Substituting ale yeast for lager yeast

I can make a decent lager by fermening in my Michigan basement at about 45-50 degrees, which I figure is about the same thing as a German “keller” before refrigeration. The temp may change slightly a few degrees, but if it does it never goes over 52 and takes at least 24 hours to move 2 or 3 degrees. I then lager at around 35 degrees for 3 weeks.  I’ve made many dark lagers and they’ve turned out fine, but whenever I make a light German style “pils” I get one bad flavor or another. I make fine ales as well and when I substitute one ale yeast for another it doesn’t seem to make much difference, so I was going to try using my standard blond ale dry yeast (Sa-05) with the pilsener recipe. Can anyone give advice on what this will do?

Also: I’ve read that seperating the cold break from the boiled unfermented beer after 12 hours is standard among pros, but since I’ve never done this with an ale, I don’t do it with lagers. Could this be my problem? I hate to let beer sit without fermenting any longer than I have to!

It sounds like you have the perfect temperature environment for making lagers using lager yeast so I’d look at something else in your process other than the primary fermentation temperature.  What bad flavors are you getting with your lighter lagers?

I don’t think that removing the cold break is going to do much for you.  I’d go with your instinct on that and get the fermentation going as soon as possible.

I don’t do a diacetyl rest because I really don’t think I have the capability to do so. That may be the issue, however as I stated earlier, I make darker lagers and they seem fine. Maybe the flavors are there but covered up by darker stronger malts? I’m getting anything from a classic ‘buttery’ diacetyl flavor to other less appearent flavors of uhm…weeds I guess???

All you need to do for a diacetyl rest is to move your fermenters upstairs.

That was my first thought after reading your intital post.  Dark beers allow you to get away with a lot of things a lighter beer won’t allow.  The dark malts can cover up a multitude of flaws.  The flavors are probably there in all your brews but you can only detect them in the lighter ones.  More information about your brewing process would probably help figure out what might be going on.

Try a longer boil.  Pilsner malts are subject to DMS, but 90-120 minute uncovered boils help prevent DMS from forming.

I boil for 90 min anytime I use pilsner malt just to be safe.

If I move the fermenter upstairs wouldn’t the temperature rise be too fast? It would go from 50 to 65 in a few hours.

It may be a bit faster than optimum, but you should be fine, You have the thermal mass of 5 gallons of wort that will slow it down, put it by an outside wall to start.  The key is to reduce you diacetyl,

No, that wouldn’t be a problem. With my last Helles I employed a maturation rest at 72F for 3 days before I crashed it to 32 F.

My experience, however, has been that I rarely need the diacetyl/maturation rest for diacetyl reduction but for reaching the targeted FG. After fermenting the beer at 46-48 F for 2 weeks I don’t notice diacacetyl. Only a sulfury note.

At what wort temperature do you pitch the yeast?

Kai

I try to get it down to 45 before I pitch, but have pitched it as high as 60. I haven’t thought that the pitch temp was a problem because I usually don’t see any bubbling or activity for at least 24 hrs, by which time the temp is well below 50. Basically, I never see any activity until the temp is around 50, so I assumed the pitch temp didn’t matter all that much. Is this an incorrect assumption?

I don’t know how correct this assumption is, but based on statements from other home brewers there might be a connection between pitching temp and diacetyl production. Others should chime in on this.

Kai

It is the activity that occurs before you see fermentation that is often the cause of off-flavors.  As a rule, ALWAYS pitch below or at your fermentation temperature and allow the wort to warm up to your fermentation temps.  I know people that successfully ferment lagers at 55F so you are close.  When you can always ferment at the proper temp.

Time often eliminates the need to perform a diacetyl rest.  If you have diacetyl pitch some fresh yeast, don’t aerate, the fresh teast will consume the diacetyl.  Note that this is a corrective action and is not part of normal procedures.

Kai is far more familiar with lagers than I am.

Wow! Pitching fresh yeast is a great idea! Should I pitch it at around 50 degrees?

If you have diacetyl, I would bring your fermenter upstairs and pitch at about 60-65

If I do this then bring the temp back down to 50, wont the fermentation stop? Or do I just let fermentation finish at 60-65?

Let it finish fermenting at this temperature.

Kai

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Diacetyl has never been a problem in my lagers but I can not (and this is probably a lack of skill because traditional commercial producers do it) get the best attenuation without ramping up. This makes excellent lagers reliably.

On the issue of substituting ale yeast for lager yeast, I’ve been thinking about doing the opposite and making an IPA with lager fermentation (I know this is not a new idea) based on having the Mikkeller yeast series where I thought that what the Chico yeast does for hoppy beers (get out of the way of the hops) the lager yeast did much better.

You can wrap a couple blankets around it to slow the temperature rise.