Is this mold?

[Sessionz]

Hi everyone! I brewed this sour ale last February and pitched Sour Batch Kidz. It formed a nice bubbly pellicle for about 4 months. I added several bottle dregs about 4 months ago and purged the headspace with Co2 once done. Over the past 2 months this new white later formed. I’m not sure if this is a pellicle or something else. Does this still looks safe? I was just about to pitch some fruit before bottling, but didn’t want to waste it if this didn’t look safe.

 

[Funky Frank]

That’s a fine looking pellicle! Still take a little taste before fruiting just to see what it’s like.

 

[Dgallo]

Doesn’t look like mold at all. Looks like a pellicle. I would top that beer up. You have a lot of headspace for aging a wild and adding fruit. The co2 will help but that much headspace will certainly increase your risk for mold once the fruit is added

 

[McUbermensch]

Agree with the above that it is a pellicle.

 

[Sessionz]

Thank you all for the feedback! This was my first foray into mixed culture brewing. I will taste and fruit if all is good. Definitely top up the headspace too!

 

[Sessionz]

One more quick question: is it advisable to rack to a new carboy when making my fruit addition? I used a 6 gal for the entire fermentation, but only fermented 5 gal of wort. I do have separate equipment for my wild brewing. I could top up with some fresh wort, but I’d prefer to fruit and let it sit for a few weeks vs waiting more months for complete fermentation of new wort and fruit.

 

[McUbermensch]

I like to have a set for mixed fermentation and clean fermentation just to be safe. I would leave it where it is. Adding fruit to the carboy it's already in should cause creation of CO2 that would purge the headspace of oxygen.

 

[mashpaddled]

Pellicle, completely fine but if it grew seemingly overnight you should check that the airlock is staying full and the bung is well secured so you don't have an air leak somewhere around the opening.

 

[Dgallo]

One more quick question: is it advisable to rack to a new carboy when making my fruit addition? I used a 6 gal for the entire fermentation, but only fermented 5 gal of wort. I do have separate equipment for my wild brewing. I could top up with some fresh wort, but I’d prefer to fruit and let it sit for a few weeks vs waiting more months for complete fermentation of new wort and fruit.

I don’t see a reason to rack to a secondary. You will pick up more o2 then the yeast/microbes will use during fermentation of the fruit and will cause some amount of oxidation to occur.

I would advise on just adding it to your primary with a .25-.50 gallons of wort. The volume of the fruit and added wort will greatly reduce the headspace and will decrease your risk of mold growing (you may still want to punch down the fruit every few days to further prevent mold growth).