Beer Forum

Fermented for 14 days at 65 degrees, and then cold crashed at 48 degrees. At 48 degrees I am now hearing a lot of yeast activity. What gives I have never experienced this before, what is your experience and or thoughts?


Brewed a really light wheat beer:



Candy Ass Hefe'

Method: Extract
Style: American Wheat Beer
Boil Time: 30 min
Batch Size: 2.25 gallons (fermenter volume)
Boil Size: 1.25 gallons
Boil Gravity: 1.028 (recipe based estimate)
Efficiency: 35% (steeping grains only)
Source: Topkick Brewing





Original Gravity:
1.034

Final Gravity:
1.009

ABV (standard):
3.26%

IBU (tinseth):
25.17

SRM (morey):
2.92

Fermentables

Amount Fermentable PPG °L Bill %
1 lb Liquid Malt Extract - Wheat 35 3 50%
1 lb Dry Malt Extract - Wheat - (late addition) 42 3 50%
2 lb Total


Hops

Amount Variety Type AA Use Time IBU
1 oz Saaz Leaf/Whole 3.5 Boil 30 min 25.17





Hops Summary

Amount Variety Type AA
1 oz Saaz Leaf/Whole 3.5


Yeast


White Labs - American Hefeweizen Ale Yeast WLP320



Attenuation (avg):
72.5%
Flocculation:
Low

Optimum Temp:
65 - 69 °F
Starter:
No




Target Water Profile: Dupont

Ca+2 Mg+2 Na+ Cl- SO4-2 HCO3-
14 1 4 15 9 61

When you say you are "hearing" yeast activity, what exactly do you mean? Are you sure it is yeast activity and not just CO2 coming out of solution (maybe you moved it and kicked up some particles to for it to nucleate on, or maybe the yeast flocs are making nucleation sites)?

Also, was it at terminal gravity and stable before you cold crashed? As in, did you measure the gravity or did you do it by time?
If you were using time, then the yeast can still be working away even though it looks done (krausen dropped and some of the yeast dropped out).

You could be pulling a little bit of air in through the airlock as the volume inside shrinks during cooling. I get this all the time when I have a decent amount of headspace in my glass carboy. It doesn't seem to cause any problems or off flavors in my situation.

Microbru wrote:You could be pulling a little bit of air in through the airlock as the volume inside shrinks during cooling. I get this all the time when I have a decent amount of headspace in my glass carboy. It doesn't seem to cause any problems or off flavors in my situation.

OK, I use the Mr. Beer Little Brown Keg currently, so there isn't an airlock, however it is designed so that air could be suck back in.

The reason I stated that there may be yeast activity is because it sound that same as during the fermentation phase only the temp is much lower now, so I am inclined to believe that it may be the CO2 coming out, but not really sure.

Ok. I use those once in a while for open ferment sours. Are actually hearing a noise then?

Microbru wrote:Ok. I use those once in a while for open ferment sours. Are actually hearing a noise then?

Yes, I am hearing a noise, I guess I will let it ride and see how it tastes.

I can't imagine that at 14 days and that low of an original gravity and small batch size that your beer would still be fermenting after 14 days. It is done. Package it up!