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Signs of infection?

So about 2 months ago, I made a Brickwarmer red ale. Fermtation time is only a month but things have gotten busy with my wife and I have a new baby so it’s been sitting. I check it ever couple of days. Temp is also in between 68 and 70 in the swamp cooler. It’s in secondary now. I really don’t see any signs of infection but what should I be looking for?

You might see something like this:

Or like this:

Other than quite a bit of headspace, that looks like it might be ok. Usually visual signs of an infection are pretty obvious. Of course, not all infections get pellicles, so a gravity measurement much lower than expected, or an off flavor or aroma can be a better indicator. Keep an eye on it, though - the small bubbles at the surface might just be CO2 off-gassing, but if you start seeing filmy, persistent bubbles then you might want to be concerned.

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The most common sign of infection starts as a blueish white oil slick across the surface of the beer. This can turn into a mass of spider webs and large bubbles. Infectious bacteria will are aerobic. An infection will always appear on the surface of the beer.

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The little things on top look like sediment. I know that do ant make sense it is on the top of the beer. That is my 6 gallon glass carboy that I use for secondary. Should I switch to a 5 gallon glass carboy for secondary? I use a 7 gallon fermonster for primary. My last beer, bourbon barrel porter which turned out sooo good, looked like that last time.

Btw, this circled part is actually on the top of beer. I know it’s hard to tell if it’s on the beer or on the glass.

In the presence of oxygen, many spoilage microbes will produce a pellicle on the surface of the beer. But not all of them. Lacto plantarum often will not produce a pellicle, even when there’s lots of oxygen available. And if the headspace is purged with CO2, an active infection generally won’t produce a pellicle. So a lack of pellicle is not a good indication for lack of infection.

Also, there are plenty of spoilage microbes that are obligate anaerobes, and will die in the presence of oxygen. Clostridium and megasphaera, for example. Others, like brett, pedio, and lacto are facultative anaerobes, and while they enjoy a high oxygen environment, they do just fine anaerobically.

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I wouldn’t transfer this one, but it’s a good idea in the future to use a 5-gallon secondary to minimize your headspace. Unless you’re going to dry hop after some time in secondary, which will turn into a volcano if you don’t have enough room at top. Guess how I discovered this…

Chances are that you have some CO2 coming out of suspension, which can lift the sediment to the surface of the beer. This will happen if it warms up, or if a storm comes through and the air pressure drops. Lots of things can cause it. But keep an eye on it for another week or so - there’s a spot just left of center that looks like a bubble forming. If this starts growing, then there might be reason for concern.

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Much more complete information. Came back in to edit my post after some thought.

Would add…otherwise taste and aroma will indicate whether there is infection…

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Cheers… hope I didn’t come across as jumping on you. Pellicle is a clear sign of infection, but without the pellicle you can rely on taste, smell, and hydrometer readings to determine if there’s an infected batch. A batch can certainly be infected without showing a pellicle…

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I always give my beer a little taste when transferring to see if it taste okay. Crazy how much the taste changed before bottling and after it is carbonated.

I hope to bottle in a week. Things have just gotten a little crazy with the new baby and work. I need some more caps so I will put up a 5 gallon carboy at my LBHS for when I do a standard secondary. Should I purge with CO2 on a 5 gallon carboy?

No, purging is not necessary with the small headspace in a 5-gallon carboy. Coming out of primary it’ll be full of CO2, and the agitation from racking it will knock a good amount of CO2 out of suspension. It purges itself. You’re mostly ok with a large headspace, too, but the larger volume of air makes it more susceptible to temperature and pressure changes creating a bit of a vacuum, which will pull in oxygen through the airlock.

If you’re bottling it in a week, just leave it where it is. You’ll do more harm by transferring it more than necessary. If you were leaving it there for 6 months, then you might want to get it in a smaller container.

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Yikes! This makes me want to go and resanitize my conicals! And you posted those pics on Friday the 13th… you dirty dog! Now I feel like my screen is infected.

@porkchop gives great advice on this. If it starts turning hairy and/or spider webs then worry. I’m glad your switching to a 5gal carboy to limit your head space. This will relieve you of some stress in the future.

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Don’t fear the funk, bro! That first beer turned out incredible, like hoppy, musty pineapple juice. The second one is cantillon dregs going to work on a semi-turbid mash. Can’t wait to try that one! In two more years… :disappointed:

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