Question re lagers ..

soccerdad

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So I've been doing this for nearly a decade, and I think I'm doing well - no, I know I'm doing well, but sometimes the science stumps me.

I have mostly brewed ales, but a few lagers here and there, and also building up supplies and equipment to brew what I want, when I want. Building up equipment means that I now have the capacity to maintain lower temps and the space to let beer sit for a few weeks. So I brewed a couple of lagers back and I knew how dynamite they would be. They're not.

NO off flavors, no yeast issues, nice clear beer. But too sweet. No sugar or honey or sweetener in either recipe.

I have two thoughts. 1) I used a single infusion mash. I wonder if I should step mash the lagers. Am I not getting all the fermentables from the mash? Would I get a drier, crisper beer if I rested at 125f and 148f? 2) What I hear about a diacetyl rest is to warm the beer as you near the end of fermentation and give it about 48 hours at about 68f. Then ferment it out fully at 55f before cold crashing. Could I be rushing the D rest? Am I interrupting the fermentation by going too quickly to the D rest, and therefore leaving sugars in the wort?

Are there other ideas that I am missing? Bueller? Anyone?
 
You never mentioned any gravity readings, so that leads me to think that you didn’t complete fermentation.
 
^^^That would be my thought. Attenuation is the likely culprit. If you're fermenting at lager-yeast temps, you'll want a big yeast count and plenty of aeration/oxygenation in the wort.
What I hear about a diacetyl rest is to warm the beer as you near the end of fermentation and give it about 48 hours at about 68f. Then ferment it out fully at 55f before cold crashing. Could I be rushing the D rest? Am I interrupting the fermentation by going too quickly to the D rest, and therefore leaving sugars in the wort?
The easiest and most effective way to do a D-rest is to get about 80% of the way through fermentation and raise to 68 or so and leave it until it's at final gravity. Further fermentation after D-rest could result in more diacetyl production and be counterproductive all the way around. Rushing in general is likely to be a problem. You don't mention whether you keg or bottle but assuming you keg, you could be lowering temp for crashing/lagering too early and leaving residual sugars.
If you bottle and it's carbing to the proper level without bombing, the fermentable sugar level is stable and it's something else.
If you're using a lot of Crystal malts (including Honey malt, Biscuit, etc) or things like Aromatic or Melanoidin malts, those will leave the impression of sweetness.
Without more specific information about recipe, gravity readings, etc, it's pretty hard to narrow it down.
 
As Mase says those numbers will be helpful. If you're hitting your numbers maybe you just prefer a more attenuated beer than your process will give you. When I'm doing the lighter quaffing beers I extend the mash at least 30 minutes to give the beta amalyse more time to work. That will prefer the temp on the lower side, but time's the main one for beta amalyse cutting up the maltose for me. I'll generally end up with an attenuation in the mid 80s that way and a beer that definitely tastes dry to me.
 
As mentioned, numbers would help the diagnosis but while we're waiting, here's how I get nice, well-attenuated, dry lagers: First, pitch as cool as you can reasonably get the wort. I know there's a body of lore out there that says it doesn't matter, I'll wait until I see some science. Second, ferment on the cool end for the first couple of days or, if you measure such things, the first third of the gravity. Then let the beer start warming slowly, say two degrees F per day. When you have a few gravity points left, let the beer warm to the mid 60's, I shoot for 68. That'll give you a dry, diacetyl-free lager.
 
Mashing lower should help. Yeast health is important, are you using yeast nutrient and aerating well? Lagers need more oxygen than ales, so what works for ales might not be sweating enough. Also what strain of yeast are you using? Pick one with a higher attenuation level if possible. A link to your recipe with mash and ferment schedule would help us give more answers.
 
I don't have my notes in front of me, but I think you guys have helped me nail it with doing the D rest incorrectly. I was more than half done with attenuation, but probably 60 or 65% rather than 80. Thanks.
 
Incomplete attenuation everything else was just right ignoring your D rest. Your yeast were happy as you didnt note any off flavours only sweetness. As above start cool for a few days then let free rise a degree or two per day or so towards end of fermentation this will help drive your attenuation and keep yeast in suspension to help clean up before your ramp back down to freezing. Leave at final D rest temp until stable FG is reached.
 
A lager that has a mild sweetness to the finish is not unusual. The numbers will shed some light in it, but will not always reveal why it’s sweet. Remember not to confuse maltiness with sweetness.

First mashing at a lower temperature is important, but the mash times also need to be extended, 90-120 minutes for the first rest at 144-145F is a good place to start. The grain you choose has an impact as well, Rahr pilsner malt will be less malty and less sweet than Weyermann pilsner and Bohemian pilsner will have a stronger malt flavor than both, leading some to taste a sweetness on the finish. Absolutely no crystal/caramel malts. Munich, Vienna, wheat are all fine, but not crystal/caramel unless you making a Dunkel or Baltic porter and even then the crystal/caramel malts are used sparsely. Also, don’t use dextrin malts for head retention, it comes off as sweet, white wheat is a better alternative for head retention.

Yeast strains will also allow the sweetness to creep up, WLP833 will accentuate the malt and will be slightly sweeter than WLP830. 34/70 is a good dry yeast to use, S23 will be slightly sweeter and fruity (I’m on record already as a hater of S23). A great mock lager can be made with Wyeast 1007 alt yeast, if fermented at 52F it will be pretty dry clean and still remain malty, WLP029 is a nice Kolsch yeast with a slightly tart finish, but is dry.

To avoid fruitiness, I pitch a lot of 830 (2.0 mill/degree Plato/mL) at 42-44F and let it rise to 45-46F, don’t be surprised to have lags times @ 24-36 hours. It sets at that temp until the Krausen starts to fall and then I raise the temperature to 62F or so in 2-3 days. This helps with diacetyl and I think it drys out the beer as well.

To brew a lager right is tough, but once you get it down you’ll be hooked.
 
Oddly .. the one that had just a hint of sweet did call for a small amount of c60 .. about 3 ounces. Then mostly Pilsner and Vienna. A little saurmalz for ph.

The one that I found overly sweet was Pilsner, Munich and a touch of wheat. Again, saurmalz, but only for ph - a few oundes.

My mash notes on both are incomplete, but I know my target was 148f and I would have monitored that closely for 60 minutes and then do some cleaning and tidying for 15 to 30 minutes. So total mash time would have been 75 to 90 minutes. I may try to adjust the mashing a bit just to be sure the grain gets some time at lower temps.

But I think I'll focus on the timing of the D rest. After hearing from you guys and reading a bit more, I think that is much more my issue.

BTW - time in the keg is helping too. Still sweet but quite palatable.

Thanks again for all your thoughts.

Mr Natch
 
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Oh yeah - one other thing. Yeast .. I used 34/70 and pitched at 50f. I figured exothermic activity would maybe heat it up to 55. Kept it there until I brought it out to rest at 65. One both batches I used a single 11g sachet, but they were 3.5 gallon batches ( for a 3g keg) so I am confident I wasn't under pitched.
 
All seems pretty straightforward, especially if you hydrated your yeast packets, but you don't mention your fermentation time or gravity readings. Those are pretty critical variables.

What was your OG? That yeast pitch for anything under 1.040 is quite adequate but even at 1.050 it starts to fall short. For a typical average lager of 1.052 OG, you'd want to pitch 1 1/2 packets to get to a proper lager pitch rate of 1.5 million cells per milliliter.

How many days/weeks did you ferment at the temps you listed? That yeast could take up to 2 weeks at 50F before it's attenuated enough to raise for D-rest. After the temp raise, it should finish out pretty quickly but if it's stalled, it could take quite a while to finish out.

What was your final gravity? An FG of 1.008 would be pretty ideal for a low- to mid-gravity lager but 1.010 or even 1.012 could give you a nice, fairly crisp-finishing beer. If you start to get to 1.014, it's very likely to be quite sweet and if you experience the dreaded 1.020 stall, it can be downright syrupy. :confused:
 
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