The cold hard truth about rinsing yeast with boiled water

[Bottoms_Up]

If one was to go from a hoppy beer (IPA) to something like a blonde with low bitterness you might consider it, but it would be better to plan your new batches of so you progressively increase in bitterness and alcohol.

I guess you expressed my concern. I basically only brew lagers, which are very susceptible to off-tastes. So any test should also include light ales and/or lagers.

 

[Bottoms_Up]

out of a given yeast cake you are only using a cup, more or less, so you would not have all of the trub. the next cake would give up a cup and so on. i you are pitching the whole cake each time you would have all of the trub but i don't think you are suggesting that.

That would be true for ales. But I basically only brew lagers, which require at least two or three times as much slurry. Also, I brew 10 gallons at a time, which means double that amount. So, yes I usually use all of the slurry from a 5 gallon batch (and save the slurry from the other 5 gallon carboy).

 

[Bottoms_Up]

What if you boiled the beer? You would get the benefits of the beer while evaporating some or most of the alcohol off. A 15-minute boil willl leave you with roughly 40% of the original alcohol, so a 5.5 Bud would end up at 2.2

Is that too much? What would be the negatives with this method?

That sounds reasonable to me.

 

[mattd2]

Here's a Wyeast source that stresses the use of LOW alcohol content:

Keys to Successful Yeast Storage:

Keep the yeast cold, 34°F (1°C).
Store in sterile, vented stainless steel container.
Store under a 3 to 4 inch layer of low alcohol, low hop beer.
Store yeast from only lower alcohol beers.
Minimize trub.
Minimize exposure to oxygen.
Store under a blanket of CO2 with minimal positive pressure.
Use as soon as possible, preferably within 3 to 4 days.
Test for viability, cell count, and contamination prior to pitching.

Source:
http://www.wyeastlab.com/com-yeast-storage.cfm

John

But they don't state what "low alcohol" beer is. And i would expect that they are meaning more reusing yeast from a 10% beer is not a great idea, rather than 5% beer. Most yeast is ok up to 9-10% (IIRC) so 5% should be in their comfort zone.

 

[mattd2]

That would be true for ales. But I basically only brew lagers, which require at least two or three times as much slurry. Also, I brew 10 gallons at a time, which means double that amount. So, yes I usually use all of the slurry from a 5 gallon batch (and save the slurry from the other 5 gallon carboy).

But what is being suggest is basically taking the same approach as washing the yeast but instead of racking all the beer off the yeast and then adding some water back, the process is to leave some beer in the fermenter and "wash" the yeast with that. You are washing with basically the same amount of liquid, the only difference is one is boiled water adn the other beer.
You could still do the multi satge "washing" if you wish - take the yeast that you get from the intial swirl/sit/decant, let that sit a bit more and then decant into a smaller jar.
As far as the going from least - most flavour beers, this is suggest for washing as well.
And your argument that you need more because you brew 10 gallon batches is not that valid since you will be pitch the greater volume into the larger volume - the ratio will be the same independant of batch size.

 

[Bottoms_Up]

But what is being suggest is basically taking the same approach as washing the yeast but instead of racking all the beer off the yeast and then adding some water back, the process is to leave some beer in the fermenter and "wash" the yeast with that. You are washing with basically the same amount of liquid, the only difference is one is boiled water adn the other beer.
You could still do the multi satge "washing" if you wish - take the yeast that you get from the intial swirl/sit/decant, let that sit a bit more and then decant into a smaller jar.
As far as the going from least - most flavour beers, this is suggest for washing as well.
And your argument that you need more because you brew 10 gallon batches is not that valid since you will be pitch the greater volume into the larger volume - the ratio will be the same independant of batch size.

Yes, but I was under the assumption that the extra water would dilute the alcohol content, especially if the beer was strong - thus you would save less of the beer in your carboy. But if one is making low alcohol beer (e.g. 5% or less), then I can see using just the beer rather than adding some water.

Regarding my argument re: the 10 gallon batch, perhaps I wasn't very clear. Although I mash and boil ten gallons all at once, I subsequently split it into two separate five-gallon carboys for fermenting and kegging. Thus I use ALL of the slurry from a previous five-gallon carboy and split it between the two five-gallon carboys. I keep the slurry from the other previous five-gallon carboy to split between the two five gallon carboys resulting from my next ten gallon batch.

 

[Bottoms_Up]

But they don't state what "low alcohol" beer is. And i would expect that they are meaning more reusing yeast from a 10% beer is not a great idea, rather than 5% beer. Most yeast is ok up to 9-10% (IIRC) so 5% should be in their comfort zone.

I agree - that's likely one of the reasons why the proportions of DME and water used in a yeast starter results in a low alcohol starter. The other reason pertains to an optimization of yeast growth and vitality depending on the concentration of yeast in the Erlenmeyer flask.

 

[The10mmKid]

Nice write-up EAZy. Just food for thought...
I have heard of using BMC (Bud/Miller/Coors) lite products as your wash water in place of boiled water. This eases the process of washing a bit, and has all the benefits of keeping the yeast under beer. Open a glass bottle (or 2) of Miller Lite, flame the opening, dump into bucket/carboy, swirl...&so on. What do you think of this method?

Sent from my Nexus 7 using Home Brew mobile app

There a a few cans of BMC Lite sitting in the back of the fridge, hidden by the homebrew that I just can't force myself to drink.

Thanks to you 05m50dan, they now have a purpose in life.

I'll put it to practice this W/E,
'da Kid

 

[cervid]

i don't think that is an issue at all, the amounts are too small and the beer is not adversely affected in any event. have you watched a brewery reuse yeast? they pump it straight from the cone into the next fermentor, no washing. i am totally ready to change my practices and publicly admit i was wrong if i saw any evidence of trub, dead yeast, or break material causing any harmful changes to my beer, but so far i have not. i would love to see any evidence to the contrary, not for the sake of being right or wrong but because it would be very interesting.

They also pull the trub out of the conical early in fermentation. Then they pump the middle yeast slurry for re use. There are still yeast in the fermenting beer. They don't wait for full fermentation and then do it. So, they have less alcohol and no trub in what they pump out. Also, it has been proven that any hops affects yeast reproduction negitavely. Hops are worse than the hot break proteins, and if you get a cold break, that's yeast food.

The idea of NA beer is interesting.. It would be easy to pour one at room temp.. Boiling beer would simply introduce it to more bacteria. If we are talking about sterility, that's just one more step.

The way I'm going, I'm harvesting my yeast off my starters. That's why I got a 5L flask. However, I am inclined to decant the spent wort and use NA beer to wash it and store in the fridge. At least the ph is lower than water and it has no oxygen. Freezing with vegetable glycol has been well established.

 

[kako187]

Wow. Learn something new everyday. I was unaware that BMC was beer

 

[cervid]

I was unaware that BMC was beer

It's actually InBevMillerBanquet.

 

[cervid]

You know what's sad.. Not one of those the companies are owned by an Amercian company any longer..

 

[eastoak]

They also pull the trub out of the conical early in fermentation. Then they pump the middle yeast slurry for re use. There are still yeast in the fermenting beer. They don't wait for full fermentation and then do it. So, they have less alcohol and no trub in what they pump out. Also, it has been proven that any hops affects yeast reproduction negitavely. Hops are worse than the hot break proteins, and if you get a cold break, that's yeast food.

The idea of NA beer is interesting.. It would be easy to pour one at room temp.. Boiling beer would simply introduce it to more bacteria. If we are talking about sterility, that's just one more step.

The way I'm going, I'm harvesting my yeast off my starters. That's why I got a 5L flask. However, I am inclined to decant the spent wort and use NA beer to wash it and store in the fridge. At least the ph is lower than water and it has no oxygen. Freezing with vegetable glycol has been well established.

i'm pretty sure that breweries do it all kinds of ways, there is yeast and trub throughout the cone in various concentrations, but the point is there is no evidence that trub is harmful to beer. when i go down to drake's brewery for fresh yeast there is always a good bit of trub in the flask (2 or 5 liter flask) as far as hops affecting the yeast this is the very first time i've heard someone suggest that, could you provide more info on that?
just to be clear, i'm not saying that people should not wash yeast, what i'm questioning is it's usefulness, are you really avoiding anything that would harm your beer? i say no.

 

[cervid]

http://braukaiser.com/blog/blog/category/science/yeast/

He's really the only guy out there doing experiments lately Ive seen. If you're interested in yeast, you really should follow him.

 

[cervid]

i'm pretty sure that breweries do it all kinds of ways, there is yeast and trub throughout the cone in various concentrations, but the point is there is no evidence that trub is harmful to beer. when i go down to drake's brewery for fresh yeast there is always a good bit of trub in the flask (2 or 5 liter flask) as far as hops affecting the yeast this is the very first time i've heard someone suggest that, could you provide more info on that?
just to be clear, i'm not saying that people should not wash yeast, what i'm questioning is it's usefulness, are you really avoiding anything that would harm your beer? i say no.

If you harvest from a fermenter the evidence says yes, you are doing something that may harm your yeast. Or, at least its not optimal.

You can't compare a brewery to home brewing. Not unless you know their entire process start to finish. Some crop top in open fermenters, Firestone walker uses a burton union. You can't just say"that's how the breweries do it" based on a visit to get yeast.

 

[eastoak]

If you harvest from a fermenter the evidence says yes, you are doing something that may harm your yeast. Or, at least its not optimal.

what evidence? to me the evidence it the beer i make and it's great? i would love a peek of the evidence you have, in all sincerity, i'm here to learn.

 

[cervid]

You should follow the link and read before double posting about how great your beer is. Thats pretty subjective...

 

[eastoak]

read this short thread from probrewer http://discussions.probrewer.com/showthread.php?35078-Nano-Brewery-Yeast-Harvesting-Storage

i'm not basing my views on a visit for yeast to a brewery.

 

[eastoak]

You should follow the link and read before double posting about how great your beer is. Thats pretty subjective...

did you post your source for the hop thing?

 

[bob1852]

http://braukaiser.com/blog/blog/category/science/yeast/

He's really the only guy out there doing experiments lately Ive seen. If you're interested in yeast, you really should follow him.

Yeah, expecting to find science based answers on HBT (except for Martin and AJ's incredible knowledge on water chemistry) isn't gonna happen. This forum, while great, is still too full of the "well I do [this] and it works great for me so don't worry about it" or "I think I read somewhere to do [this] so that's what you should do" posts that drown out the few that actually have done the experiments or read the peer reviewed literature that is out there.

I read most/all of Kai's stuff, but outside of slanting individual colonies, I don't believe he's posted about washing/storing yeast with boiled water, wort, beer, BMC, etc...

 

[cervid]

I'll take what kai says over a 3bbl nano brewery who uses dry yeast. It's not an argument.. Slow down, read the posts, follow the link, and have a discussion. Did that nano brewer give a speech at the NHC with any contemporary experiments or evidence? That seemed more like a home brewer turned nano brewer detailing how he does something.

 

[eastoak]

I'll take what kai says over a 3bbl nano brewery who uses dry yeast. It's not an argument.. Slow down, read the posts, follow the link, and have a discussion. Did that nano brewer give a speech at the NHC with any contemporary experiments or evidence? That seemed more like a home brewer turned nano brewer detailing how he does something.

you win.

 

[cervid]

Yeah, expecting to find science based answers on HBT (except for Martin and AJ's incredible knowledge on water chemistry) isn't gonna happen. This forum, while great, is still too full of the "well I do [this] and it works great for me so don't worry about it" or "I think I read somewhere to do [this] so that's what you should do" posts that drown out the few that actually have done the experiments or read the peer reviewed literature that is out there.

I read most/all of Kai's stuff, but outside of slanting individual colonies, I don't believe he's posted about washing/storing yeast with boiled water, wort, beer, BMC, etc...

I don't recall seeing that from him. But, his recent stuff deals with different maltsand hops. That one link basically shows why harvesting off a primary isn't optimal. I've pitched right onto yeast cakes, don't get me wrong... But look, i read scientific articles for work all the time. When i read stuff like that, i try to evolve my technique.

 

[cervid]

The only article I've read about washing was from the girl in maltose falcons. That's 5 years old at this point, but still relevant I think.

 

[mattd2]

I don't recall seeing that from him. But, his recent stuff deals with different maltsand hops. That one link basically shows why harvesting off a primary isn't optimal. I've pitched right onto yeast cakes, don't get me wrong... But look, i read scientific articles for work all the time. When i read stuff like that, i try to evolve my technique.

Can you elaborate why that your link to Kai's work shows what the OP is suggesting isn't optimum? The only thing I could see is the effect of 20°P (1.083) wort on yeast health, but lower gravity did not have an effect.

 

[EarlyAmateurZymurgist]

EAZ, what is your take on freezing cultures rather than slanting them, in a manner similar to described in this thread? Keeping cultures in small vials in the freezer is more conducive to my circumstances than is messing around with agar agar and such. Just curious what you think of that approach. I've been using it for a couple months with several cultures and so far so good.

Cryopreservation really doesn't become a viable long-term option until one has access to a freezer that is capable of sub -80C temperatures (cell activity really starts to slow down at -136C, making cryopreservation the way to store yeast long term). Performed correctly, cryopreservation and resuscitation is no less labor intensive than slanting, and the viability period is shorter than slanting when the cryopreserved cultures are stored at -20C.


One doesn't need a lot of storage space to maintain a decent sized bank of yeast cultures on slant. Here's my current yeast bank.

The cultures shown above are stored on malt agar in Corning 9825-20 20mm x 125mm screw-cap culture tubes. I could fit my old thirty-plus culture bank in the container shown above with a lot of room to spare when I used Corning 9825-16 16mm x 100mm screw-cap culture tubes.


Here's the beauty of investing time in learning how to plate and slant yeast.

Southern Tier's Culture

The well isolated colonies in the red rectangle were transferred to slants (each colony is composed entirely of the offspring of a single yeast cell). Unlike frozen cultures, which are usually mixtures of the pitching culture combined with low levels of house or yeast manufacturing plant microflora, the slants that were grown from the colonies shown above are 100% pure pure cultures that were kept pure via aseptic transfer.


Scottish and Newcastle's Tyneside Culture

Cultures that I isolated from brewery sources via single-cell isolation

The culture tube on which the letters "HAR" can be seen on the Parafilm contains Harpoon's pitching yeast.

Cultures that I obtained from culture collections

The photos shown above illustrate the true beauty of learning how to plate and slant yeast. It frees a brewer from the constraints of having to wait for a yeast manufacturer to bring new cultures to market. One can even plate entirely new cultures from wild sources if one so desires.

 

[cervid]

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

 

[kako187]

Following

 

[EarlyAmateurZymurgist]

Who's saying that the alcohol is not good for the yeast - it stops a lot of other organism from being able to set up shop.

Ethanol is a net positive for the yeast culture in more than one way. The first and most obvious way is that ethanol is an antiseptic that is more harmful to wild microflora than it is to the culture. The second way is that ethanol is beneficial to a culture is that it is also a carbon source (a.k.a yeast food). We can cause a culture stored in a medium in which all of the glucose and all of the sugars that the culture can reduce to glucose have been consumed to consume ethanol by aerating it. The phenomenon is known as diauxic shift. The Crabtree effect does not come into play during diauxic shift because the glucose level is below the Crabtree threshold; therefore, the culture shifts into aerobic (a.k.a. respirative) consumption of ethanol as its food source. During respiration, a yeast cell converts a carbon source into water and carbon dioxide gas via the Krebs cycle. Ethanol can be thought of as inefficiently/partially digested yeast food. The molecular chemical formula for Ethanol is CH3CH2OH, which means that ethanol is a carbon-based compound.

 

[mattd2]

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

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