Mini-Mash Yeast Starter

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spanosspanos

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I did a little exercise/experiment today, and thought that it may be interesting to any new brewers out there like myself..
I've been studying and practicing calculating efficiencies, grain bills and target gravities by hand in an attempt to get a more in-depth understanding of how a recipe is designed. I'm also preparing to brew up my first saison within the next few days. And, I've been wanting to try my hand at a yeast starter for a while now, but as I currently only have dry yeast packets, and I haven't yet attempted brewing a "big" beer, I've been holding off. But, alas, my curiosity has once again gotten the better of me...and I did it anyway! Thing is, I don't have any DME, and I'm on a small island in Greece, so there is no running down to the neighborhood HBS :) What I do have is an ample supply of Maris Otter however, as well as plain old white sugar, and it occurred to me that I could create a recipe for a mini partial mash, and that would be an interesting challenge for calculation! So...here's what I got:

16oz Starter @ 1.040
90.5% Mash Efficiency
Maris (81 %Extract): 43.5 grams (~ 21.6 G-pts)
Sugar (100 %Extact): 24.5 grams (~ 18.4 G-pts)
Mangrove Jack M29 French Saison: 1 Packet (11.5 grams)

I brought 16oz of water to 150°F in a small sauce pot, and stirred in 44 grams of Maris Otter (my scale doesn't do 1/2's, so I rounded up). I then turned off the burner, covered the pot and let the mini-mash sit for 60min, after which I once again turned on the burner and raised the temp to 170°F and "mashed out". After straining the wort into a measuring cup, I added 2-3 ounces of water to bring the volume back up to 16oz, and took a gravity reading...1.022 (after adjusting for temp). Just a hair above my target, which I'm quite certain is due to having rounded up that 1/2 gram. Back into the pot to bring to a boil, I added the sugar and stirred to dissolve. Once a mild, simmering boil began to show, I felt that the wort had been sufficiently pasteurized, and I removed from the stove, poured into the measuring cup, added about 1-2 ounces of water (that I had previously boiled and cooled) to bring the wort back up to 16oz, and placed it in the freezer to bring it down to pitching temperature. Once that was all good, I took another gravity reading...1.042 (after adjusting for temp). Pretty darn on target!
I transferred the wort to a thoroughly cleaned and sanitized jar (nothing special, just a good 'ol jar I had in a cabinet), and sprinkled the yeast onto the surface of the wort. Once it fully rehydrated, I gave it a good swirl for about 2 minutes, placed the lid on top without securing it, and placed it in a cabinet in my kitchen. The yeast jumped into activity, and within an hour I could see signs of a krausen beginning to form! I plan on swirling it several times throughout the day for the next 2 or 3 days, and if all goes well with my timing, I should be neck deep into a brew day by Tuesday!

Thanks for reading all...if anyone has any thoughts, suggestions, questions or critiques please share! I've learned a LOT from the various topics, forums and of course awesome people here in HBT...I hope this starter tale has returned some of the energy back into the collective!

PS-everything I used (thermometer, jar, hydrometer, yeast pack, scissors etc.) was cleaned and sanitized throughout the process...Sanitize Sanitize Sanitize!!!

IMG_1535208651.520329.jpg
 
Thanks for your detailed write-up!
You've also got a wonderful view to make most everyone jealous!

You definitely need to look for a bigger jar to put your starter in. For a few reasons:
  • Without a stir plate, you may get explosive fermentation (krausen, foam) somewhere down the line, and you stand to lose more than half of what's in that jar to your kitchen cabinet/countertop.
  • Yeast needs oxygen to propagate, so intermittent shaking or swirling will incorporate more oxygen into your starter beer. Larger headspace allows for more air to be mixed in.
  • The lid should be on loosely, so air can circulate freely in and out as CO2 is being created. I think you're doing that. OK!
  • Most importantly, you need much more wort to grow yeast. Take a look at a yeast calculator such as HomeBrewDad's. Count on having at least 200 billion cells in that dry pouch of yeast. Age is pretty much insignificant when it comes to dry yeast as long as it was stored cool (refrigerator or freezer), and not stored in hot environments for long times. Even then, they are in dried form, and very much protected that way.
  • Your small jar with wort will somewhat revitalize (rejuvenate) your yeast, but "starters" are rarely needed or often urged against with dry yeasts, as they are dried and stored to have optimal characteristics and vitality (sterol reserves) upon pitching, either with or without re-hydration.
  • In comparison, for liquid yeasts, starters are pretty much mandatory, as their vitality goes down from the moment they get packaged while the cell count per pack is already lowish (~100 billion), dropping with each month of age.
A few notes:
Going through all that work, you could prepare much more starter wort and after boiling refrigerate in closed jars for a few weeks, perhaps longer. Or better yet, pressure can them for ultimate sterility and any time use.

Or brew a small batch of beer, harvest the yeast cake and brew bigger or stronger batches with those. Then harvest those yeast cakes (except from the very strong beers) and so on.

Or save some wort out when you brew a beer, to use for starters later. When saving wort, you need to pay attention to proper pasteurization and sanitation if stored for extended times.
 
And thank you for such a detailed reply! :) I really like the idea of pressure canning wort for future use... And I've been itching to attempt a harvest, but have been worried that I don't have enough, or large enough jars! So I guess I may have jumped the gun a bit on the starter (though it was at least partially an exercise to see if I could do the math by hand and hit the targets without brewing up a whole batch of beer).

That said, as I'm planning on brewing in a couple of days, do you think I need to increase the wort volume right away? Or might I get away with pitching what I've got, being that the cell count was already likely adequate for a 6 gallon brew....?

So far so good...as far as a mess in my cabinet goes! :) I've been checking on it and swirling frequently...I'll keep my fingers crossed!

PS-the view certainly makes for a pleasant brew!! [emoji295]️[emoji305][emoji41][emoji482]
 
Aside from 2 liter erlenmeyer flasks I also use 1/2 gallon (1.9 liter) glass pickle jars to make starters in. They even come in gallon size. Instead of stir plates I mostly use orbital (lab) shakers now, so I'm not bound to pure flat bottomed vessels to keep the stir bar in place, but it limits the volume in those flasks and jars to about 1.6 liter. I get tons of yeast growth.

Read some of the guidelines in the stickies and threads in the Yeast forum to inform yourself on yeast propagation. Some maybe a little outdated, like boiling wort in a glass erlenmeyer on a stove is a very firm no-no in my book. Use a (stainless) pot on the stove instead, chill in a sink or tub with cool water, then pour into your yeast propagation vessel, just like you did this one.

One thing you'll see, instead of using a loose lid, most of us use aluminum foil to (loosely) cover the mouth of the jar. The foil should go down about 2 inches, to prevent "bugs" from getting in.

One of my favorite yeast propagation methods is to brew a low gravity (session) beer (~3.5-4% alcohol) and use half (or more) of the yeast cake for a much larger beer (1.080+). That way you can drink good beer while the larger one is fermenting and conditioning slowly.

On a side note, I'm going to move this thread to the Fermentation & Yeast Forum, it really belongs there, and it'll get better exposure and hopeful more feedback there too.
 
Aside from 2 liter erlenmeyer flasks I also use 1/2 gallon (1.9 liter) glass pickle jars to make starters in. They even come in gallon size. Instead of stir plates I mostly use orbital (lab) shakers now, so I'm not bound to pure flat bottomed vessels to keep the stir bar in place, but it limits the volume in those flasks and jars to about 1.6 liter. I get tons of yeast growth.

Read some of the guidelines in the stickies and threads in the Yeast forum to inform yourself on yeast propagation. Some maybe a little outdated, like boiling wort in a glass erlenmeyer on a stove is a very firm no-no in my book. Use a (stainless) pot on the stove instead, chill in a sink or tub with cool water, then pour into your yeast propagation vessel, just like you did this one.

One thing you'll see, instead of using a loose lid, most of us use aluminum foil to (loosely) cover the mouth of the jar. The foil should go down about 2 inches, to prevent "bugs" from getting in.

One of my favorite yeast propagation methods is to brew a low gravity (session) beer (~3.5-4% alcohol) and use half (or more) of the yeast cake for a much larger beer (1.080+). That way you can drink good beer while the larger one is fermenting and conditioning slowly.

On a side note, I'm going to move this thread to the Fermentation & Yeast Forum, it really belongs there, and it'll get better exposure and hopeful more feedback there too.

Nice! Definitely gonna add the low gravity yeast cake to my to do list once I crack the ice on high gravity brews...which is surely soon to come. And it looks like I'll be saving my pocket change in the cookie jar for bit so I can invest in some more "proper" propagation hardware...
Thanks for moving the thread as well...I figured there would be a separate forum or topic, but must have passed it by while scanning through the options :)

Cheers bud! [emoji482]
 
Well....the party is a rockin! Even with such a small starter...now we wait for the only evidence that will matter...drinking it! [emoji482]
 
IMG_0801.jpg


Jumped right into activity within about 6 hours after pitching... This photo is at about 14hrs in...
 
I tried this once again, so I figured I'd do a quick write up...cause ya' know:..it's HomeBrewTalk! :)
My first attempt at this was for a few reasons, primarily as a practice and learning experience in writing out and calculating a recipe for weights and gravity without the help of software. However, I also don't currently have access to a LHBS, so DME and yeast nutrient are simply not happening. In my readings, I've frequently come across the info that the yeast we pitch feeds off of (among other things) the proteins and other compounds that are part of the mash. So...I thought, "If I do a mini-mash, then maybe I'll get all the good stuff the yeast will need for a solid starter...?". So I tried it. The first go was only 16oz., which I believe there is a large consensus that this is way too small. I gotta say though, I pitched it into a light saison, and the yeast seemed to be VERY happy... (I'm gonna bottle that beer tomorrow, so maybe I'll check back in here with a FG).
Anywho's, this time I did a quart (essentially simply doubling the numbers in the recipe above, although I went through the task of starting all the calculations over from scratch) and I used the yeast I washed off of a brew I bottled up last week (citra/mosaic dry-hopped pale). That was also my first attempt at washing yeast...so a whole lots of learning going on for me! (and a good amount of nerves as well! ;-). For the first several hours, I could only see that the yeast was settling out in the jar, and I was feeling pretty skeptical...but by about 12hrs..I saw some signs of foam floating on the top... By morning, or about 18hrs...crazy kreuzen!

I may or may not do this again, but I can certainly say that this was a great way to practice not only doing the math for the recipe (minus color and IBU), but it was also a great run-through of what is essentially a full brew day, with almost no cleanup, and way less time heating up and cooling things down... I even geeked out and did a 3 step mash for protein (120*-130*F for 15), Beta (145* for 15) and Alpha (155*F for 15); and then I did a mini batch sparge (165*-170*F for 15), which also gave me the opportunity to try some sparge volume calculations.
It all went well, hitting my mini-targets and such, learned a bit about absorption volume, and pitched the washed yeast into a tiny brew...
I'll be pitching this new starter into a brew I'm planning for this Friday...targeting a 1.080 strong ale....which I hope to help keep me warm this winter ;-) [emoji482]
 
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