Coldbreak Brewing Giveaway - Open to All!

Home Brew Forums > Home Brewing Beer > Fermentation & Yeast > Reclaiming Pacman Yeast - Stir Plate or No Stir Plate?
Reply
 
Thread Tools
Old 10-09-2013, 04:40 PM   #1
Zabuza
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2012
Posts: 172
Liked 4 Times on 4 Posts
Likes Given: 9

Default Reclaiming Pacman Yeast - Stir Plate or No Stir Plate?

So I made a 250 ml starter of 1.040 wort, and added the dregs from 4 rogue bombers (two were chocolate stout, 2 were Santa's helper ale or whatever). Now I'm wondering: should I let it sit and ferment on its own, or should I throw it on a stir plate? Seems like a completely sanitary environment would be beneficial since I'm using tired, old, and weak dregs (they won't have to compete with other organisms), but then it seems like a stir plate would really help get them going and replicate faster (although it does obviously expose them to competing organisms).

Thoughts? I searched and found people suggesting both ways for the first step in this process.


Zabuza is offline
 
Reply With Quote
Old 10-09-2013, 07:10 PM   #2
bja
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2007
Location: Pittsburgh
Posts: 1,974
Liked 151 Times on 113 Posts

Default

Quote:
Originally Posted by Zabuza View Post
but then it seems like a stir plate would really help get them going and replicate faster (although it does obviously expose them to competing organisms).
How does it expose them to competing organisms?


__________________
____________________________________________

I know it just wouldn't be right to kill all the stupid people that we meet, but do you think it would be appropriate to just remove all of the warning labels and let nature take its course?

Life is tough. It's tougher if you're stupid.
bja is offline
 
Reply With Quote
Old 10-09-2013, 07:28 PM   #3
Denny
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2005
Location: Eugene OR
Posts: 4,380
Liked 467 Times on 348 Posts
Likes Given: 583

Default

Quote:
Originally Posted by Zabuza View Post
So I made a 250 ml starter of 1.040 wort, and added the dregs from 4 rogue bombers (two were chocolate stout, 2 were Santa's helper ale or whatever). Now I'm wondering: should I let it sit and ferment on its own, or should I throw it on a stir plate? Seems like a completely sanitary environment would be beneficial since I'm using tired, old, and weak dregs (they won't have to compete with other organisms), but then it seems like a stir plate would really help get them going and replicate faster (although it does obviously expose them to competing organisms).

Thoughts? I searched and found people suggesting both ways for the first step in this process.
I've done it both ways. Stir plate is faster, other than that it doesn't matter.
__________________
Life begins at 60....1.060, that is!

www.dennybrew.com

http://www.experimentalbrew.com - the website for the book "Experimental Homebrewing"...coming Nov. 2014
Denny is offline
 
Reply With Quote
Old 10-09-2013, 11:26 PM   #4
Zabuza
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2012
Posts: 172
Liked 4 Times on 4 Posts
Likes Given: 9

Default

Quote:
Originally Posted by bja
How does it expose them to competing organisms?
Stir plate starters are left open to the air, with no airlock, that the agitated wort can pick up oxygen from the air. They also, however, pick up whatever else is in the air...that's why it's commonly recommended that you decant off the majority of the liquid and use (primarily) the slurry at bottom.

Thanks for the replies, you guys. I'm still worried that microorganism exposure with such a small amount of pitched yeast could be problematic, but I guess I'm overly concerned.
Zabuza is offline
 
Reply With Quote
Old 10-09-2013, 11:35 PM   #5
b-boy
16%er
HBT_LIFETIMESUPPORTER.png
Feedback Score: 5 reviews
 
b-boy's Avatar
Recipes 
 
Join Date: Jun 2011
Location: The Frozen Tundra, NY
Posts: 3,604
Liked 863 Times on 598 Posts
Likes Given: 265

Default

I wouldn't worry about it. Just sanitize your flask, and your stir bar and you should be fine. Put a piece of sanitized foil loosely on top of the flask. I'd say there's more of a chance of contamination from collecting the dregs than from your stir plate.
__________________
Never underestimate the potential of someone who refuses to act their age.
b-boy is offline
 
Reply With Quote
Old 10-09-2013, 11:36 PM   #6
Denny
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2005
Location: Eugene OR
Posts: 4,380
Liked 467 Times on 348 Posts
Likes Given: 583

Default

Quote:
Originally Posted by Zabuza View Post
Stir plate starters are left open to the air, with no airlock, that the agitated wort can pick up oxygen from the air. They also, however, pick up whatever else is in the air...that's why it's commonly recommended that you decant off the majority of the liquid and use (primarily) the slurry at bottom.

Thanks for the replies, you guys. I'm still worried that microorganism exposure with such a small amount of pitched yeast could be problematic, but I guess I'm overly concerned.
If you're not covering your starter container with a piece of foil or something, YDIW! I have never seen any container on a stir plate that's completely open.
__________________
Life begins at 60....1.060, that is!

www.dennybrew.com

http://www.experimentalbrew.com - the website for the book "Experimental Homebrewing"...coming Nov. 2014
Denny is offline
 
Reply With Quote
Old 10-09-2013, 11:41 PM   #7
ColoHox
Compulsive Hand Washer
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
ColoHox's Avatar
Recipes 
 
Join Date: Oct 2011
Location: Fort Collins, CO
Posts: 1,636
Liked 290 Times on 213 Posts
Likes Given: 390

Default

Quote:
Originally Posted by Zabuza View Post

Stir plate starters are left open to the air, with no airlock, that the agitated wort can pick up oxygen from the air. They also, however, pick up whatever else is in the air...that's why it's commonly recommended that you decant off the majority of the liquid and use (primarily) the slurry at bottom.

Thanks for the replies, you guys. I'm still worried that microorganism exposure with such a small amount of pitched yeast could be problematic, but I guess I'm overly concerned.
Your starters should always be covered, stir plate or not. And open starter is a recipe for an infected batch for sure. It is commonly recommended to crash and decant your starter so you don't pour weak, flavorless starter wort into your good beer, not to pour off other microbes.
__________________
Bacteria are the only culture some people have.
ColoHox is offline
 
Reply With Quote
Old 10-10-2013, 12:05 AM   #8
Zabuza
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2012
Posts: 172
Liked 4 Times on 4 Posts
Likes Given: 9

Default

Whoa, guys, I get it. Typically, though, people advocate not tightening the foil completely (otherwise it would just be pushed off by the pressure and no air could get in to oxygenate the wort). So, you either cover it loosely or poke holes in the top. I mean, there're even foam plugs for sale on various sites for starters to allow air exchange AND co2 blowoff. Either technique prevents there being a seal and exposes the starter to airborne microbes - there's no way around that. Typically, what causes us not to worry about it is the large amount of co2 being released, the relatively large pitching rates for starters (the yeast crowds out other organisms), and the short amount of time starters are active for.

All three of those things are absent in this scenario, and thus the cause for concern.

EDIT: I see that I wasn't clear when I said "open." All I meant is that a perfect seal is not used, and thus the starter is 'open' to the air (in a loose sense). I know some sort of cover is necessary, but the ones used do not achieve a true cover like an airlock - a one-way seal.
Zabuza is offline
 
Reply With Quote
Old 10-10-2013, 12:24 AM   #9
ColoHox
Compulsive Hand Washer
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
ColoHox's Avatar
Recipes 
 
Join Date: Oct 2011
Location: Fort Collins, CO
Posts: 1,636
Liked 290 Times on 213 Posts
Likes Given: 390

Default

Foam plug or foil lid, either works like a charm. Oxygen can eventually permeate a plastic carboy, so making it around some foil is no problem, no holes needed.

Most sources of contamination result from the handling, not the air, anyway. There is plenty of oxygen in the headspace, the stirring just promotes better gas exchange.

Stepping up bottle dregs is common and done successfully by many. Like Denny said, stirplate is fast, other than that it doesn't matter.
__________________
Bacteria are the only culture some people have.
ColoHox is offline
PastorofMuppets Likes This 
Reply With Quote
Old 10-10-2013, 02:53 AM   #10
Ichthy
Feedback Score: 0 reviews
Recipes 
 
Join Date: Sep 2009
Location: Jackson, TN
Posts: 494
Liked 1 Times on 1 Posts
Likes Given: 1

Default

Wort becomes infected by dust-borne bacteria, not from the "air". The reason plugs work is because they prevent dust from falling in your starter. Stop the dust, prevent infections. Look up Pasteur's sterilized broth experiment.


Ichthy is offline
 
Reply With Quote
Reply


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Zero Dollar stir plate - not counting stir bar mrmrsdsg Chillers and Stir Plates 2 04-11-2013 05:46 AM
Dramatically improve your Stir Starter stir plate wildwest450 Chillers and Stir Plates 27 03-24-2012 12:05 AM
first time stir plate user, how aggressive should i stir? wncbrewer Fermentation & Yeast 3 01-14-2012 02:35 AM
Stir plate effectiveness concern-maybe too small of a stir bar? crlova2 Fermentation & Yeast 20 03-15-2011 06:06 PM
DIY Stir Plate, Stir Bar attracted to mounts littlejon326 Chillers and Stir Plates 5 03-13-2011 02:12 PM


Forum Jump

Newest Threads

LATEST SPONSOR DEALS