Get your HBT Growlers, Shirts and Membership before the Rush!


Home Brew Forums > Home Brewing Beer > Lambic & Wild Brewing > Identifying wild yeast based on krausen/pellicle?
Reply
 
LinkBack Thread Tools
Old 04-04-2011, 05:47 PM   #1
winnph
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2010
Location: Takoma Park, MD
Posts: 144
Default Identifying wild yeast based on krausen/pellicle?

Until recently I'd never brewed with anything other than commercial Sacc strains, so I really have no idea what various yeast strains and bugs look like during various phases of fermentation. From what I gather, due to the blended nature of most lambic/sour brewing, it's difficult to determine which microbe is causing various qualities in the pellicle and whatnot. However, I figured it couldn't hurt to ask.

I posted a picture of this in the pellicle picture thread, but the point of that was to share, rather than seek input. I collected this yeast from dates, and I'm pretty sure it is a single species of yeast, since I streaked it on an agar plate and selected an isolated colony. However, I have no idea if it's Brett, Sacc, Zygosacc, etc., since I have no microscope or anything like that. I thought it might be Sacc at first, because it had a krausen that looked a lot like sacc, but now it's developing a pellicle (a little over a month in primary), so I'm wondering if maybe it's brett? The hydro sample I tasted about a week ago was definitely vaguely "earthy," but not overwhelmingly so, and not "funky" or "cherry pie" at all.

Here are pictures, first the krausen (a few days after pitching), then the pellicle forming (about a month after pitching):



__________________
My brewer's log and recipes
winnph is offline
 
Reply With Quote Quick reply to this message
Old 04-04-2011, 07:49 PM   #2
ReverseApacheMaster
Registered User
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2009
Location: Keller, Texas
Posts: 4,887
Liked 229 Times on 192 Posts

Default

In my (limited) experience with both sours and infections, it looks like at a minimum you have lactobacillus. Lacto tends to make those white specks, forms a bubbly pellicle and if given enough time may lay down a uniformly white layer across the surface.

__________________
ReverseApacheMaster is offline
 
Reply With Quote Quick reply to this message
Old 04-04-2011, 08:12 PM   #3
winnph
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2010
Location: Takoma Park, MD
Posts: 144
Default

Quote:
Originally Posted by ReverseApacheMaster View Post
In my (limited) experience with both sours and infections, it looks like at a minimum you have lactobacillus. Lacto tends to make those white specks, forms a bubbly pellicle and if given enough time may lay down a uniformly white layer across the surface.
That's interesting, since I really thought I was being careful with my sanitation and isolation process, and I even used sabouraud dextrose agar in an attempt to discourage bacterial growth. Obviously lacto infections can happen regardless of the source of the yeast, but it's kinda frustrating if that's the case here, since I was hoping to get a feel for this yeast's characteristics for use in future brews.

Question for microbiologist types: If I were to harvest a little of the pellicle and streak it on some regular agar plates, what would lactobacillus look like, as compared to yeast species? Does it have a recognizable growth pattern on agar?
__________________
My brewer's log and recipes
winnph is offline
 
Reply With Quote Quick reply to this message
Old 04-04-2011, 09:29 PM   #4
jvetter
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2007
Location: Maryland
Posts: 85
Default

This likes the pellicle on my lambics. I typically pitch sach, brett, lacto and pedio.

__________________

Keg1: Belgian IPA
Keg2: Wee Heavy
Keg3: Vienna Lager
Secondary: Rye Wine, Gluten Free Saison
Aging: Bourbon Barrel Imperial Stout w/ Brett, 2009 Lambic, Kriek, Framboise, 2010 Lambic, 2011 Lambic

jvetter is offline
 
Reply With Quote Quick reply to this message
Old 04-04-2011, 10:42 PM   #5
shanecb
Kvlt Brewer
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
shanecb's Avatar
Recipes 
 
Join Date: Mar 2010
Location: Pittsburgh, PA
Posts: 1,139
Liked 20 Times on 17 Posts
Likes Given: 9

Default

Even the same organism can form different looking pellicles each time, so it's hard to say.

__________________
A particular love for ancient, obsolete, or lesser-known style from both the US and abroad.

We are the Sons of Winter and Stars
We ́ve come from a far beyond time
Forever the fire burns in our hearts
Our world shall never die
- Wintersun
shanecb is offline
 
Reply With Quote Quick reply to this message
Old 04-04-2011, 11:30 PM   #6
ryane
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2008
Location: Washington
Posts: 805
Liked 5 Times on 5 Posts

Default

To me that doesnt really look strange, it looks like some bubbles and trub/protein on the top, especially if it doesnt taste sour I would say that its not infected

What was your recipe?

__________________
RyanBrews - check out all the bread/funk/pickling/cheese and other crazy things I try...
ryane is offline
 
Reply With Quote Quick reply to this message
Old 04-05-2011, 11:45 AM   #7
winnph
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2010
Location: Takoma Park, MD
Posts: 144
Default

Quote:
Originally Posted by ryane View Post
To me that doesnt really look strange, it looks like some bubbles and trub/protein on the top, especially if it doesnt taste sour I would say that its not infected

What was your recipe?
It was basically just DME (my first extract batch in years, been doing all-grain for awhile now), plus a little bit of hops, with the purpose of seeing what this wild yeast strain was like. As stated above, I had isolated the yeast from some dates by streaking it on agar, so I was hoping it was a single organism.

The beer had completely cleared and the surface was smooth, with just a few bits of trub/hop particles, and then about a week ago the white flecks started appearing and those bigger bubbles started forming, so it really does look more like a pellicle than just protein/trub, though I've never seen one form before.
__________________
My brewer's log and recipes
winnph is offline
 
Reply With Quote Quick reply to this message
Old 04-05-2011, 12:26 PM   #8
smokinghole
Senior Member
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
smokinghole's Avatar
Recipes 
 
Join Date: Nov 2009
Location: Lucid Dream Land
Posts: 2,916
Liked 122 Times on 101 Posts
Likes Given: 12

Default

Quote:
Originally Posted by winnph View Post
That's interesting, since I really thought I was being careful with my sanitation and isolation process, and I even used sabouraud dextrose agar in an attempt to discourage bacterial growth. Obviously lacto infections can happen regardless of the source of the yeast, but it's kinda frustrating if that's the case here, since I was hoping to get a feel for this yeast's characteristics for use in future brews.

Question for microbiologist types: If I were to harvest a little of the pellicle and streak it on some regular agar plates, what would lactobacillus look like, as compared to yeast species? Does it have a recognizable growth pattern on agar?
If you streak a plate and there's lactobacillus in the culture then the colonies will be very small. Lactobacillus is microaerobic and you actually need an anaerobic growth chamber to grow normal sized colonies for pure culturing techniques. Another way to rule out the lactobacillus is to use a pH differential media. If you streak the plate and the media is blue (as in wallerstein differential) and the plate turns green (due to acid production) with real small colonies, chances are it's lactobacillus.

Does the beer taste sour? If it doesn't I doubt you have a lactobacillus problem when you used pure culturing techniques to isolate a colony from the dates. You just have a strange looking pellicle is my guess.
__________________

Going through life is hard.
Going through life stupid is harder.

smokinghole is offline
 
Reply With Quote Quick reply to this message
Old 04-05-2011, 01:49 PM   #9
winnph
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2010
Location: Takoma Park, MD
Posts: 144
Default

Quote:
Originally Posted by smokinghole View Post
If you streak a plate and there's lactobacillus in the culture then the colonies will be very small. Lactobacillus is microaerobic and you actually need an anaerobic growth chamber to grow normal sized colonies for pure culturing techniques. Another way to rule out the lactobacillus is to use a pH differential media. If you streak the plate and the media is blue (as in wallerstein differential) and the plate turns green (due to acid production) with real small colonies, chances are it's lactobacillus.

Does the beer taste sour? If it doesn't I doubt you have a lactobacillus problem when you used pure culturing techniques to isolate a colony from the dates. You just have a strange looking pellicle is my guess.
Thanks for all that information! I don't have any pH differential media, so I'll just have to taste it when I pull my next hydrometer sample (planned for end of this week). The last sample, around March 21, was not sour, but the pellicle had not really taken shape yet. I'd noticed the white flecks forming on the surface when I pulled the sample, but it wasn't until about a week later that it really started creating the film and the bubbles started growing. I figured it must have been triggered by the introduction of oxygen when I removed the airlock for the first time since fermentation had begun, but I guess I could have introduced a bug of some sort.
__________________
My brewer's log and recipes
winnph is offline
 
Reply With Quote Quick reply to this message
Old 04-05-2011, 07:44 PM   #10
smokinghole
Senior Member
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
smokinghole's Avatar
Recipes 
 
Join Date: Nov 2009
Location: Lucid Dream Land
Posts: 2,916
Liked 122 Times on 101 Posts
Likes Given: 12

Default

Do you have any kind of pH indicator solution? If you do you can check the beer at different stages to see if it changes pH over time. That will also give an indication of either lactobacillus or pediococcus. Other thing to note. Though it's small and strain dependent brettanomyces can also produce acetic acid like pediococcus just that brett does it in much smaller quantities.

__________________

Going through life is hard.
Going through life stupid is harder.

smokinghole is offline
 
Reply With Quote Quick reply to this message
Reply



Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wild yeast from "wild" grapes DrJerryrigger Lambic & Wild Brewing 11 10-15-2011 01:52 AM
Possible pellicle forming on partially-wild brew? winnph Lambic & Wild Brewing 2 02-26-2011 07:13 PM
wild yeast zackmon21 Lambic & Wild Brewing 2 06-14-2010 12:36 AM
Is this wild yeast? realestatecat Lambic & Wild Brewing 3 01-14-2010 03:38 AM
Yeast Bank- Wild Yeast/bacteria Jsta Porter Lambic & Wild Brewing 7 04-21-2009 02:20 PM



Newest Threads

New

LATEST SPONSOR DEALS