48F - too low for lager fermentation?

I brewed my first lager - munich helles - on Saturday (using wyeast munich lager 2308 with 1l starter on a stir plate). I pitched the yeast at about 68F, and transfered the fermentor to the basement, where I have about 48F. I saw no signs of fermentation yesterday (that's 48 hours after pitching).

I read all the posts saying that fermentation could start in 72 hours, but I'm still freaking out, that it won't start fermenting.

What do you think? How long should I wait?

Relax, have a beer...

I typically start lagers about 50-60, so 48 should be alright. There should still be plenty of active yeast, I would swirl it a little and wrap it in an old blanket for a day (or less). The fermentation will help warm it up and give it a kick start.

And if you're using an airlock, you might want to switch to a blow off tube with the blanket there.. You'd be suprised what could happen

All is good. I'd have expected some action by now, but you don't say how you know it's not fermenting. Are you judging by looking at the airlock? The first little bit might not show up, and if you are using a bucket, and don't have a perfect seal, the gas will escape around the lid, and not through the airlock.

48°F is fine for most (if not all) lager yeasts. In fact, it can produce a cleaner beer. The temps listed by the yeast companies are recommended temps, or optimal temps. Beer will ferment below those temps to a point, but fermentation may be a little slower.

Your yeast pitching rate may have been a bit light. I usually use a minimum of a 2 liter starter (on stir plate) per 5 gallons beer, and even that may be a little low for a lager. If it doesn't start within 3 days, then begin to worry and post back here.

@menschmaschine: you're right about pitching rate :-( I checked mlmalty pitching rate calculator when I was making ales, and I was sure that 1 liter on a stir plate will be enough for 5 gal lager batch. Obviously I was wrong...That's probably the cause of long lag

menschmaschine said:

If it doesn't start within 3 days, then begin to worry and post back here.

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within three days from now? or from pitching?

@Homercidal: I don't see any acitivity in the arlock and I don't see the bucket lid becoming convex, also I don't see any krausen.

I tried shaking the bucket a little, to move yeast to suspension, and there was some bubbles on the surface afterwards (so maybe there's sone c02 dissolved in the wort). I'll check on the krausen and airlock in a couple of hours anf report then.

yemu said:

within three days from now? or from pitching?

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Pitching... but it's not black and white. The longer the lag time the greater the risk for infection and the greater the production of off-flavors (e.g., diacetyl). So, it sounds like you'll need to do a good, timely, diacetyl rest.

yemu said:

I tried shaking the bucket a little, to move yeast to suspension, and there was some bubbles on the surface afterwards (so maybe there's sone c02 dissolved in the wort).

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That's a good sign.

Thanks,

I checked the bucket moment ago, and there was a kind of small krausen on the surface (like 3 areas about 2 inches in diameter).

The temp dropped to 47F.

Tommorow I'll check the gravity of the wort.

so far so not good :-(

still no airlock activity and no krausen after 96h

I took the sample in order to measure wort gravity, and it seems that it didn't drop more then 0.5 Plato (.002) which I think may be just my error of measurement.

I'm almost sure, there's problem with this batch, what do you think I should do?

96 hours is getting up there. I'd pitch more yeast if you can and leave it alone as much as you can. The more you open that thing, the more you risk infection.

and what do you think about warming it up to room temp, then pitching more yeast, and then when it starts fermenting, moving to the basement?

You could do that without too much ill-effect. However, keeping in mind that most lager yeast's optimal fermentation temperatures are 10-13°C, they're better off starting that way (or even slightly colder and warming up to optimal range)... despite what the yeast companies state. The reason is that the warmer they start, the more diacetyl they will produce... which can be eliminated with a good diacetyl rest, but I would also worry about other compounds being produced (e.g., esters) which can't be eliminated and would result in a not-so-clean lager.

So, with all of that in mind, one might consider making an exception to these concepts in your case because you're having trouble getting started and you just want to have some beer ferment. If your yeast haven't started yet (5 days?), it's likely that they won't ever start and were not very viable yeast in the first place. Perhaps they were old or exposed to extreme temperatures in shipping, etc. Even a 1 liter starter should start a 19 liter batch of lager in 5 days. So, ideally, you'd want to just pitch more yeast at this point. If this is not convenient or possible, then warming it up again to get things started is definitely a viable option just to save your beer.

Thanks again for your answer.

I think you're right that the yeast were not viable enough. These were the yeast frozen in glycerin by a friend of mine about a year ago. The starter I made was quite ok, but it was starting very slowly (i made 100ml and after two days I stepped it up to 1000ml), but finally there were a lot of yeast. It seems that they're were not healthy :-(

I'll pitch dry yeast today, and bring frementer home for a day to warm it up. Of course I'll do diacetyl rest later.

EDIT: I've just checked, and the fermentation started. i saw a bubble in the airlock and the bucket cover was convex, so theres co2. I also peeked under the cover and there was a lot more krausen than yesterday. So I think I'll just leave the thing as is for week, or week and a half. what do you think?

Temperature in my basement dropped to about 42F so I've decided to bring the fermentor upstairs. It's in a 59-60F now. Yestarday I checked how it's progressing and it went from 1.054 to 1.028 in over 3 weeks. I hope it'll get to 1.010-1.012 now. The important thing is it seems it's not contaminated, tastes pretty good, but of course too sweet. I must admit it smells strange, but I hope it will get better ;-)

Now to my question: After it's finished (around 1.012), should I take it back to the basement in the bucket and lager in 40-45F? Or should I bottle, leave it at 60F to carbonate and then lager in bottles? Either way: how long should I lager?

The strange odor will get better. It's probably sulfur compounds produced by lager yeasts that dissipate over time. For now, you could leave it at the warmer temp and I don't think it will negatively affect it. You're getting close to diacetyl rest gravity anyway and 60°F is a good temp for it. So, I'd let it finish primary upstairs.

1.010-12 is a significant amount to ask for a typical lager yeast to come from 1.054 (depending on fermentables). That's upwards of 80% attenuation. Don't be shocked if you don't get that low. Also, you may lose a point or two during lagering.

As for lagering, ideally you'd want to transfer it to a secondary fermenter and lager it at near 0°C. But 40°F isn't terrible. I prefer lagering not in bottles for two reasons: I think bulk lagering is beneficial for the beer because it has greater exposure to yeast (not necessarily quantitatively, but qualitatively) and your carbonation could end up different than you expect. If you lose, say, 2 points of gravity during lagering, that is CO2 produced that you may not have expected. Worst case scenario, you could end up with bottle bombs, albeit unlikely.

But, if you don't have a secondary fermenter available, then you could lager in the bottles. If you do, I'm not sure if you should carbonate first (room temp (if using dextrose/corn sugar) for ~3 weeks), then lager... or lager, then carbonate. Since the yeast are still "working" during lagering, I wonder if feeding them dextrose (easy to "digest") before lagering would make them not do as much as they normally would during lagering. The important thing is to get it out of primary when it's finished fermenting.

As for time, a 1.054 lager should probably lager between 5 and 8 weeks depending on how low your primary FG is (the lower, the shorter lagering time). In general, I would lager this one at least 6 weeks.

menschmaschine said:

1.010-12 is a significant amount to ask for a typical lager yeast to come from 1.054 (depending on fermentables). That's upwards of 80% attenuation. Don't be shocked if you don't get that low. Also, you may lose a point or two during lagering.

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I think you're right. Something like 1.016 is more realistic. I targeted 1.012 because it's the upper limit for the style, but I forgot that my starting gravity was higher then upper boundary for the Munich Helles (which is 1.051)

menschmaschine said:

As for lagering, ideally you'd want to transfer it to a secondary fermenter and lager it at near 0°C. But 40°F isn't terrible.

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I have glass carboy which i'm not using right now. But it's 6 gallons, and I'll have about 4.5 gallons of beer and I'm worried about oxygen that'll stay in the carboy.

Also I can't control temp in my basement. It's really cold now here in Warsaw, and I have 42F in the basement, but if it get warmer outside, it will also get warmer in the basement (50F is possible).

For now I plan to do as you say, that is transfer to the carboy when it's finished, and lager for a couple of weeks.

One more question, will I have to pitch fresh yeast after lagering?

PS. Thanks for all your answers menschmaschine!

yemu said:

One more question, will I have to pitch fresh yeast after lagering?

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My general rule is anything that lagers longer than 6 weeks gets fresh yeast (and I transfer from primary to secondary within a few days of primary fermentation completion). I've lagered a few batches for 6 weeks and they still carb fine, some batches slower than others. One thing I do is suck up a little bit of yeast sediment into the bottling bucket to make sure there's enough in there.

If you lager longer than 6 weeks, and you have the availability of dry lager yeast, you can add 1/4 to 1/2 pack to the bottling bucket.

thanks for the answers.

what do you think, how long will it take to finish from 1.028 to about 1.016 in 60F?

yemu said:

what do you think, how long will it take to finish from 1.028 to about 1.016 in 60F?

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It's difficult to say how long or what gravity it might reach without specifics of the recipe. My lagers finish in ~10 days, give or take. With a diacetyl rest and associated temperature changes, I usually get them to lagering at the 2 week mark.

With your increased lag time, low yeast pitch rate (did you ever pitch that dry yeast?), cold fermentation temps, etc., yours may take longer. It wouldn't be out of the realm of possibility to have it go 4 weeks (from start). You're just going to have to keep an eye on it's activity, krausen, etc... and when you really think it's done, take a gravity reading. If it's much higher than you expect, take another gravity reading a couple days later and see if it's come down any.

it's been for three weeks in a primary (cold: 42-49F), now it's for three days in warmer place, and gravity dropped to 1.016 from 1.028 since I've brought it from the basement. I hope it'll go lower ;-) to 1.012, because there's still a lot of krausen on the top.

I know this is a little late to help you now, but for your future reference, go to The Jamil Show page and download just about any lager show (munich helles, bock, american lager) and listen to it. Jamil waxes quite poetic about his lager brewing technique, and gives a ton of great information for lager brewers!

enderwig said:

I know this is a little late to help you now, but for your future reference, go to The Jamil Show page and download just about any lager show (munich helles, bock, american lager) and listen to it. Jamil waxes quite poetic about his lager brewing technique, and gives a ton of great information for lager brewers!

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thanks for the info, actually i've been listening to the show for a while, and i've listened to the munich helles episode before brewing it.
it seems it was not enough for me ;-)

Now that I look at my process during this batch, I'm pretty sure that the huge underpitching was the cause of my problems.

But the good point is, that the beer is ok, and I thing that after lagering it will be very tasty.

yemu said:

Thanks,

I checked the bucket moment ago, and there was a kind of small krausen on the surface (like 3 areas about 2 inches in diameter).

The temp dropped to 47F.

Tommorow I'll check the gravity of the wort.

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For future reference keep in mind that lager yeasts are bottom fermenting. They don't throw a big raft of krausen on top of the wort the way ale yeasts do. I agree with Mensch that you probably underpitched, and your yeast may have been stressed or less viable than a commercial yeast, but it looks like things are turning out okay. You brought the fermentation temperature up at just about the right time for a diacetyl rest. Looks like you are in good shape.

Let us know how it turns out.
Chad

I measured gravity today and it is now around 1.012, so I'm planning to put it to secondary, probably tommorow.
the beer tastes quite good, but the smells sulfury, which I think will disappear during lagering.

yemu said:

the beer tastes quite good, but the smells sulfury, which I think will disappear during lagering.

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That will most likely dissipate/dissappear.