Is my beer infected?

[andrewjones]

Hi,

I've brewed a German-style Wheat Beer, standard recipe. However, when bottling I noticed this foam on the top, which I don't think I've noticed before (but only a few brews in to my homebrew career).

I'm not sure what this foam is, could it be an infection?

I continued to bottle and 4 days later in I've noticed some, but not all of the bottles have this foam/sediment on top, which again I haven't noticed before.

I know the order of my bottles and these were towards the end of the batch. I opened one and sure enough it gushed everywhere (obviously in hindsight, but wish I had done it over the sink...).

Bottles earlier in the batch look ok, presumably not yet carbonated as I can still squeeze. But the later bottles look like this and can't be squeezed.

I tasted it and it's ok I think, though maybe not as I was expecting, but it's my first wheat so not sure. Doesn't look all that appetising though!

For priming I added 268g of cane sugar, boiled in 370ml water and stirred in once cooled to 20c. Have been stored at 20c since.

Is this infected, or something else? Will some of the batch be fine if they look ok now?

 

[gnef]

As a general rule, everything is infected to some degree - it is impossible for us to be 100% sterile in the brewing process. Now, some infections are worse than others, and the growth of an infection depends on many variables.

Now, specifically for yours, yes, that description fits a classic infection. It should not be harmful to you, and you may not notice any significant off flavors for a while. I would recommend you keep the bottles chilled, and drink them fairly quickly if possible.

Since it looks like you are using plastic bottles, you don't need to worry as much about bottle bombs, but still be careful. You may also want to dispose of the plastic bottles after this batch so that you don't contaminate subsequent batches.

It may be possible that the priming sugar wasn't evenly distributed, but I would personally treat this batch as significantly infected, and move forward with that in mind, and do a thorough cleaning of your cold-side equipment - anything that touches the wort/beer during or after chilling.

 

[Gnomebrewer]

It's hard to tell from the photo, but doesn't look like a pellicle (from infection/contamination) to me. The foaming in the bottle is quite normal if there's rapid activity. If it is 'infected', all bottles will be affected, not just the ones bottled towards the end.

268g of sugar in a 5gal batch gives somewhere around 4.4 volumes of CO2, which is a lot (even for a wheat beer). If it wasn't mixed properly, some bottles will be higher than that again. That's what I suspect the issue is - later bottles getting most of the sugar. Time will tell.

 

[VikeMan]

For priming I added 268g of cane sugar, boiled in 370ml water and stirred in once cooled to 20c. Have been stored at 20c since.

If you really used that much sugar, and if this was a 5 gallon batch, your bottles may be at risk of exploding, especially if some got more of that sugar than others.

You might consider opening (to let some pressure out) and recapping, and/or keeping these bottles very cold.

 

[Gnomebrewer]

If you really used that much sugar, and if this was a 5 gallon batch, your bottles may be at risk of exploding, especially if some got more of that sugar than others.

It sounds like they're all in plastic bottles - they shouldn't explode. Also, it makes it easier to vent some pressure.

 

[gnef]

oh man, it has been so long since I've bottled, that I didn't even pay attention to the mass of sugar added! (I would actually still treat it as infected in terms of bottle pressure and drinking quickly though, be careful!)

 

[Calder]

It doesn't look like an infection, no indication of a pellicle. An infection would take a long time to convert any long chain sugars in an alcoholic environment, so it is not an infection which is causing the high carbonation.

268 grams is 9.5 ozs of sugar. That is a lot. I would use about half that for a 5 gallon (US gallon) batch. What size was your batch.

I suspect you just used too much sugar. Why some seem more carbonated than others; I suspect the sugar wasn't mixed too well, but I usually find priming sugar mixes well.

 

[andrewjones]

Thanks everyone for your replies, really appreciate it!

I had around 22 litres when I started fermenting. I used the priming calculator at Beer Priming Calculator - Brewer's Friend and was hoping for about 3.9, which seemed to be the average for a wheat beer.

As some bottles seem over carbonated and some under, sounds like mixing is the likely issue. Guess I need to work on my priming and mixing technique

Thanks again!

 

[Gnomebrewer]

3.9 is good (I target 3.8 with wheat beers).
The 'Amount Being Packaged' should be less than the volume when it starts fermenting (unless you mix sugar straight in to the fermenter). How did you mix the priming sugar? Bottling bucket, fermenter or direct into bottles?

 

[andrewjones]

I mixed it straight in to the fermenter, and bottled using the tap attached (with a bottle filler).

I did stir, though not too much because I didn't want to disrupt the sediment.

 

[Gnomebrewer]

Next time, if you don't have a bottling bucket, try dosing each bottle directly with sugar solution using a large syringe. It's quite fast, accurate and easy once you get used to it.

 

[andrewjones]

Thanks Gnomebrewer, will look in to that for next time!