Beer Forum

So yesterday I brewed my first lager (Marzen/Oktoberfest, OG 1.053) and put it in my converted chest freezer for fermentation. I'm using a Ranco single-stage digital controller and a thermowell; I'm fermenting in a plastic bucket using WLP830. In typical style, I made very sure of everything I had heard on the matter, and once things were already committed I read up to find I had likely mis-remembered...

So here's what happened: I cooled the wort using my immersion chiller, and it felt like about 72F. I've not yet been able to install a thermometer in my kettle, but ambient was about 79 and this was clearly colder. I had a 2L starter going on the stir plate for about 60 hours; I took it off in the morning to allow things to settle a bit so I could pour off the less-populated liquid, which I did. I oxygenated using O2 and a diffusion stone for 30 seconds, and pitched a little less than 1.5L in total. I was able to get the bucket into the freezer, inserted the probe into the thermowell, and off we went.

I thought I had remembered hearing about cooling down about 1 degree an hour to fermentation temp, which I intended to be 52F. However, the probe thought that my wort was 78F, which was WAY too high. This was at 2:pm. The freezer was set at 66 at first. By 5:pm it was down to 72F, and 9:pm saw it down to 67F. At that point I was bringing it down about a degree an hour, minus some sleep. When I left this morning for work we were, I think, in the high 50s (57-78).

I had considered trying to chill down to fermentation temp before pitching, but was concerned that my nice, clean wort would just be sitting there and any small thing that was in there could grow. I'm now questioning the wisdom of that decision.

I'm also noting that while I've got this set for a 1 degree swing, the setup has enough inertia that I'll see a beer temp of 1-3 degrees lower than the setting by the time the the downward swing stops.

So here are my observations/questions:
1) I am assuming that next time I shouldn't worry so much about infection and crash chill the wort overnight, oxygenating and pitching in the morning. Is this correct?
2) Just how much did I screw up ester-wise by this fermentation schedule? I was getting airlock activity 3 hours after pitching, and it was quite active after 7 hours. It was still active this morning, so it may be that the yeast is hardy enough.
3) Is the 1-3 degree under-temp swing a problem? Should I set the controller a degree or two higher than desired to take this into account?
4) So in the low 50s how long does fermentation typically take? I know the yeast has its own schedule, but I'd like to keep the bucket closed as long as possible before starting to take gravity readings.

dlevey wrote:So here are my observations/questions:
1) I am assuming that next time I shouldn't worry so much about infection and crash chill the wort overnight, oxygenating and pitching in the morning. Is this correct?
2) Just how much did I screw up ester-wise by this fermentation schedule? I was getting airlock activity 3 hours after pitching, and it was quite active after 7 hours. It was still active this morning, so it may be that the yeast is hardy enough.
3) Is the 1-3 degree under-temp swing a problem? Should I set the controller a degree or two higher than desired to take this into account?
4) So in the low 50s how long does fermentation typically take? I know the yeast has its own schedule, but I'd like to keep the bucket closed as long as possible before starting to take gravity readings.

1) Yes, that's SOP for me in the Summer and it works fine. The wort typically goes into the fridge at 70F and the next morning it is at 45F. Cheaper than 20 lbs of ice. You don't want it to go longer than overnight though.
2) Plise won a medal at the NHC second round with a Munich Helles when he used to do his lager fermentations this way. Although he didn't mention that beer specifically, this was before he 'saw the light' and was still pitching warm. You'll know when you taste the finished beer, it's more likely to have increased esters WRT a cold pitched beer, but that doesn't mean it will be bad.
3) You can try to guess at how much carryover cooling you'll have once the compressor shuts off, but I wouldn't worry about it. 50, 49, 48, close enough.
4) IME a cold-pitched healthy lager yeast will get to TG in 7-10 days at 50F on a 1.050-1.060 beer. It could be faster but I haven't checked it earlier than 7 days. It all depends on the yeast health though, so as you said go by the yeast's schedule.

Thank you very much for the response. I had completely forgotten about the Jon/Jamil showdown on pitching temps, and this helps me relax a bit about my final product. For next time, I will chill first and then pitch (which will allow me to chill the starter too and pour off more inactive liquid).

Now that things seem to be stable, I've not yet caught the beer at less than 1 degree below set temp, which makes sense. As of this morning, about 41 hours after pitching (and at 51F) I am still seeing airlock activity so it seems that the rapid cooling didn't harm things too much. As for timing, I'll start checking perhaps mid-week next week, or on the weekend, to see if it's time to lager. Since I am using the same chest freezer as a kegerator, that'll help get those summer beers closer to serving temps, so I'm looking forward to that.

Thanks again!

Get a digital thermometer to take the temp of your wort while cooling. Don't use your hand! All you are comparing it to is your body temp.

I don't see why you would want to slowly chill down to ferm temp. You want to do it as quickly as possible so you can get the yeast in before anything else takes over. Set your chest to ferm temp, put the bucket in and let it get down as quickly as it can. Pitch when ready.

I brewed once this summer when it was 1183* Kevlar outside, and even hotter in my garage where I was brewing. By the time I'd reached about 80* F on the wort, I started to transfer and get the carboy into the ferm chamber which was set @ 45* F to get the last 12*F I wanted out of the beer to 68* F. Once it reached fermentation temp, I pitched the yeast, packed the car and drove to Arkansas for a weekend of fishing with the in laws.

Would anyone like to guess what I forgot to do before I left that meant I came home 4 days later to a still beer and no movement in gravity at all?

You forgot to set chamber back to fermentation temp?

or less likely You forgot to oxygenate?

lucybear999 wrote:You forgot to set chamber back to fermentation temp?

or less likely You forgot to oxygenate?

1056 does not work @ 45*F. If anyone wanted to experiment with this yeast at that temperature, don't bother, I've concluded that it doesn't work.

Moral of the story - if you are using your chamber to finish off that last 10 degrees, don't forget to set it back. That beer is kind of drinkable, but there's a definite yeast derived off flavor in there.