Possible Un-invited Guests in Brown Ale

What went wrong? Was this supposed to happen? Should I throw it out? What do I do now?

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scorriga
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Possible Un-invited Guests in Brown Ale

Post by scorriga »

My friend and I have a batch of Brown Ale that's about 2 days away from the end of it's bottle conditioning. In about 8 or 10 of the bottles, I have noticed some little clumps of material that are stuck to the inside of the bottle neck in the headspace above the beer. I almost might think it was yeast but the yeast seems to generally fall straitght to the bottom rather than find itself on the sides.

We're extremely careful with sanitization so on the one hand it's hard for me to believe that we would have fallen victim to an unwelcomed beer infection. When there is an infection problem, is it quite obvious or could something this subtle also turn out to be unwelcomed visitors?

Also, my understanding is that in the event of an infection, one really doesn't have to worry about making oneself ill--just perhaps consuming some beer that smells and tastes less than desireable. Is that accurate? I'm inclined to drink it to see what we've got and play it by ear if it doesn't taste too bad. Hopefully the concern is all for nothing and it will turn out fine!

Thanks for the help...
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Mesa Maltworks
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Re: Possible Un-invited Guests in Brown Ale

Post by Mesa Maltworks »

"...I have noticed some little clumps of material that are stuck to the inside of the bottle neck in the headspace above the beer. I almost might think it was yeast but the yeast seems to generally fall straitght to the bottom rather than find itself on the sides."

If the beer was tilted at any time after sediment had formed during conditioning, it is possible that a yeast colony could grow in the headspace.

"We're extremely careful with sanitization so on the one hand it's hard for me to believe that we would have fallen victim to an unwelcomed beer infection."

Well, it is still possible that this is not yeast. There are bacterium that produce what is known as a pellicle. This is a sort of slimy, gelatinous "blob" of cells, usually of acetic acid producing bacteria. There are also wild yeast that do this such as Brettanomyces Bruxillensis which are seen in Lambic fermentations doing this. If the beer has any hints of vinegar or cidery flavors... acetic acid producing bacteria is the source. If it has a sour flavor and an increased viscous mouthfeel, sometimes even "milkish" flavor, lactic acid producing bacteria is the source.

A visual test you can do is to very slowly tilt an unopened bottle until it contacts one of the growths, hold it there for a minute and slowly tilt the bottle back up to vertical. Observe the liquid runniff down the side of the bottle while doing so. If you see any traces of oily looking residue coming off the growth... it is definitely bacteria.

"Also, my understanding is that in the event of an infection, one really doesn't have to worry about making oneself ill--just perhaps consuming some beer that smells and tastes less than desireable. Is that accurate?"

Yes, there are no known pathogens that can live in normally formulated beer that will make humans ill. This is due to pH and alcohol content. The only exception to this are some experimental or historical recreation beers (that should never be made due to the danger) that contain meat products such as colonial Cock Ale. There is evidence that the composition of such beers allow the possibility for very dangerous pathogens to grow. This occurs also when canning meat containing meals that were not exposed to enough heat or for long enough time to pasturize it.

Hope this helped!
Make your next beer (or spirit) a local one!!!!

Eric Watson
Head Distiller & Brewer

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Georgetown, Grand Cayman
Cayman Islands
scorriga
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Possible Un-invited Guests

Post by scorriga »

Thanks for the reply. I have since opened and drank several bottles from this batch (including those that had these little "clumps" in the headspace) and noticed no odd tastes or odors. The batch is really quite good. I suppose the most likely explanation is that relating to a small yeast colony having gotten started above the level of the liquid. Only about 1/4 of the bottles had this and, as I said, it doesn't seem to have affected the beer. Thanks again for the reply.
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