First Time Lagering Questions

Well I've nearly completed my lagering setup (free fridge is running and thermostat is on order) so am getting my ducks in a row on brewing a lager. Looked through the forums and skimmed 'how to brew' and seems there's not any one correct answer on some of these things, so thought I'd throw some questions out...

Yeast - Palmer seems to advocate a big starter or alternatively pitch at warmer temps then gradually reduce to lager fermenting temps. In the forum I've also seen posts that say to pitch a double batch (if using dry yeast) in lieu of a starter. I'm a fan of dry yeast, so would pitching 2 packs at the optimum fermenting temp be recommended?

If so, is the best technique to rack the wort to carboy, seal up without pitching and refrigerate to get down to optimum temp before pitching?

Diacetyl Rest - this appears to be done at some nebulous time near the end of fermentation, but it's not 100% clear to me when. Palmer suggests using a glass carboy and d-rest when you see the activity (churning) slow. I do use glass carboy, so is this a good method?

For the d-rest, do I just turn my fridge thermostat up to the right temp (60 - 65??)? Or do I step it up slowly (and if so how slowly)?

Also, how long is d-rest? Two days or so?

Lagering - looks like lagering is done at temps about 10 degrees less than fermentation. Do I lager immediately after d-rest or do I go back to regular fermenting temps first? In either case, is the temperature reduction immediate or gradual?

Thanks for any feedback

I've never used dry lager yeast, so I can't answer that question. I believe that Menschmachine has posted that he was very pleased with dry lager yeast, so maybe see what he has to say on that.

Lagers really aren't any more difficult than ales, now that you have temperature control.

I chill my wort to 50 degrees, using the wort chiller and/or ice bath. You want to pitch the yeast sooner, rather than later, so chilling it to the right temp is a good way to start. I take my yeast starter out of the fridge, decant the spent wort, and let it warm up to 46-48 degrees while I brew. Then, I add that yeast slurry to my 50 degree wort. The slightly lower temperature yeast seem to love the slightly warmer wort. I then keep it at 50 degrees until the fermentation is about 75% finished.

At that point is when the diacetyl rest is done, if you're doing one. I've found that some yeast strains don't produce much diacetyl and if you pitch at appropriate temps, sometimes they aren't needed. It won't hurt the beer to do one, though, just as a matter of course. So, your beer is 75% finished. That's the time to raise the temperature 10 degrees, and allow the beer to sit at that temp for 24-48 hours. I'm talking beer temperature here, not ambient air temperature. If you raise the temperature of the freezer, keep an eye on the temperature of the beer and give it time once it reaches the diacetyl rest temp. You can also taste the beer when you take the SG samples- if it's a butter bomb, or you have "slickness" on the tongue, you can make the diacetyl rest longer than 24-48 hours, until the diacetyl is cleaned up.

After the diacetyl rest, fermentation will be completely finished, but check the SG to make sure. Then, rack and begin lagering. I like to lower the temp 5 degrees per day until I am at 34 degrees and that starts the lagering period.

I've been trying to lager one week for each 10 points of starting gravity. So, for an 1.080 lager, I've lagered 8 weeks or so.

If you're bottling, some people like to add a bit of fresh yeast at that time to ensure there are enough yeast for carbonation. I've done it both ways, and had good results each time but I'd hate to not have one carb up after all that work, so I tend to re-yeast a little at bottling time. I boil and cool the priming solution and then add 1/4 package dry yeast to that, stir well, and then rack the beer into it.

Thanks Yooper (I've always wanted to say that!)...I assume you use SG to determine the 75% point for fermentation, but what's the indicator that you're close to that point short of constantly checking SG?

I've had dry lager yeasts that stalled or were very sluggish getting going. One option is to pitch warm, say 70 deg, and then slowly cool to 50 for fermentation. A D-rest is a must if you go this approach however as it will definitely be needed to clean up the mess the yeast made from the warm start.

BruDaddy said:

Thanks Yooper (I've always wanted to say that!)...I assume you use SG to determine the 75% point for fermentation, but what's the indicator that you're close to that point short of constantly checking SG?

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I guess it's just having some experience. I would wait about a week, then check the SG. If I'm close to 75% done, then I'd go ahead and do the diacetyl rest. If not, I'd guestimate when it would be about 75% done. The first time, it's a learning curve. The thing is, if you miss it and the beer is 85% done, it's not a big deal. Even if the beer is at FG, the yeast will still work and clean up the diacetyl; it just works better if it's still in active fermentation mode, that's all.

I do diacetyl rests when the krausen starts to fall. I don't check SG at that point. On an average of a 1.046 lager, I'm usually doing the D-rest sometime between day 6 and 8. You don't have to slowly raise the temp. Slow temp changes are only for reducing temps in lagers.

I can't vouch for all dry lager yeasts as I've only used Saflager W-34/70. This is allegedly the same strain as WLP-830 and Wyeast 2124. I have been very happy with the batch I've done with the W-34/70. But with all lager yeasts, pitch rate and wort temp are key. I pitched 2 re-hydrated packs at 50°F and have been very pleased as I've detected no esters or other off-flavors sometimes attributed to dry lager yeasts. I don't see me using a liquid lager yeast again anytime soon.

EDIT: Let me clarify my first statement. I raise the freezer control temp to do D-rests when the krausen is about 1/3 to 1/2 fallen. I let the freezer lid open for a few hours to help the beer reach the temperature quicker.

YooperBrew said:

I guess it's just having some experience. I would wait about a week, then check the SG. If I'm close to 75% done, then I'd go ahead and do the diacetyl rest. If not, I'd guestimate when it would be about 75% done. The first time, it's a learning curve. The thing is, if you miss it and the beer is 85% done, it's not a big deal. Even if the beer is at FG, the yeast will still work and clean up the diacetyl; it just works better if it's still in active fermentation mode, that's all.

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Yeh, 75% is a guideline. You don't want to do the majority of the fermentation at the higher temperature of a d-rest, but you don't want the fermentation to be completely finished either, because in theory the yeast wouldn't be active enough to eat up the diacetyl, although in reality this is unlikely.

That said, if you pitch enough (use a good calculator like Mr Malty) and you pitch below ferm temp and let it rise up to your ferm temp you won't need a D-rest. You may still do one though, but all conventional wisdom seems to state it would be unneccesary.

I do d-rests because i've had some difficulty getting below 50F in a timely manner. The BEST technique would be to get it to below ferm temp ASAP, in under an hour, but that's really hard for some people without a crazy good chiller, myself included.

menschmaschine said:

I pitched 2 re-hydrated packs at 50°F and have been very pleased as I've detected no esters or other off-flavors sometimes attributed to dry lager yeasts.

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Menschmaschine...when you rehydrate do you rehydrate in warm water, then cool to the pitching temp before pitching?

BruDaddy said:

Menschmaschine...when you rehydrate do you rehydrate in warm water, then cool to the pitching temp before pitching?

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I followed the Fermentis instructions... on their website in pdf form. It states to use water 10 times the weight of the yeast. So, if the yeast pack is 11.5g, 1 gram = 1 mL of water, so 115 mL per packet. I dumped two into 230 mL of preboiled, cooled water.

For temperature, it's 23°C or ~73°F. I took the yeast out of the fridge and let it warm up to room temp, then poured it onto water at around that temp and after it was rehydrated, cooled it to near pitching temps before pitching.

I don't think temperatures need to be exact... you just don't want to shock the yeast.