I have a pellicle but my beer is not sour

[jman300sd]

Opened the bucket on my pale ale a week ago and found a nice pellicle covering the entire surface. Been on Primary for about 2 months (kinda forgot about it), but I pulled a sample and it tastes clean. Gravity was at 1.010 so I just stuck to the original plan and it racked it onto some Oak cubes. I tried my best to leave the pellicle layer behind when I was racking. Checked it in secondary today and the pellicle has completely regrown - but it still tastes clean. So I have two questions:
1. If its clean right now should I still assume that if I leave it to age it will become sour?
2. If I want to avoid it becoming sour and I bottle it now will I have bottle bombs with a gravity of 1.010?

 

[Coff]

Its pretty much impossible for anyone to know what you have growing in your beer without tasting it or looking at it under a scope. Your answer to question #1 is, who knows, its probably wild yeast and it may not necessarily contain a souring organism.

If you have the luxury, let it age out for a few months and see how it progresses. Take a gravity sample and if it is stable then you know youre probably fine, if it moves then continue to age it until the gravity is stable.

You could bottle the beer, let it carb up then store the all cold and drink them young. But really, none of us know what has infected your beer so its kind of a guess on whether or not you'll have bombs.

 

[jman300sd]

So ----- I left this on oak cubes for the past 8 weeks. The pellicle growth is quite intense. But the flavor is superb! Gravity has dropped from 1.010 to 1.006 and the wood flavor is quite perfect. Not sour at all! If I had to guess I would think this is just the result of some wild yeast that got in there, but who knows. I'm going to bottle it next week with a lower carbonation (maybe 1.75 volumes) as I assume whatever is there will keep munching away and will carbonate it a little more. I'm excited!

Question - I want to harvest some of this pellicle and save it for a batch down the road to see if I can recreate the same results. If I skoop some of this stuff out, can I add it to some pre boiled water in a sanitized jar and keep it the fridge for a month or two?

 

[smokinghole]

Just keep some of the beer in a vial and that should provide the yeast. You could even boil up some extract to grow it up to more of a slurry.

The pellicle, or skin, is a polysaccharide complex formed by the yeasts or bacteria that grows on the surface of beer. In my experience they only form and get thick/white in fermentors that have more oxygen permeation. I've done beers in stainless, glass, and better bottles. They never got a thick pellicle really, then I did a few in a speidel fermentor and my pellicles have been crazy looking.

 

[ryanhope]

The pellicle, or skin, is a polysaccharide complex formed by the yeasts or bacteria that grows on the surface of beer. In my experience they only form and get thick/white in fermentors that have more oxygen permeation. I've done beers in stainless, glass, and better bottles. They never got a thick pellicle really, then I did a few in a speidel fermentor and my pellicles have been crazy looking.

Just to add a little more clarification to this. The pellicle is produced by brett, not bacteria like lacto and pedio, which don't produce pellicles. Lacto and pedio are the real source produces so you shouldn't equate a pellicle with sour.

 

[chad_]

Lacto and pedio (bacteria) don't produce pellicles and are the real source produces (not brett). You shouldn't equate a pellicle with sour.

I think you meant that lacto and pedio are the real *sour *producers

 

[ryanhope]

I think you meant that lacto and pedio are the real *sour *producers

That is what I meant (and said) but I can see how it does not come off that clear Edited the post for clarity.

 

[jman300sd]

odd....I have brewed brett beers with no pellicle formation. I guess just less oxygen?

 

[smokinghole]

I am fairly certain bacteria in a blend would give a pellicle as well, not just Brett. I will hopefully have some ECY23 to use soon. That is just a blend of lactobacillus and a Belgian saccharomyces. So if it give off a pellicle the claim of brett only forming a pellicle is bunk. I brewed a dubbel two different times with only saccharomyces and bacteria. one time I left it ferment and never opened the keg to check on it until bottling there was no pellicle. The second time I did the beer I got a pellicle but I also opened it for a gravity check at one point.

 

[ryanhope]

I am fairly certain bacteria in a blend would give a pellicle as well, not just Brett.

Pellicles are a yeast thing so I suppose a saccharomyces based yeast could also produce one its just way more common with brett. I am 99% certain lacto and pedio do not form pellicles.

 

[Coff]

Question - I want to harvest some of this pellicle and save it for a batch down the road to see if I can recreate the same results. If I skoop some of this stuff out, can I add it to some pre boiled water in a sanitized jar and keep it the fridge for a month or two?

Or event harvest those Oak cubes and store them in a vial with some fresh wort, that should save your bugs pretty well. Then the next batch you can just add the oak cubes and you should be good to go.

 

[sweetcell]

I am 99% certain lacto and pedio do not form pellicles.

lacto can make a pellicle.

https://www.homebrewtalk.com/f127/pellicle-photo-collection-174033/index105.html#post5261665 - lacto-only starter

https://www.homebrewtalk.com/f127/pellicle-photo-collection-174033/index111.html#post5346533 (EC06 contains sacc and lacto d.)

https://www.homebrewtalk.com/f127/pellicle-photo-collection-174033/index111.html#post5346677 (sour mash = lacto only)

pedio is always pitched with brett (to deal with the diacetyl it produces), so no way of knowing if it would create a pellicle on its own.

 

[ryanhope]

lacto can make a pellicle.

https://www.homebrewtalk.com/f127/pellicle-photo-collection-174033/index105.html#post5261665 - lacto-only starter

https://www.homebrewtalk.com/f127/pellicle-photo-collection-174033/index111.html#post5346533 (EC06 contains sacc and lacto d.)

https://www.homebrewtalk.com/f127/pellicle-photo-collection-174033/index111.html#post5346677 (sour mash = lacto only)

pedio is always pitched with brett (to deal with the diacetyl it produces), so no way of knowing if it would create a pellicle on its own.

The first and third links are most likely contaminated with wild yeast. I've never read anything that has ever said pure lacto or pedio can produce pellicles. Im going to stand by my statement that pellicles are a yeast thing not a bacteria thing.

 

[sweetcell]

The first and third links are most likely contaminated with wild yeast. I've never read anything that has ever said pure lacto or pedio can produce pellicles. Im going to stand by my statement that pellicles are a yeast thing not a bacteria thing.

saying that 1 & 3 are wild yeast is grasping, IMO. so all berlinerwiesses are contaminated with wild yeast? maybe, but the much simpler & more likely explanation is that it's lacto. i'd dig up more pictures & links for you but i doubt they would change your mind so i won't bother

however, if you have references that state that lacto never throws a pellicle on its own i'd love to see them. there is always something to learn about bugs.

 

[loftybrewer]

So in my experience one thing about lacto pellicles as opposed to brett pellicles is that lacto pellicles sort of creep up the side of your carboy as if they are coming to get you...while you sleep. It looks like an EKG or something. My brett pellicles have only ever reached the meniscus. I have also gotten a sort of oil slick looking thing from just sacc, but no pellicle. I can't find it right now, but there was a thread a while back about a white labs strain that some people had a pellicle-ish thing appear over.

 

[ryanhope]

I just skimmed though F.G. Priest's Brewing Microbiology. Here are the things that form pellicles: acetobacter,

Acetic acid bacteria (ex. acetobacter) - these form the greasy looking pellicles

Dekkera/Brettanomyces - no description in book

Debaryomyces/Pichia/Issatchenkia and Candida - these form the flaky looking pellicles

So, I was partly wrong in saying that bacteria don't produce pellicles. Im still looking for something more scientific pictures that prove lacto or pedio produce pellicles.

 

[TimT]

So, I was partly wrong in saying that bacteria don't produce pellicles. Im still looking for something more scientific pictures that prove lacto or pedio produce pellicles.

Terms you may want to look are "biofilm" and "SCOBY" Kombucha and ginger beer plant are the prime examples of yeast and bacteria making a pellicle. There are lots of organisms that make crud on top together or on their own. I don't believe pedio is known to make a pellicle but some/all lactobacillus strains will. Pedio is not happy with O2 so it makes sense that it would not thrive on the surface.