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HoppyHaze

Home is where the fermentation is
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Hey everyone, I am hoping to get into yeast harvesting and starters because its pretty pricey and im hoping to do some more smaller batches.

I currently have been doing a swirl when I walk by method in a growler. I do not have a flask/stir plate. I would like to start overbuilding my starter and harvesting 100b yeasties for future batches, this seems way better than washing to me, however it looks like using the shaken not stirred method isn't really designed for overbuilding and the amount of DME for building a step up starter with just shake agitation would negate the cost savings.

I guess I am basically asking for overbuilding starters and not using tons of DME is my only option a stir plate? If that's a yes what DIY tutorial/equipment worked best and what size flask (or diy container) do yall recommend.

Thanks for the assist :hops:
 
Stirplates are the best option for making starters. Not only are they done faster (<24 hours in most cases) but you can make smaller starters to get the cell count. I've been known to do two, or three, step starters when the recipe needed more cells. Either from frozen yeast or older packages of yeast (months old).

Something else to think on. Using the stirplate means you [basically] get the starter going and walk away until it's done. I typically check on it sometime in the hours after I get it going (often either after lunch or dinner) and then several hours later. You learn what to look for to tell the starter is finished.

I'm using Proper starter cans (concentrate canned starter wort) these days because it makes the process easier. I get the needed cell count (or close enough) for the batches this way. When using yeast from a harvest, I'll pull a portion and do a 1L starter (on stirplate) a couple of days before brew day. It's finished within 24 hours, and then goes into the fridge for at least another 24 hours to settle. I decant most of the spent starter wort, leaving just enough to make a slurry. That goes into the yeast brink to get pushed into the conical.

Another item to keep in mind is when buying flasks. Get one that leaves 1L of head space for your starter size. I use my 2L flask for 1L starters. The 3L flask is used for up to 2L starters. I also use the 3L flask when doing more than one starter step for a batch. There's software/apps out there that will help you to figure that part out.

I can't imagine makin starters WITHOUT a stirplate and flask(s) at this point. Maybe, at some point, I'll get to use my 5L flasks. ;)
 
it looks like using the shaken not stirred method isn't really designed for overbuilding and the amount of DME for building a step up starter with just shake agitation would negate the cost savings.
Swirling on the countertop is "intermittent agitation," NOT the Shaken-not-Stirred method, which needs a whole different approach.
But S-n-S can be done by letting fresh air in, then shaking vigorously every 60' or so, creating as much foam as possible.
Do not use Fermcap-S with this method.

Yes, letting it ferment out mostly will not create optimal yeast growth. To entice optimal growth the starter needs to be fed oxygen continuously while driving off CO2. That way the yeast keeps replicating without going into fermentation mode.
 
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This is the stir plate I'm currently using. It replaced the Hanna I bought about a decade ago (that failed).
https://www.morebeer.com/products/compact-magnetic-stir-plate.htmlMoreBeer also has 2L and 3L flasks in stock. I get the foam stoppers from Northern Brewer since they are sized properly for the flasks. The ones MoreBeer sells are a bit too small. They barely stay in the openings, and can fall in far too easily. IME, you want ones that are large enough to have tension when inserted (you squeeze them to fit, they expand and won't move too easily).

BTW, the foam stoppers promote gas exchange without risking something going into the starter that you don't want. Like bugs.
 
Alright!

FWIW, don't boil the starter wort in the flask.
Use a stainless kitchen pot on the stove instead, and when done, close with a well fitting lid. Chill in the sink or a plastic tub.
Or use canned starter wort. ;) No boiling needed. Plus, if you have a GAS stove, you could put the flask on the burner. Do NOT try that with any kind of electric stove.
 
Thank you all, thanks for the link to the sponsor stir plate, that looks perfect for my needs. I appreciate all the advice on here, Im excited to add a new gadget and some more yeast possibilities :ban:
 
What I do is maintain strains in a jar in the fridge so when I need new yeast I pour off some of the cake into a starter and build up what I need for a batch and then add wort/DME to the origin jar. Then I can grow fresh yeast for the batch but also replenish the original culture without any risk of infection from putting yeast back in from a fermentation vessel. It doesn't matter how quickly the origin jar regrows so I don't worry about injecting oxygen or air into that jar beyond an initial aggressive shake (with the lid on) and then leave the lid ajar until fermentation winds down. Then back in the fridge it goes.
 
Alright!

FWIW, don't boil the starter wort in the flask.
Use a stainless kitchen pot on the stove instead, and when done, close with a well fitting lid. Chill in the sink or a plastic tub.
Why not boil in the flask?
 
I have read of them cracking on electric stoves but I’ve been boiling mine on my gas stove without issue for a few years. Maybe one day I’ll report back of the mess I’ve made. But I’ll likely continue to boil in the flask only because it makes me sleep better knowing it’s sanitized.

it does take awfully long to cool even in an ice bath though I will say that.
 
I don't have a stir plate, but I can see where in some cases it would be handy. I have been thinking of building one or two based on ideas from this video:

Yes, they're easy to build if you're handy or know someone who is.

A computer fan, wall wart, and a PWM (Pulse Width Modulation) module (eBay, AliExpress) and some sort of frame, box or platform is all you need. The PWM helps dialing in the right speed while still transferring enough power to spin. There are plenty of alternatives and better options, of course.
 
Try not to view it from a cost point of view. Fact is it can be done on the tightest budget. I make my own starter wort, which, although a lot cheaper for me than DME, it's actually better, imo. It looks and smells much nicer than DME and the yeast seem to grow better in fresh wort too. I just do a simple mini mash when I'm prepping dinner in the kitchen. (Obviously, it helps if you're an AG brewer and have base malt to hand, but otherwise a great way to get into AG.) I stopped using conical (Erlenmeyer) flasks years ago. There's really nothing special about them when it comes to culturing yeast. Continued use in microbiology has more to do with historical memes than anything else. They're often easily broken too and end up as expensive mistakes. I prefer Duran type lab bottles for culturing. They're much stronger and have screw caps too. Anyway, I think it's better to view managing your own yeast starters for the main benefit - being able to pitch the best possible yeast every time. You can't buy that. You have to prepare it yourself.

Harvesting and repitching within a few days (without needing a starter) is the most convenient way to pitch yeast at their best and cheapest - why breweries do it - but not necessarily an option for home brewers. I tend to binge brew and harvest/repitch for a few weeks or so. Here's a freshly harvested top-cropper (Yorkshire Square).

IMG_0391.JPG


It's like 'Rambo' looking for a jungle. Repitched straight away or within a few days of harvesting it's something else. 'Rambo' on a mission.
 
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Try not to view it from a cost point of view. Fact is it can be done on the tightest budget. I make my own starter wort, which, although a lot cheaper for me than DME, it's actually better, imo. It looks and smells much nicer than DME and the yeast seem to grow better in fresh wort too. I just do a simple mini mash when I'm prepping dinner in the kitchen. (Obviously, it helps if you're an AG brewer and have base malt to hand, but otherwise a great way to get into AG.) I stopped using conical (Erlenmeyer) flasks years ago. There's really nothing special about them when it comes to culturing yeast. Continued use in microbiology has more to do with historical memes than anything else. They're often easily broken too and end up as expensive mistakes. I prefer Duran type lab bottles for culturing. They're much stronger and have screw caps too. Anyway, I think it's better to view managing your own yeast starters for the main benefit - being able to pitch the best possible yeast every time. You can't buy that. You have to prepare it yourself.

Harvesting and repitching within a few days (without needing a starter) is the most convenient way to pitch yeast at their best and cheapest - why breweries do it - but not necessarily an option for home brewers. I tend to binge brew and harvest/repitch for a few weeks or so. Here's a freshly harvested top-cropper (Yorkshire Square).

View attachment 744742

It's like 'Rambo' looking for a jungle. Repitched straight away or within a few days of harvesting it's something else. 'Rambo' on a mission.
Can you tell me more about your mini mash process?
 
Try not to view it from a cost point of view. Fact is it can be done on the tightest budget. I make my own starter wort, which, although a lot cheaper for me than DME, it's actually better, imo. It looks and smells much nicer than DME and the yeast seem to grow better in fresh wort too. I just do a simple mini mash when I'm prepping dinner in the kitchen. (Obviously, it helps if you're an AG brewer and have base malt to hand, but otherwise a great way to get into AG.) I stopped using conical (Erlenmeyer) flasks years ago. There's really nothing special about them when it comes to culturing yeast. Continued use in microbiology has more to do with historical memes than anything else. They're often easily broken too and end up as expensive mistakes. I prefer Duran type lab bottles for culturing. They're much stronger and have screw caps too. Anyway, I think it's better to view managing your own yeast starters for the main benefit - being able to pitch the best possible yeast every time. You can't buy that. You have to prepare it yourself.

Harvesting and repitching within a few days (without needing a starter) is the most convenient way to pitch yeast at their best and cheapest - why breweries do it - but not necessarily an option for home brewers. I tend to binge brew and harvest/repitch for a few weeks or so. Here's a freshly harvested top-cropper (Yorkshire Square).

View attachment 744742

It's like 'Rambo' looking for a jungle. Repitched straight away or within a few days of harvesting it's something else. 'Rambo' on a mission.
I would also love to hear the process. Those Duran bottles look amazing! Thanks for all the advice this is great!
 
I can't imagine makin starters WITHOUT a stirplate and flask(s) at this point. Maybe, at some point, I'll get to use my 5L flasks. ;)

Brew more lagers!

Seriously though, I use a 5L almost as much as a 1L. Sometimes I wonder if I'm actually making a starter, or just brewing a 1 gallon batch. Come to think about it, I guess I'm really doing BOTH.
 
Brew more lagers!

Seriously though, I use a 5L almost as much as a 1L. Sometimes I wonder if I'm actually making a starter, or just brewing a 1 gallon batch. Come to think about it, I guess I'm really doing BOTH.
No desire to brew any lagers at this time. :p

IME, a 1L flask is too small. Especially since I never make a starter below 1L in size. Trying to make a 1L starter in a 1L flask is setting yourself up for a mess.
 
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About the only thing I use a 1L flask for is a viability starter from a previously frozen sample or boosting an out-of-date commercial yeast. 250ml of 1.020 SG wort, add 50 ml White Labs or thawed yeast sample, oxygenate, add a pinch of DAP and spin it at low speed for 24 hours to see if anybody wakes up. That's about it for the 1L flask.

If all goes well, decant whatever settled slurry there is into 1L of 1.020 SG starter wort in a 2L flask for 24 hours. Cold crash, decant, add 1L 1.040 SG wort into the same 2L flask, spin, decant, pitch. Don't know the cell count but it's gotta' be 1~2 B/ml at that point. Good to go for an ale.

For lagers I'll step it one more time with the decanted yeast into 2L of 1.040 SG wort in the 5L flask and spin it to high krausen. That will usually give me at least 300ml of dense slurry after cold crashing and decanting, so I'm guesstimating something between 200 billion and 400 billion cells of very viable yeast at that point.

The only reason I don't propagate lager yeast in a 3L flask is that I don't have one, and thought that, since size matters, the 5L one would look way cool in my brew area. I've since had a few propagations that were so vigorous that they would have spluged out the top of a 3L, so, mission success with that. Plus it does look way cool!
 
Can you tell me more about your mini mash process?
I would also love to hear the process. Those Duran bottles look amazing! Thanks for all the advice this is great!

It's just the simplest mash ever, on a small scale. A 4L (1.2 gallon?) pot, small nylon mash bag and candy thermometer. Water and a little pale malt. A very cute little BIAB. As it happens I'm doing one this weekend, to prep some yeast for my Christmas ales. I'll take a few pics of the process over the weekend and populate the thread.
 
It's just the simplest mash ever, on a small scale. A 4L (1.2 gallon?) pot, small nylon mash bag and candy thermometer. Water and a little pale malt. A very cute little BIAB. As it happens I'm doing one this weekend, to prep some yeast for my Christmas ales. I'll take a few pics of the process over the weekend and populate the thread.
Do you just dilute with distilled/ sanitized h20 to make your target gravity? Seems simple (and smart!).
 
Do you just dilute with distilled/ sanitized h20 to make your target gravity? Seems simple (and smart!).
I use boiled tap water to dilute. My tap water isn't far off distilled water, 'anaemic' minerally speaking, so I do treat it to get a 'general' profile, ensuring there are enough calcium ions for efficient enzyme activity. If I plan to store it in the fridge for days (or freeze it for weeks) I just dilute with water from the tap and simmer it with the lid on (to minimise evaporation/keep it at 1.040) for 15-20 minutes then pour into hot oven-sterilised lab bottles. This produces super sanitised, if not sterile, wort suitable for storing. It's always handy to have some available. I'll do something similar with any spare wort on brew day - simmer it next morning then store it.
 
IMG_0531.JPG

I used 800g Maris Otter (Warminster Low Colour) for no particular reason, just that the sack was open. Some brewing salts (to get a 'general' profile) and 3.5L tap water. The nylon grain bag fits nicely into steamer that came with the 4L pot (Ikea, I think).

Mashed in:

IMG_0533.JPG


With the lid just cracked, I get a fairly stable mash temperature on the lowest hob setting. Mashed at 62℃ for about 75 minutes. As it's starter wort, I want it very fermentable, hence to low mash temp. This might be partly why yeast seem to grow better in fresh wort vs DME? More nutrients too, I guess.

IMG_0537.JPG


Boiled for about 45 minutes outside on the grill:

IMG_0545.JPG


I add a pitch of yeast nutrient before topping up.

IMG_0546.JPG


Topped back up using boiling water and gave it a good stir at flame out:

IMG_0547.JPG


Lid on and being left ('no chill') until tomorrow morning.

IMG_0548.JPG


Obviously, if required sooner it can be chilled.
 
Is the bag you use a paint strainer from the hardware store?
Looks like it's Swiss Voile. I used to have my wife sew some bags back in the day when I used to BIAB. The material is a bit pricey at the fabric store, but it cleans and sanitizes easily, strains exceedingly well, is light weight but extremely strong, and is temperature stable to 350F IIRC. Great stuff.
 
Looks like it's Swiss Voile. I used to have my wife sew some bags back in the day when I use to BIAB. The material is a bit pricey at the fabric store, but it cleans and sanitizes easily, strains exceedingly well, is light weight but extremely strong, and is temperature stable to 350F IIRC. Great stuff.
It does do a great job. I got a couple a few years ago and I'm still on the 1st one. In fact, I can't even remember where the 2nd one is now.
 
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I used 800g Maris Otter (Warminster Low Colour) for no particular reason, just that the sack was open. Some brewing salts (to get a 'general' profile) and 3.5L tap water. The nylon grain bag fits nicely into steamer that came with the 4L pot (Ikea, I think).

Mashed in:



With the lid just cracked, I get a fairly stable mash temperature on the lowest hob setting. Mashed at 62℃ for about 75 minutes. As it's starter wort, I want it very fermentable, hence to low mash temp. This might be partly why yeast seem to grow better in fresh wort vs DME? More nutrients too, I guess.



Boiled for about 45 minutes outside on the grill:



I add a pitch of yeast nutrient before topping up.



Topped back up using boiling water and gave it a good stir at flame out:



Lid on and being left ('no chill') until tomorrow morning.


Obviously, if required sooner it can be chilled.

When I make a big batch of starter wort I boil it for a few minutes to get past the hot break, but not anywhere near 45 minutes.
Any particular reason you boil so long?
 
When I make a big batch of starter wort I boil it for a few minutes to get past the hot break, but not anywhere near 45 minutes.
Any particular reason you boil so long?
Yes, I like to ensure the starter wort is sanitary. If I'm culturing from a loop's worth of yeast or stepping up from there (from 10ml) to 100ml, I'll simmer with the lid on the following day, a double boil, to kill any spores that germinate after the 1st boil. Malted barley is very far from sanitary. I'd boil for at least 30 minutes here, but I'm not working to a tight procedure. The boil might be longer if I'm busy doing other things. It doesn't matter, because I'll top back up anyway.
 
Yes, I like to ensure the starter wort is sanitary. If I'm culturing from a loop's worth of yeast or stepping up from there (from 10ml) to 100ml, I'll simmer with the lid on the following day, a double boil, to kill any spores that germinate after the 1st boil. Malted barley is very far from sanitary. I'd boil for at least 30 minutes here, but I'm not working to a tight procedure. The boil might be longer if I'm busy doing other things. It doesn't matter, because I'll top back up anyway.

I see. If you're working from small amounts of yeast, any contamination can be a problem.

I pressure can mine afterwards so that it is shelf stable.
 
After diluting to get 1.040 wort I managed to get 3.5L.

IMG_0550.JPG


Left about 300ml trubby crap in the pot.

IMG_0552.JPG


Going back to the OP, which I feel I've hijacked a bit, any starter is better than no starter when using wet yeast, but all methods only work well when healthy, viable yeast are used. The simplest method involving just leaving it and swirling it occasionally, when you pass it, works fine. It takes 4 days or so and the cell count is going to be a little lower, but it works. As already noted, a stir plate, my method of choice, is the most efficient method for culturing yeast. It only needs to keep the yeast in suspension where they freely access sugars and other nutrients. An Atlantic style maelstrom isn't needed, regardless how impressive it might look. Two very important factors to consider when culturing yeast starters. Keep it warm, up to 30℃ is fine. The warmer it is the higher the metabolic rate. Remember it's a yeast culture not a fermentation. And aerate the starter wort. Yeast need O2 to bud efficiently. Give it a good shake before adding the yeast. If you have pure O2, use it. Pure O2 can take even a stir plate to a whole new level.

If you have a yeast pack that's passed its best and maybe not sufficiently viable for a single step starter, start with a mini starter of about 10ml wort in a 30ml vial. (Ideally, the wort at this step and the next is sterile, at least double boiled, as described earlier.)

IMG_0553.JPG


Just add a tiny drop of the yeast slurry, no bigger than a match head. Leave for at least 48 hours, until yeast sediment forms (like above). Step up to 100ml and leave it for another 48 hours. Repeat, 500ml then 2500ml. You're guaranteed to have significantly more viable yeast cells than had you pitched the whole pack in 2500ml. The aim really is to maximise the probability of a successful fermentation, rather than take chances with the unknown.
 
Great summation. The only tweak I might add would be in propagating the first step of a sample of questionable viability would be to use a wort with a gravity of about 1.020, or half strength, then use 1.040 SG worts in subsequent propagation steps. Actually I believe that a wort of 1.038 has been shown to be the optimum gravity for yeast propagation, but lower viability starters benefit from a less stressful "jump start" with weaker wort. Think of it as nursing a sick colony back to health with thin soup, then fattening it to consume a banquet.
 
Going back to the OP, which I feel I've hijacked a bit,
That was a welcomed hijack. This has been incredibly helpful, I just did my first starter on a stir plate and the lag time was greatly reduced when I pitched it. In fact i'm not sure how quick it took because I pitched at bedtime and it was bubbling away by morning. I plan on creating your mini mash for future starters. Thank you! :ban:
 
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