Wyest 1332 - krausen sludgy as doom metal

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Well-Known Member
May 5, 2014
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Vancouver Island
Hey everyone.
I noticed a funny issue with Wyeast 1332 that I have never seen before.
I typically use dry yeasts (S04 and US05 are my go-to yeasts for ales and Belle Saison for saisons).
I brewed up an APA and used a wyeast 1332 smack pack (no starter). I wanted to do a bit of an experiment because this particular smack pack claimed at least 100 billion cells if used within 6 months of the manufacture date. I used it within a month of the manufacture date.
My 5 gallon batch O.G was 1.046 so 100 billion should have been ok (brewer's friend called for 80 billion). I activated the smack back about 3 hours before pitching and that sucker was puffed out like a mofo by pitching time.
Anyhow, I pitched at 20 Deg C (68 F) and fermentation took off within 12 hours with a nice krausen - no worries there. My fermentor temperature at that time was 20.5 Deg C (69 F). I left it for about 10 more hours and noticed that the temperature in the fermenter rose up to 22 Deg C (72 F). That's a bit warm for my blood so I put the fermenter into a swamp cooler and dropped the temp down to around 18 Deg C (65 F) over night. Here is where it gets weird. When I checked the fermentor this morning it had gone nuts and foamed over the top of the airlock. When cleaning out the airlock there was this super thick sludge on top of the bung - like paste. I was a lovely cream colour though. The rest of the krausen looks normal. I am now day 2 of fermentation and it is still going strong.
I am not worried about anything, I am simply curious is to what that sludge is. Is it yeast that escaped? Is it evaporated krausen?
Did I cause this by dropping temperature too quickly? Any thoughts from you gurus would be much appreciated!