a less viable culture than it is to clean up an infected culture.


While boiled wort is not sterile, it has a 5.2 pH, which helps to keep wild microflora at bay until the culture can lower the pH even further. Boiled tap water usually has pH 7.0 or higher. Replacing the green beer with boiled water raises the pH of the culture.


By the way, if you want to read a real brewing yeast textbook, pick up a copy of Brewing Yeast and Fermentation by Christopher Boulton and David Quain.

 

[AnOldUR]

Zainasheff and White, in their book "Yeast" never seem to make your points in their discussion of yeast harvesting and they recommend that harvested yeast be rinsed.

Nowhere in the text do the authors state that yeast should be rinsed with boiled water before repitching. .

Page 168 and 169 go into detail about rinsing with sterile water. Pretty sure they're referring to boiled water. Copyright is 2010. Any links to where they changed their stand on this?

... Yeast rinsing with a relatively clean pitch of yeast. Starting with a havested slurry that has settled , decant the beer, add back sterile water, shake vigorously, and then let stand for 10 to 15 minutes ...

I admire your conviction, but my layman take would be that even if boiled water is not sterile, it’s plenty sanitary for our purposes. That a slurry stored at 35 degrees may not be totally dormant, but it’s plenty dormant for our purposes. And that if any bugs do get past your process, they are more likely to feast on the unfermentable sugars in old beer than boiled water. But I’m a machinist, not a scientist.

 

[Bottoms_Up]

Compared to the washing tutorial the differences are (in bold)
-Rack beer to bottling secondary/bucket/keg - leave 500ml of beer ontop of the yeast cake
-Do not add any additional water
-Swirl and let sit
-Decant into santised (washing tutorial assums mason jars to be sterilised during the boil) container
-Washing:Let container sit for 20 minutes, then decant again to smaller containers and store in fridge / Beer method:Store container in fridge vented
-Use within 2-4 weeks

Where can that tutorial be found?

 

[mtnagel]

Where can that tutorial be found?

https://www.homebrewtalk.com/f163/yeast-washing-illustrated-41768/

 

[mtnagel]

Let me see if I have this correct:

- If I want to harvest yeast after fermentation and I'm going to use it to ferment another batch within 1 month, I can just grab some of the slurry from the fermentor and store it in a fridge before reusing it in another batch.

- If I want to harvest yeast after fermentation and I'm NOT going to use it to ferment another batch within 1 month (and I don't want to do agar slants and freezing), I can just grab some of the slurry from the fermentor, but every month, I should basically make a starter with it and feed it fresh wort to keep it viable.

Is that correct??

 

[cervid]

Certainly you can infect beer with bugs like Lacto, Pedio, Brett, etc that will ferment sugars and compounds sacc won't. But, there are a lot of others that can live in water, or fall into your yeast as handling it, etc that could grow to make mold over time. Or grow and then get killed off by the fermentation and leave some off tastes

I do agree though that boiled water is good enough for how tight the quality control can be in a home brewing environment. I also think that regardless of whether it's under beer or water, you still have to use it in the same amount of time and just don't see the beer increasing it's decrease in viability. Certainly not enough to adjust a calculation for.

But, at the same time, I am inclined to look at my starters, leave an amount of beer in there to get an amount that will pour into the number of jars I want to use and shake and dump, rather than wash. Just because it's easier and for how long I'm storing them, he makes enough points to convince me.

Jamil is a programmer turned home brewing expert. Why do you think White wrote that book with him? Regardless, after dealing with all the screwed up recipe calculations and how they wrote those recipes in Brewing Classic Styles, and all the info out there that contradicts what they say on yeast.. well.. I doubt I'll be buying any more of Jamil's books. But, I do think he has a lot of authority on style and taste.

The next book I'll most likely be buying is Ray Daniels Designing Great Beers.

 

[cervid]

Let me see if I have this correct:

- If I want to harvest yeast after fermentation and I'm going to use it to ferment another batch within 1 month, I can just grab some of the slurry from the fermentor and store it in a fridge before reusing it in another batch.

- If I want to harvest yeast after fermentation and I'm NOT going to use it to ferment another batch within 1 month (and I don't want to do agar slants and freezing), I can just grab some of the slurry from the fermentor, but every month, I should basically make a starter with it and feed it fresh wort to keep it viable.

Is that correct??

That's what I've gathered from a lot of sources. You could probably go more than a month. A lot of others have. Also, if you plan to store for a year, you can find a lot of info about using vegetabl glycol and storing them in a regular freezer. You don't need a deep freezer.

 

[RonPopeil]

OK so i understand the argument here but what would the proposed new process be if slanting isn't possible.

My typical process is actually for new vials of yeast. I make a large volume (3-4L) started at an OG of ~1.030 and pitch an entire vial to it. Once it flocs out I decant the clear fluid and pitch another large volume at ~1.050 OG. From the calculators I've used this should be around 350B cells per pint. I decant half of this fluid once the yeast flocs and then agitate it back up before bottling in sanitized jars.

So in this process the yeast is stored in a remainder of the second starter wort within an ice tea bottle or spaghetti sauce jar which i've kept tightly sealed. Aside from freezing: Is there a better way?

 

[RonPopeil]

Let me see if I have this correct:

- If I want to harvest yeast after fermentation and I'm going to use it to ferment another batch within 1 month, I can just grab some of the slurry from the fermentor and store it in a fridge before reusing it in another batch.

- If I want to harvest yeast after fermentation and I'm NOT going to use it to ferment another batch within 1 month (and I don't want to do agar slants and freezing), I can just grab some of the slurry from the fermentor, but every month, I should basically make a starter with it and feed it fresh wort to keep it viable.

Is that correct??

yeah same questions. and at this point how do i keep track of cell counts and keep my pitch rates in order?

 

[mtnagel]

yeah same questions. and at this point how do i keep track of cell counts and keep my pitch rates in order?

You should still be able to use MrMalty's "repitching from slurry" calculator. The thing that gets me though is the thin to thick slurry slider. You can get wildly different answers when you move that from side to side and I really don't know how to judge what I have.

I once harvested the "slurry" from the fermentor and it was so thick it was almost a solid (I don't like to leave any beer behind when transferring ). It wouldn't pour that's for sure. Even moving it to "thick," I'm sure mine was more concentrated than that. Kind of hard to predict quantities in that case. But I've always heard it's better to over pitch than under pitch, so I just guesstimated. Beer came out great!

 

[drksky]

So, I'm reading the Maltose Falcons article and came across this:

If you plan on storing the yeast for more than a couple weeks, it is best to wash the yeast with some yeast after a day or two in the refrigerator.

Wash the yeast with some yeast? Is this a typo?

 

[Bearfoot]

yeah same questions. and at this point how do i keep track of cell counts and keep my pitch rates in order?

I found this thread quite helpful. Had to download a scientific calculator widget but it was worth it.

 

[RonPopeil]

I found this thread quite helpful. Had to download a scientific calculator widget but it was worth it.

Thanks I'm going to have to check that out!

 

[Bottoms_Up]

https://www.homebrewtalk.com/f163/yeast-washing-illustrated-41768/

Thank you. I have seen that but wasn't sure that was the one being talked about. There's another great video of yeast washing on Billy Broaz's site:

http://billybrew.com/yeast-washing

 

[Orthobrewsky]

Nowhere in the text do the authors state that yeast should be rinsed with boiled water before repitching.

That's true, but I think you are splitting hairs just a bit and it's a hair I've already split when I mentioned that they did recommend rinsing with "sterile" water before repitching. Yes, spores can survive boiling, but I guess they can probably survive fermentation as well and if you leave your pot uncovered at all while chilling, some may be slipping in. Also, if you are using the same water for brewing that you use for rinsing, it is likely to have the same initial concentration of spores in it before exposure to air. Thus, I would think that the concentration of spores in the rinsed sample is likely to be a bit less than the concentration in the sample harvested as you recommend, considering that the boiled water started out the same as the brewing water and had less exposure to air.

While boiled wort is not sterile, it has 5.2 pH, which helps to keep wild microflora at bay until the culture can lower the pH even further. Boiled tap water usually has pH 7.0 or higher. Replacing the green beer with boiled water raises the pH of the culture.

And, as you have pointed out, alcohol is far more hostile to most of our common contaminants than to yeast. Those are some issues certainly worthy of consideration. When pondering them it occurred to me that simple (as opposed to thorough) rinsing, as is described on some pages referenced in this thread, probably gives us a sample for storage which is about half beer, so the pH might still be pretty decent and there would be enough alcohol to do some good too. So, since I had an old sample in the frig resulting from a simple rinse, I decided to do some tests. The liquid sitting above the yeast read as follows:

5.1 pH
2.3% ABV (The beer was 4.6%)



That still sounds somewhat protective and the added water thinned out the cake, allowing me to more readily separate yeast from trub. Finished beer has somewhat lower pH and higher alcohol, but rinsing also lowers the concentration of potential food for wild organisms and then the sample goes straight to the frig. Those electing for a thorough rinse would leave wild bugs nothing to eat, while losing the buffering capacity of the beer. However, they could easily adjust pH as is done to a greater degree in actual washing.

I'm convinced your recommendation has merits and advantages, but I'm not convinced that rinsing with boiled water is a bad thing and it has its own advantages. I think that the data from some experiments should be brought to light before concluding emphatically that one method is better than the other.

By the way, if you want to read a real brewing yeast textbook, pick up a copy of Brewing Yeast and Fermentation by Christopher Boulton and David Quain.

That looks very nice and I put it on my Amazon wish list. For now, the $80 price tag causes me to hesitate, but I thank you for the recommendation.

 

[AnOldUR]

So, this is the wrong way?

1. Always make an effort to transfer as little as possible hop and break material into fermentor. Never dry hop in primary.

2. Cold Crash primary a few days after fermentation is complete using a slow temperature ramp up. The cold crashing aids in dropping some of the less flocculent yeast.

3. Carefully tilt cold carboy so that all but an ounce or so of beer can be siphoned from on top of the compact cake.

4. Rinse cake with refrigerated water that has been boiled to sanitize. Swirl and give it a short time to settle. Decant leaving as much non-yeast trub behind as possible.

5. Place cold slurry immediately in fridge to keep yeast in its dormant state.

Works every time for me . . . (avatar worthy )

 

[mtnagel]

That is an impressive amount of very clean looking yeast! Well done.

FYI, Halloween is over