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1st Time Yeast Washing Question

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ted464

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Can someone take a look at these pics and let me know if I am doing this right, don't want to waste or mess this up. This is my first time washing yeast. I made a Cream Ale with Pacman yeast. OG was 1.047 and it appears to have finished out at 1.007. I had never used Pacman yeast before and it appeared to have settled out into large chunks. I added my boiled/cooled water and filled up three mason jars (one large, two small) with the intention to decant and pour those into two final small jars. My question is, is the bottom stuff which appeared to be the chunky yeast actually trub and/or dead cells? Do I only go after the white middle portion? I would hate to waste good yeast, since that is exactly what I am trying not to do. Sorry if this is a newbie question, but I've never done this before. Any help would be appreciated, thanks.

yeast.jpg
 

eluterio

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I just started doing this as well from my experience which is very little looks like to me you have tons of trub in this one. What do the other 2 jars look like.

If you have space in the others and what ive done is decant the good stuff into the other jars.
 
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ted464

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Thanks, that's what I thought. The other two look similar, just smaller. I have an extra jar, I'm going to decant all three into one. Even ending up with one jar to pitch next time is better than nothing.
 

eluterio

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I have come to the conclusion until I get it down pat to boil more jars then I would actually use. This way I can have sterilized jars ready incase I screw up. If all three look like this yes add to extra jar and if you have sterilized water left over and extra space in the jar fill with the water.

One Jar saves you 7 bucks or so for your next brew!
 
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ted464

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Sounds good, thanks.
 

finsfan

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Not sure what to tell you here since I have never washed yeast. My advice would be to start yeast ranching instead. It gives you 100% clean 1st generation yeast for as long as you take care of it. Next time you brew, make a starter that is more than you need, pour some out in a jar to save, fridge and decent starter wort, add boiled/cooled water on top of yeast cake and it will last many many months until you need to use it again :D
 

eluterio

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Not sure what to tell you here since I have never washed yeast. My advice would be to start yeast ranching instead. It gives you 100% clean 1st generation yeast for as long as you take care of it. Next time you brew, make a starter that is more than you need, pour some out in a jar to save, fridge and decent starter wort, add boiled/cooled water on top of yeast cake and it will last many many months until you need to use it again :D
Really??? Its this simple???? So for instance, make a 2 or 3 L starter Shake it up poor amount not going to use into jar, let it settle, decant, and add water?

If this is what you do then when you use the left over, make a starter larger like 2 or 3L again and repeat first few steps? Would this be 1st gen or 2nd?
 

finsfan

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Really??? Its this simple???? So for instance, make a 2 or 3 L starter Shake it up poor amount not going to use into jar, let it settle, decant, and add water?

If this is what you do then when you use the left over, make a starter larger like 2 or 3L again and repeat first few steps? Would this be 1st gen or 2nd?
It pretty much is. It will always be 1st gen if you dont wash it. The best part is you roughly know how many cells you have each time. For instance, friday I made a starter that was 1600 ML that totalled 280 billion cells. I only needed 230 billion so I poured off the extra (285ML) to get my 230 bil cells and was left with 50 billion cells to keep. Normally I have around 100-150bil cells to save but I didnt make a big enough starter. Use yeastcalc.com and this thread to get the details.

https://www.homebrewtalk.com/entries/yeast-harvesting-novel-approach.html
 

eluterio

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Wow, im speechless right now ill have to look into it to convince myself of doing this. Im planning on making a starter today or tomorrow. Most of the Ranching threads Ive read isnt this simple.
 

EarlyAmateurZymurgist

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Not sure what to tell you here since I have never washed yeast. My advice would be to start yeast ranching instead. It gives you 100% clean 1st generation yeast for as long as you take care of it. Next time you brew, make a starter that is more than you need, pour some out in a jar to save, fridge and decent starter wort, add boiled/cooled water on top of yeast cake and it will last many many months until you need to use it again :D
Everything that you recommend up to adding the boiled water is good advice. Under no circumstance should one dilute a yeast culture with boiled tap water. Storing yeast under boiled tap water is actually bad for the culture. Boiled water is not sterile, and it raises the pH of the culture. The best way for amateur brewers to store yeast is under fresh hopped wort or beer. Researchers have experimented with storing small amounts of centrifuged yeast under autoclaved distilled water; however, research with respect to storing large slurries under autoclaved distilled water is inconclusive.

With respect to yeast rinsing (yeast washing is an entirely different process), it's an amateur brewer-only process that was originally developed as a means by which to separate viable yeast from from trub and dead yeast cells. The practice has morphed over the years through folklore to include storage under boiled tap water. Currently, no peer-reviewed science exists that promotes storing yeast under boiled tap water over leaving it under green beer.

For those who think that I am full of it, here's a link to an article about yeast storage that was written by Chris White for BrewPub Magazine:

http://www.probrewer.com/resources/library/bp-healthyyeast.php

"Yeast is a living organism and is most happy and healthy when feeding on wort sugars. When fermentation is complete, yeast cells flocculate to the bottom of the fermenter. They then go into a resting state. Yeast under beer is fairly stable, and most brewers agree that the best place to store yeast is under beer."


"Storing yeast under water, as opposed to under beer, is becoming more popular. Sterile distilled water storage puts yeast in a resting state, and some reports suggest yeast can be stored in this manner for years, with no refrigeration. Storage under water is generally done with small quantities of yeast, which are then propagated in a lab. But it is possible that this can be applied to storage of yeast slurries. Some brewers are now trying this. The key is to use sterile distilled water and wash the yeast slurry several times in the sterile distilled water to remove any traces of beer. This is best done with a centrifuge, but that is impractical for most craft brewers. White Labs has had mixed success with sterile water storage, so time will tell if this procedure will work for craft breweries."


In practice, one does not need to rinse a crop. Pitching between 125mls and 250mls of mixed slurry will usually get the job done with no off-flavors. The key thing to remember when cropping is to handle the culture as little as humanly possible. One risks an infection event every time one handles a culture. It is an order of magnitude easier to propagate a weak clean culture than it is to clean up an infected strong culture.
 

finsfan

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Sterile distilled water storage puts yeast in a resting state, and some reports suggest yeast can be stored in this manner for years, with no refrigeration.
This is the reason I keep it under water, to keep it for long periods of time since I dont know when I will use it again. Im sure it will keep just fine under the starter wort but I prefer to use boiled water. As you even said, the results of experiments on both are inconclusive.
 

finsfan

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Wow, im speechless right now ill have to look into it to convince myself of doing this. Im planning on making a starter today or tomorrow. Most of the Ranching threads Ive read isnt this simple.
I would highly recommend it to any level of brewer. I am still learning myself but this is one easy step to build up a readily diverse supply of yeast and save money doing it :D
 

eluterio

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So im a bit confused.

EarlyAmateurZymurgist said this (Under no circumstance should one dilute a yeast culture with boiled tap water. Storing yeast under boiled tap water is actually bad for the culture)

However, while you continue to read his post it reads what finfan highlighted. Sterile distilled water. Is'nt this the same as boling water to get it to become sterile? Boiling off oxygen and bacteria therefore, making it sterile?


Sorry, I dont know how to quote each paragraph.
 

EarlyAmateurZymurgist

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This is the reason I keep it under water, to keep it for long periods of time since I dont know when I will use it again. Im sure it will keep just fine under the starter wort but I prefer to use boiled water. As you even said, the results of experiments on both are inconclusive.
However, you missed the point of the article. The practice only works for yeast that is been separated from everything else via centrifuge and stored under autoclaved distilled water. What you are doing does not put the yeast in a resting state; therefore, it does nothing other than introduce an infection vector into your yeast management program. Boiled water is not sterile. One has to autoclave (i.e., pressure cook) water to render it sterile. Tap water contains minerals whereas distilled water is completely mineral free. Centrifuged yeast that is stored under autoclaved distilled water goes dormant because there are zero nutrients in the solution.

The notion that storing yeast under boiled tap water is better for the culture than storing it under green beer is a amateur brewing myth that is not supported by science. Here's why storing yeast under boiled tap water is not a smart thing to do. First off, as stated above boiled water is not sterile. Spores survive 212F/100C moist heat. Secondly, yeast own a medium by consuming all of the dissolved oxygen, lowering the pH, and producing ethanol, which is toxic to most microflora. Replacing green beer with boiled tap water raises the pH of the culture and removes the ethanol while possibly introducing spores, which can now germinate because we have removed the culture's force field. Maintaining a yeast culture in liquid form is about making trade-offs. It is almost always better to trade viability for purity than it is to trade purity for viability.

With that said, a very good, very stable, and relatively easy to master long-term storage method is available to amateur brewers; namely, storage on agar slants. I have pretty much brewed with home cultured yeast since I made my fourth batch of beer over twenty years ago. I maintained several cultures on agar slants for over ten years. The only reason why these cultures did last longer is because I took an extended hiatus from the hobby. Every amateur brewer who is willing apply himself/herself can learn how to maintain and use slanted yeast. Heck, if Denny Conn had never learned how to use slanted yeast, there would be no Wyeast 1450 today. The culture known today as Wyeast 1450 was originally distributed on slant by a company called Brewer's Resource. It was a culture known as Brewtek CL-50 California Pub Brewery Ale. Brewtek was the brainchild of Dr. Maribeth Raines. Maribeth taught an entire generation of amateur brewers how to plate and slant yeast with her yeast culturing kit and pamphlet.
 

eluterio

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However, you missed the point of the article. The practice only works for yeast that is been separated from everything else via centrifuge and stored under autoclaved distilled water. What you are doing does not put the yeast in a resting state; therefore, it does nothing other than introduce an infection vector into your yeast management program. Boiled water is not sterile. One has to autoclave (i.e., pressure cook) water to render it sterile. Tap water contains minerals whereas distilled water is completely mineral free. Centrifuged yeast that is stored under autoclaved distilled water goes dormant because there are zero nutrients in the solution.

The notion that storing yeast under boiled tap water is better for the culture than storing it under green beer is a amateur brewing myth that is not supported by science. Here's why storing yeast under boiled tap water is not a smart thing to do. First off, as stated above boiled water is not sterile. Spores survive 212F/100C moist heat. Secondly, yeast own a medium by consuming all of the dissolved oxygen, lowering the pH, and producing ethanol, which is toxic to most microflora. Replacing green beer with boiled tap water raises the pH of the culture and removes the ethanol while possibly introducing spores, which can now germinate because we have removed the culture's force field. Maintaining a yeast culture in liquid form is about making trade-offs. It is almost always better to trade viability for purity than it is to trade purity for viability.

With that said, a very good, very stable, and relatively easy to master long-term storage method is available to amateur brewers; namely, storage on agar slants. I have pretty much brewed with home cultured yeast since I made my fourth batch of beer over twenty years ago. I maintained several cultures on agar slants for over ten years. The only reason why these cultures did last longer is because I took an extended hiatus from the hobby. Every amateur brewer who is willing apply himself/herself can learn how to maintain and use slanted yeast. Heck, if Denny Conn had never learned how to use slanted yeast, there would be no Wyeast 1450 today. Wyeast 1450 was originally distributed on slant by a company called Brewer's Resource. It was a culture known as Brewtek CL-50 California Pub Brewery Ale. Brewtek was the brainchild of Dr. Maribeth Raines. Maribeth taught an entire generation of amateur brewers how to plate and slant yeast with her yeast culturing kit and pamphlet.
Thanks for clarifying that boiled water is not sterile. Is there an article to read to support this? I would like to look into it. So, the distilled water that can be purchased at the local store couldnt this be used instead of boiled water as its distilled?

Im probably going to have to re-read what you posted before and read again. I just want to understand love anything about beer!
 

eluterio

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I would highly recommend it to any level of brewer. I am still learning myself but this is one easy step to build up a readily diverse supply of yeast and save money doing it :D
Im still going to attempt this and store under boiled RO water. I do comps so it will be interesting to see how my beers rate over my previous batches.
 

finsfan

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IDK about all the scientific facts about storing under water but I have been doing it for months and it works fine for me. Im sure plenty of other people do it as well. If it is this big of an issue I would start another thread to inform the rest of HBT about this mis-practice. I, however, will continue to do what has been working for me. In light of this information tho, I will keep one jar under the starter wort and see how it does since it will be months before I use it again. If it goes bad, you owe me new 1098 EAZ :D
 

EarlyAmateurZymurgist

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So im a bit confused.

EarlyAmateurZymurgist said this (Under no circumstance should one dilute a yeast culture with boiled tap water. Storing yeast under boiled tap water is actually bad for the culture)

However, while you continue to read his post it reads what finfan highlighted. Sterile distilled water. Is'nt this the same as boling water to get it to become sterile? Boiling off oxygen and bacteria therefore, making it sterile?


Sorry, I dont know how to quote each paragraph.
Boiled water is not sterile. Spores are not killed by 212F/100C moist heat. One has to raise the temperature of a liquid to 250F/121C in order to render it sterile. In order to raise the temperature of a liquid to 250F, we have to increase the atmospheric pressure under which it is heated because water boils at 212F/100C at 14.3 pounds per square inch (normal atmospheric pressure at sea level). Raising atmospheric pressure to 15 pounds per square inch above normal atmospheric pressure delays boiling until 250F/100C is reached. At 250F/121C, everything is killed, including spores. The process of subjecting a liquid to 250F/100C heat at 15 pounds per square inch is known in science as "autoclaving." laypersons refer to the process as "pressure cooking."
 

finsfan

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Boiled water is not sterile. Spores are not killed by 212F/100C moist heat. One has to raise the temperature of a liquid to 250F/121C in order to render it sterile. In order to raise the temperature of a liquid to 250F, we have to increase the atmospheric pressure under which it is heated because water boils at 212F/100C at 14.3 pounds per square inch (normal atmospheric pressure at sea level). Raising atmospheric pressure to 15 pounds per square inch delays boiling until 250F/100C is reached. At 250F/121C, everything is killed, including spores. The process of subjecting a liquid to 250F/100C heat at 15 pounds per square inch is known in science as "autoclaving." laypersons refer to the process as "pressure cooking."
Not to try to argue by any means but why then do we boil wort to make beer sterile or even boil wort to make starters if it only gets to 212*? I thought the point of boiling that starter wort was to sterilize it for contact with the yeast?
 

CA_Mouse

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I generally build a starter twice the size of what I need. I pour half into a sterilized mason jar, add a lid that has been boiled and sanitized and then vacuum seal the jar. Pulling the air out and leaving the starter wort seems to keep my yeast healthy for months. I just brewed a Belgian Golden Strong with yeast that I have had stored for 2 months. I did a 2 liter starter, decanted the 2 month old beer off the yeast and added it to the starter, cold crashed it for a week and decanted the starter work off and pitched into my 1.078 Belgian. The yeast was nice and clean and took off so well I had to move from an airlock to a blow off tube. 3 days later and it is still thumping away.
 

EarlyAmateurZymurgist

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IDK about all the scientific facts about storing under water but I have been doing it for months and it works fine for me. Im sure plenty of other people do it as well. If it is this big of an issue I would start another thread to inform the rest of HBT about this mis-practice. I, however, will continue to do what has been working for me. In light of this information tho, I will keep one jar under the starter wort and see how it does since it will be months before I use it again. If it goes bad, you owe me new 1098 EAZ :D
I will make a deal with you. If you learn how to work with slanted yeast, I will give you a couple of brewery cultures that you cannot acquire from the major yeast suppliers. These cultures are all isolates that I plated. Fair enough?

Here's a photo of one of the yeast cultures that you will receive on slant. The colonies in the red rectangle are each the offspring of single yeast cells; therefore, they are single-cell isolates (a.k.a. pure cultures). The slanted yeast culture that you will receive was grown from this plate.

 

EarlyAmateurZymurgist

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Not to try to argue by any means but why then do we boil wort to make beer sterile or even boil wort to make starters if it only gets to 212*? I thought the point of boiling that starter wort was to sterilize it for contact with the yeast?
Boiling wort does not render it sterile. What it does is kill everything, but spores, which do not have a the opportunity to germinate because the culture rapidly consumes the available oxygen, lowers the pH, and produces ethanol. Aerobic microflora cannot start because of the lack of oxygen. Microflora that are pH sensitive are stopped in their tracks. Finally, ethanol is toxic to almost all microflora.
 

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I will make a deal with you. If you learn how to work with slanted yeast, I will give you a couple of brewery cultures that you cannot acquire from the major yeast suppliers. These cultures are all isolates that I plated. Fair enough?

Here's a photo of one of the yeast cultures that you will receive on slant. The colonies in the red rectangle are each the offspring of single yeast cells; therefore, they are single-cell isolates (a.k.a. pure cultures). The slanted yeast culture that you will receive was grown from this plate.

If by working with if you mean stepping it up and using it, that can be done :D

Boiling wort does not render it sterile. What it does is kill everything, but spores, which do not have a the opportunity to germinate because the culture rapidly consumes the available oxygen, lowers the pH, and produces ethanol. Aerobic microflora cannot start because of the lack of oxygen. Microflora that are pH sensitive are stopped in their tracks. Finally, ethanol is toxic to almost all microflora.
So leaving ranched yeast on starter wort for a year isnt going to hurt it but leaving it on water will?
 
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ted464

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It pretty much is. It will always be 1st gen if you dont wash it. The best part is you roughly know how many cells you have each time. For instance, friday I made a starter that was 1600 ML that totalled 280 billion cells. I only needed 230 billion so I poured off the extra (285ML) to get my 230 bil cells and was left with 50 billion cells to keep. Normally I have around 100-150bil cells to save but I didnt make a big enough starter. Use yeastcalc.com and this thread to get the details.

https://www.homebrewtalk.com/entries/yeast-harvesting-novel-approach.html
I have never seen this technique, nice!
 

EarlyAmateurZymurgist

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If by working with if you mean stepping it up and using it, that can be done :D



So leaving ranched yeast on starter wort for a year isnt going to hurt it but leaving it on water will?
Neither medium is optimal for long-term yeast storage. However, if given a choice between the two, green beer with a little trub thrown in for good measure is the preferred medium. Ideally, if one wants to keep a liquid culture alive for an extended period of time, one should periodically decant the supernatant (the clear liquid above the culture) and replace it with fresh bitter wort in the 1.020 to 1.030 gravity range.
 

mtnagel

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Neither medium is optimal for long-term yeast storage. However, if given a choice between the two, green beer with a little trub thrown in for good measure is the preferred medium. Ideally, if one wants to keep a liquid culture alive for an extended period of time, one should periodically decant the supernatant (the clear liquid above the culture) and replace it with fresh bitter wort in the 1.020 to 1.030 gravity range.
Great thread. Learning a lot. I've also been saving a portion of the starter for a later batch and it's been working great. But I've also been storing it under boiled water (usually less than 50% of the volume is boiled water).

Question about this bitter wort though. By bitter, do you mean hops are added? If so, why? And if you are adding 1.020 OG wort to yeast, won't it ferment? Wouldn't I need an airlock or something other than a mason jar, which could explode from the CO2 generated?
 

eluterio

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Neither medium is optimal for long-term yeast storage. However, if given a choice between the two, green beer with a little trub thrown in for good measure is the preferred medium. Ideally, if one wants to keep a liquid culture alive for an extended period of time, one should periodically decant the supernatant (the clear liquid above the culture) and replace it with fresh bitter wort in the 1.020 to 1.030 gravity range.
Wow, EAZ thanks for the educational tutorial on this stuff its outstanding. I wish I had the means to answer or do what you require to get a hold of the yeast culture. Really sad note is I would have no idea what the hell to do with it if I did! If you didnt live so far away I would love to sit down and be educated!

From reading all of these post it would seem to be good practice, according to EAZ, you can make a huge starter keep x amount as is not to wash or use "Boiled Water" let it sit for a month or so. If you brew using different yeast like I do you can replace the old wort with fresh new wort to prolong live.

I use about 3 different yeast for now for different styles, Im just learning to brew to styles, I should be able to use method to last me awhile.

Please if im wrong let me know.
 

eluterio

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Great thread. Learning a lot. I've also been saving a portion of the starter for a later batch and it's been working great. But I've also been storing it under boiled water (usually less than 50% of the volume is boiled water).

Question about this bitter wort though. By bitter, do you mean hops are added? If so, why? And if you are adding 1.020 OG wort to yeast, won't it ferment? Wouldn't I need an airlock or something other than a mason jar, which could explode from the CO2 generated?
I might be able to answer using why bitter, I think the hops play a part in this but I dont know for sure.

Just speaking without knowledge here but I would assume why no airlock is the fact you would be storing it at cold temps. If using an ale yeast it would go or stay dormant, however, using a lager yeast I would assume some fermentation would happen and i would again assume opening/losen the lid for the first few days would help with the build up. Now im just going off of what I know about yeast in general.

I have to agree with you about this thread Im actually excited to learn more.
 

EarlyAmateurZymurgist

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Question about this bitter wort though. By bitter, do you mean hops are added?
Yes

If so, why?
Hops suppress the growth of wild microflora.

And if you are adding 1.020 OG wort to yeast, won't it ferment? Wouldn't I need an airlock or something other than a mason jar, which could explode from the CO2 generated?
Yes, that's why it is not wise to store cropped yeast in a sealed Mason jar. I use 500ml Erlenmeyer flasks with #7 stoppers and airlocks for cropped yeast storage. Contrary to the pseduoscience that is passed off as real science on most home brewing websites, yeast cells need a food source or they will begin to die. Storing yeast under boiled water does not prevent cell death. Periodically, decanting the supernatant and adding fresh bitter wort restarts the culture.

“In the stationary phase, the accumulated yeast biomass remains relatively constant and the specific growth rate (μ) returns to zero. After a prolonged periods in the stationary phase, yeasts may die or autolyse. This in turn may influence the continued growth and survival of the residual yeast cells.”

Walker, Graeme. Yeast Physiology and Biotechnology. Wiley
 

eluterio

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Yes



Hops suppress the growth of wild microflora.



Yes, that's why it is not wise to store cropped yeast in a sealed Mason jar. I use 500ml Erlenmeyer flasks with a #7 stopper and an airlock for cropped yeast storage. Contrary to the pseduoscience that is passed off as real science on most home brewing websites, yeast cells need a food source or they will begin to die. Storing yeast under boiled water does not prevent cell death. Periodically, decanting the supernatant and adding fresh bitter wort restarts the culture.

“In the stationary phase, the accumulated yeast biomass remains relatively constant and the specific growth rate (μ) returns to zero. After a prolonged periods in the stationary phase, yeasts may die or autolyse. This in turn may influence the continued growth and survival of the residual yeast cells.”

Walker, Graeme. Yeast Physiology and Biotechnology. Wiley
Thanks again for the insight.

So should I just toss out the washed yeast ive collected in recent weeks? I used boiled water to store but could replace with wort in the 1.020 range this week?

Whats your take on wyeast 1010 and 3068 for long term storage? Ive heard with wheat based yeast they dont last long in storage, is this true?
 

EarlyAmateurZymurgist

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Thanks again for the insight.

So should I just toss out the washed yeast ive collected in recent weeks? I used boiled water to store but could replace with wort in the 1.020 range this week?
I would not throw them out. I would select one crop from each distinct culture to maintain. As long as your are decanting the supernatant and adding new bitter wort periodically, the selected cultures should continue to produce good beer. Plus, sooner or later, you will catch the culturing bug and eventually learn how to plate yeast. Learning how to plate yeast for "singles" opens up an entirely different world--a world in which one can take a culture and purify it. That's what I do when I culture yeast from a bottle or receive a brewery crop. All of the yeast cultures in my bank have gone through single-cell isolation before being transferred to slant.

Whats your take on wyeast 1010 and 3068 for long term storage? Ive heard with wheat based yeast they dont last long in storage, is this true?
Some yeast strains are hardier than others. However, like all living things, yeast cultures are sensitive to their environment, and no two amateur brewers have the same environment. There is a saying in engineering (and computer science) that engineering = theory + practice. The same can be said about yeast management. We use science to get us on the page, and practice to find practical ways to use the science.
 
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