Mold in beer?

Matt55matt · Jun 26, 2019

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Popped the secondary to move to keg. Looks horrible! What do I do?!? Beer is about 5% abv

IslandLizard · Jun 26, 2019

Sorry about that! ^
The positive news is, I don't see any fuzzies, which is a telltale for molds. Looks like a regular pellicle due to infection by another microorganism. Should be safe to sample, and drink if it tastes good.
Have you smelled or tasted it? It's probably sour, sometimes that's not a bad thing.

2 things:

Secondaries are really not needed for most beers (only very few exceptions). Most of us don't use them (anymore). Kit instructions tend to be notoriously bad and outdated. Secondaries can, and will cause a) oxidation and b) infections. Best strategy: Leave beer in primary until ready to bottle/keg.
If and when deciding to using secondaries, they should have minimal headspace left to prevent oxidation (and infections). Therefore, buckets are totally unsuitable as secondaries. Also, all care should be taken to prevent oxidizing the beer at any point (e.g., racking).

For you next beer, look into 100% liquid pre-purging kegs and filling the keg through the liquid out post. The lid remains on. Your beer will be so much better.

Andrew Hodgson · Jun 26, 2019

If it's not fuzzy...
Taste it , taste it!

Matt55matt · Jun 26, 2019

It does not taste that much different off the tap at the bottom. Maybe a hint of sourness. I’m thinking about transferring to keg and seeing how it comes out. Think the CO2 will kill the bacteria?

Will I need to sanitize my bucket and equipment differently after this? How about the keg since it has CO2?

RPh_Guy · Jun 26, 2019

The film in your photo is called a "pellicle", which is caused by wild yeast and/or bacteria. Beer with a pellicle is generally safe to drink.
Mold is entirely different. It looks different and can produce toxins and allergens, making it unsafe to drink.

Beer contaminated with wild microbes won't necessarily sour or have any other off-flavors.

I agree 100% with @IslandLizard -- skip the secondary. It has no benefit and only causes problems.

Since it smells/tastes fine, it's safe to package. Go ahead and package as normal.

Thoroughly clean all your equipment, after every brew:
After use, soak with PBW or fragrance-free Oxiclean. Use a soft sponge to remove residue. Disassemble spigots and anything else you can and soak that too.
Before use, wet everything with a good no-rinse sanitizer.
Use clean technique when handing the wort and beer -- assume all surfaces not rigorously cleaned & sanitized smooth surfaces have wild microbes on them, because they do. Air has wild microbes floating around in it too; reduce open exposure as much as reasonably possible.

CO2 does not kill anything; the wild microbes will survive in the keg until you clean it.

Hope this makes sense. Good luck & welcome to HBT!