Yeast Slurry/Pitching on Yeast Cake/Washing yeast

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eluterio

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I have two different Wyeast 1010 and 3068. I made one american wheat and the other a German wheat. My intentions were to pitch on the yeast cake with a rye/2row on the 1010 and 3068 tomorrow. Long story short I had to american into another bucket due to broken spigot that cause me to lose 1 gallon of beer or more.

1010: In reading here on HBT I saw support for pitching on yeast cakes and not to. In part of my reading someone said sorry all i know his name is BOB jut to get a ss scoop and scoop it out instead of pitching on yeast cake. Since i had a broken spigot I have no choice but to scoop this yeast out. I did so and collected everything at the bottom of the bucket, hops, trub, yeast, and beer. Its settling right now and I have total 1 qt mason jar, and 8 z mason jar full. I can see the yeast still burping but no matter im still brewing tomorrow and pitching it.

Question: I used Mr Malty and saw that for a 1.052 I need 98 ml of yeast. I saw somewhere Mr. Malty was designed for when you wash the yeast. What amount do I do for yeast slurry?

For argument sake If its 100ml I need, should I rinse the rest as like ive seen on youtube and read here and store or can I just decant the slurry and store it for long term?

I am going to still poor wort on yeast cake on the 3068 then when i keg ill harvest that.

Im sure i have more questions but i have a screaming child that i must tend to now any advice would be most appreciated.
 
You should rinse it beofre using it. Add boiled and cooled water to your leftover yeast/trub mixture, set it in the refrigerator, let it settle for a few minutes, pour off the creamy white yeast into a new jar. Then estimate how much yeast you have in that jar after it has settled in the fridge and pitch according to mrmalty. That will be the way to pitch the right amount.
 
I did boil up some jars of water im prepared to do this set you mentioned however, me being a new to this why couldnt I pitch 100ml of the slurry that I pulled from the yeast cake? Are the concerns the yeast has too much trub in it and would add other stuff into the new batch?
 
You don't need to rinse it if you are going to use it relatively quickly (the next day is quickly). I've pitched the yeast cake that I stored in the fridge for a week and just accounted for some loss in viability. Worked great.

As for how much, you can use Mr Malty's calculator. Make sure to use the "repitching from slurry tab". You can change the "yeast concentration" slider. In Bob's "why not to pitch on a yeast cake" thread, he says you will have 1 billion/ml, but you can see that Mr Malty calls that a thin slurry. I assuming your's is thicker than "thin"? Mine always are. So you can move that to right. Or if you just keep the defaults, it will tell you to pitch 94 ml, so I'd probably go for that. If you're slurry is thicker, you will be overpitching, but I've heard that is better than underpitching. Good luck and let us know how it goes.
 
Thanks mtnagel for the info this was helpful. Ill go ahead and pitch the 100ml. Should I rinse the rest and store?
 
If you want to keep it for longer term storage (> a week or so), then yes.

Personally, I've started harvesting from starter. I think it's less work (just make a bigger starter, which you are already making anyway), you get cleaner yeast (no hops) and it doesn't really increase the generation count like a full fermentation would.

https://www.homebrewtalk.com/entries/yeast-harvesting-novel-approach.html
 
So im looking at my yeast and end up decanting the slurry and now have 600ml. I have a question on mr. malty how can you tell if you have a thin or thick slury. The difference between think and thin is 100ml, roughly. Ill probably pitch the 200 then rinse out the rest and store. And just to be clear im rounding up just to make it easy for my explanation. Ill probably be closer to the actual amount that Mr. Malty is asking for. Thanks
 
This is what Jamil says about that here:
This setting allows you to adjust for how thick a slurry you're measuring. If you've ever seen the yeast packed hard into the bottom of a White Labs vial, that is Thick Yeast at 4.5 billion cells per ml. When you harvest a yeast slurry and it has settled for a few hours, that is a thin slurry. Usually, most homebrewers will let their yeast settle for a few days in the fridge between one batch and the next. When you do, you'll notice the yeast has settled a bit and is sort of jelly-like. That is the default setting on the calculator. You'll need to estimate from there for other yeast thickness, but what is most important is keeping track of what you pitched and the results you get from the beer. If you need to adjust up or down, that is OK, just keep track of how you do things each time.

Once you've determined how much yeast you have in the container, you can shake the container along with any liquid to loosen up the yeast. If you determine there is 200 ml of yeast solids in the container and you want to pitch 100 ml. Shake the container to break up the yeast and then pour 1/2 of this very loose yeast slurry into your beer.
 
Contrary to what you will read on this forum, rinsing yeast with boiled water is a completely unnecessary step. You can repitch 100 to 250mls of slurry directly from the crop without fear of ruining your batch.
 
Contrary to what you will read on this forum, rinsing yeast with boiled water is a completely unnecessary step. You can repitch 100 to 250mls of slurry directly from the crop without fear of ruining your batch.
What I've seen is that rinsing is unnecessary when you are going to reuse the yeast cake within a week or so.

Just look at MrMalty's calculator. When you use the liquid yeast tab, if you use 1 month ago, the viability is 74%. But when you use the repitching tab, the viability drops to 43%. So that's why it's recommended that for longer term storage, you'd want to rinse, but if you are going to use it quickly, rinsing isn't necessary.
 
What I've seen is that rinsing is unnecessary when you are going to reuse the yeast cake within a week or so.

Just look at MrMalty's calculator. When you use the liquid yeast tab, if you use 1 month ago, the viability is 74%. But when you use the repitching tab, the viability drops to 43%. So that's why it's recommended that for longer term storage, you'd want to rinse, but if you are going to use it quickly, rinsing isn't necessary.

There's home brewing science and then there is REAL science. Yeast rinsing is home brewing voodoo that is not supported by peer-reviewed science. No professional brewer rinses his/her pitching yeast with boiled water. One has to keep in mind that the ethanol that is limiting the viability of the culture is also protecting it from infection. Rinsing yeast with boiled water raises the pH of the culture and removes the ethanol that is protecting it from wild microflora infection while possibly introducing spores, which are not killed at 212F/100C. A yeast culture takes over a batch of wort by consuming all of the dissolved oxygen, lowering the pH, and producing ethanol. We remove a cropped yeast culture's force field when we replace the green beer with water.

The proper way to store yeast for the long term is on agar slants or via cryopreservation. Yeast cultures will remain viable on agar slants for up to two years in a normal refrigerator before they will need to be subcultured (a loopful of yeast is aseptically transferred to new "blank" slant). One can store cultures almost indefinitely via cryopreservation at -80C. However, few of us can afford to kept a liquid nitrogen cooled freezer in our homes; therefore, those who wish to use cryopreservation at home will need to be happy with shorter time periods.

Maintaining yeast on agar slants is not rocket science (I have maintained cultures for up to ten years on agar slants). It was not uncommon for advanced amateur brewers to maintain a bank of yeast cultures on agar slants in the nineties. The culture that became Denny's Favorite 50 was originally distributed on agar slant by a company called Brewer's Resource. It was called Brewtek CL-50 California Pub Brewery Ale (my favorite Brewtek culture was CL-170 Classic British Ale). I have little doubt that Maribeth Raines' yeast culturing pamphlet is stored someone on the Internet (Brewtek was Maribeth's company). Maribeth is the godmother of yeast culturing and management within the amateur brewing community. Her pamphlet taught an entire generation of amateur brewers how to plate and slant yeast.

Here are a couple of photos that I took when I prepared a batch of slants and plates a few months ago:

Slants

slants_zpsd8559e74.jpg


Properly prepared plates

plates_zpsfb5c4940.jpg



Here's a plate that I used to streak for "singles" (the culture was grown from a commercially produced bottle-conditioned beer):

PlatedYeast_zps10c1ab8c.jpg


The yeast colonies in the red rectangle are pure-cultures. Each colony is composed entirely of the offspring of a single yeast cell. The colonies in the red rectangle were transferred to slants using aseptic transfer technique. Once purified via single-cell isolation, a culture can be transferred from slant to slant without plating. Yeast can be propagated from a slant using a sterile loop or by pouring few milliliters of absolutely sterile (a.k.a. autoclaved or pressure cooked) wort into the slant, capping the slant, shaking, and using the wort in the slant to inoculate 20 to 40mls of absolutely sterile wort.
 
No professional brewer rinses his/her pitching yeast with boiled water.
Well they also brew a lot more often than we do. I reuse yeast slurry like (I assume) they do when I'm using the same yeast back to back.

Maintaining yeast on agar slants is not rocket science (I have maintained cultures for up to ten years on agar slants). It was not uncommon for advanced amateur brewers to maintain a bank of yeast cultures on agar slants in the nineties.
I never really looked into it, but you're right, maintaining yeast on agar slants isn't *that* difficult, but I would say it's a bit more time consuming than rinsing yeast.

With that said, I don't even rinse yeast anymore. I've started harvesting from starters, which I'd say have a few advantages over rinsing yeast: it's easier (I just make a bigger starter and split off the yeast needed for brewing and the yeast I'm saving), you get cleaner yeast than rinsing and it (arguably) doesn't increase the generation like rinsing does.
 
When I picked up the slurry from the 1010 batch I had a qt and 8 oz. As I read and posted Mr. suggested 100ml roughly so I poured 100ml into a mason jar and waited until I was ready to pitch about 24 hours. I pitched the amount and im at 24 hours and nothing, getting worried. After a year of using smack packs ive never had to wait 24 hours.

I used the entire qt of 3068 and I had activity in 6 hours. I dont have the means to run to the LHBS and pick up yeast and dont have enough dme to make a starter besides waiting another 12 hours what else could I do??

Again I must stress first time so If I dump it im not too heart broken.
 
I assume you did all the normal stuff like oxygenate your wort thoroughly, pitch at the proper temperature and took proper sanitization steps, right?

And I assume the batch you harvested from had a normal and healthy fermentation, right?
 
I assume you did all the normal stuff like oxygenate your wort thoroughly, pitch at the proper temperature and took proper sanitization steps, right?

And I assume the batch you harvested from had a normal and healthy fermentation, right?

Correct on everything you said. Pitched at 66 F, oxygenated by shaking vigorously for 60 seconds and Im clean as hell. When I poured the 100ml I washed the rest of the yeast in the qt jar. I got 200 ml from that. I am not sure if enough DME to make a full 1 litter starter thoughts when I get home if its not bubbling to attempt to use the 200ml and make as much of a starter as possible and pitch it sa soon as I see signs of it working?

Again thanks for the info, I love learning about all this and for me sometime only way to learn is hands on.
 
Then not really sure what else to add. I've used harvested and pitched a portion of the yeast cake several times and had no issues.

Maybe you will be lucky and it will be bubbling away when you get home :) I've woken up after a brew day and went to check on it in the morning before work and nothing. But when I come home it's happily bubbling away.
 
We have lift off! Out was the air lock I had not enough star san in it the co 2 was coming out but no bubbles. Fully filled the air lock and pesto!
 
We have lift off! Out was the air lock I had not enough star san in it the co 2 was coming out but no bubbles. Fully filled the air lock and pesto!
 
You're so happy you had to tell us twice :)

Glad it's working for you. I was pretty sure it was going to be fine.

Stupid phone posted it twice. Thanks I was worried it took about 36 hours for it to show life but probably closer to 24 since the air lock wasnt completely full.
 

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