Massive krausen

[sinned34]

I'm wondering if temperature regulation can cause a huge amount of krausen.

On this past Sunday I brewed up 46L (10 gallons) of Maibock. I split the batch in half and put each half into a 40L (10g) primary bucket. I aerated both for about five minutes each with a paint mixer and then rehydrated two packets of Danstar Nottingham dry yeast, pitching one packet into each bucket.

I then left one bucket in my basement storage area that averages between 65-75 degrees F. The other bucket I put into a small freezer that I just purchased a temperature controller for and set it to 65 degrees F (the freezer isn't big enough for two primaries at the same time).

By Monday afternoon, the bucket outside the freezer had a krausen form and climb up the bucket about 4-5 inches before falling. The bucket in the freezer didn't begin forming a krausen until Tuesday morning. Tuesday evening I went to take a look at the batch in the freezer, and the krausen actually filled up the 10g bucket and spilled over a small amount.

I've never seen a krausen on 23L (5g) of wort fill up and spill out of a 10g bucket. Is it the regulated temperature that caused the krausen to form so huge in the freezer compared to the bucket outside of it? Or could it be do to pressure building up in the sealed freezer that caused the krausen to expand so much?

Anybody have any ideas about what could cause such a difference in krausen formation?

 

[mrlousi7]

If you are using priming sugar for some reason then there could be less CO2 in solution and you may need to up it a bit (assuming your ferm temps were lower than 76), but it was such a small swing I would pretend it didn't even happen.

 

[Weezy]

Deleted. Misread your post.

 

[porterpounder]

The batch may have stratified before splitting, leaving a higher concentration of sugar in the freezer batch. With a healthy pitch and and active fermentation the higher concentration may have allowed a more vigorous fermentation and subsequent excessive krausen. Otherwise I'd assume the warmer batch would usually be the one to foam more. Weird.

 

[kombat]

+1 to PorterPounder, apparently the only one who actually read the OP's post.

 

[alane1]

The only other thing that I can think of is trub concentration. Was the freezer batch the one from the bottom half of the BK? From what I understand trub is rich in lipids that the yeast break down into nutrients.

 

[sinned34]

Mrlousi7: I'm afraid there was no sugar in the beer. Just pilsner, vienna, and munich 10L malt.

Porterpounder and Alane1: I used a siphon to drain from the bottom of the kettle into the first bucket which went into the freezer, then I filled the second bucket that stayed outside. I measured the OG of both batches, and they both came in at 1.072. But perhaps the first fermenter was filled with more fermentable wort? I guess I'll find out when I measure the FG.

Thanks for the input, everyone. Maybe this is just one of those one-off weird things that happens. I'll have to see if the same thing happens when I brew up a double IPA in March.