Im pretty new to lagers and my question is what gravity should you start the D rest…For example say you brewed a 1.050 beer and your target FG is 1.010 start the D rest at 1.020? Or at the very end of primary? I hear alot of different opinions on the subject
Generally speaking, before it’s complete so the yeast are not going dormant yet, but after the warmer temp won’t negatively effect flavor. I think your 1.020 idea would be fine. That’s about 75% done.
Cool so the 75% finished ramp the temp to 60’s for a few days then proceed to lagering…thank you
ramp up the temp until it’s done whether that is a few days or a couple weeks. let the beer guide you. When the gravity is stable and the beer tastes good then lager
Gotcha… right on thanks
75% is a good rule of thumb, sometimes I make sure I have at least 2 degrees Plato to go when I ramp up. Taste the beer to decide if you need more time at the elevated temperature.
I play it by ear with my lagers. I typically will start to bump up the temps a couple degrees F at a time when I first notice the krausen dropping back into the beer. That tells me the yeast have past their peak work time and need a bit more warmth to finish properly and clean up after themselves.
I’ll kick with what I have been doing with lagers:
pitch at 45-50f and hold there until day 5ish. bump 5 degrees every 12 hours (or so) until I get to 65. hold there until done and then back off 5 degrees every 12 hours (or so) until I’m at or around 32 and hold till there is space in a keg.
I would err on the side of being late than early though. If you pitched properly then you should typically not even need a D-rest. I bring my lagers up to 65 for 2-3 days then crash to 32 anyway. I played with stepping it up and down but came to find it made no difference that I could tell and took too much attention. YMMV.
Dave
Ramping up at 1020 would be the right course of action if you know that beer is going to reach FG at 1010 or less. If that beer stops on you in the teens then you may not have enough fermentation to rid yourself of diacetyl (or its precursors).
FWIW, just ran my helles lager though the process. pitched at 47F and held fermentation at 49-50F for almost 6 days, took a sample and had gone from 1.055 to 1.018, and i warmed part of sample, left part unwarmed, covered both and then when warm sample was back to room temp, uncovered and tasted.There was a very slight hint of diacetyl in the warmed sample. let it rise to 65F where i held for 2 days for d-rest. took reading just now, at 1.014 (likely done) and sample (warmed and compared to unwarmed) is 100% diacetyl free (at least to my ultra sensitive taste).
Have you noticed any O2/airlock liquid suckback when you are dropping the temps in this fashion or even when you are holding it at 32 until there is an available keg?
i have not noticed it. i generally use a little vodka in a freshly sanitized airlock when dropping down around freezing, because water freezes and 80 proof doesn’t so much.
Pull the cap and bubbler out and cover it with foil to avoid suck back.
in my experience, a D-rest of 3 to 5 degrees with about 25% to go is my goal. However, I have had many instances where I had to choose to bump up the temp early, or not at all due to having to travel out of town. I have found that anywhere after 50% done seems to give the same results.
The only other bit of advice I would give is even when you have a steady final gravity, you may need to leave the beer alone for another week or two. Taste the beer when you think it is done, and look at it too. I find that at 8 to 11 days, the beer is at a steady gravity, but still cloudy and depending on the yeast, I still detect diacetyl. The cloudy is yeast still in suspension doing what they need to do for the lager… dont cold crash yet if the yeast is still clouding the beer… let them do their work. Let the beer stay at the d-rest temp for up to another two to three weeks. (I have not had good results with the cool one or two degrees a day many people do).
I find that the yeast will settle out just fine given time, and time is what the yeast need to clean ther beer up.
This brings to mind that many seem to pay less attention on brew day and then fuss over that fermentor way too much. Some of my better beers were left alone at the end, because I had other things taking up my time. Maybe a good thing to do is just find something else to do for a week or two after terminal gravity.
^^^^^ I agree, Jim. At the home level, little or nothing bad (and usually something good) comes from leaving the beer on the yeast an extra week. I never have the byproducts in my beers that come from racking too soon. No coincidence.
I use an ‘S’ type airlock so no liquid suck back happens. air, I assume, does enter but I have not seen any ill effects from that. I have not brewed a very delicate light lager as of yet but I have brewed marzens that stood up just fine over the 1-3 month life of a batch, kolsch as well.
I missed the D rest window i think…it has been in primary since oct 23rd…i pulled a sample today( day 9) and i was at the target final gravity of 1010 already…I tasted it and i detect diacetyl…not a butter bomb but its there…I took it out of the chamber gonna let it rise to the 60’s…Is there still hope that the yeast will clean it up? i gave the fermenter a little swirl to rouse the yeast…Anything else i can or should do?
its going to be tough-just depends on how much of the yeast is still in suspension and working on your behalf. let it rise up to 65F and hold for 48 hours anyway. if you still detect it, you can make a small 1 liter starter and when it krausens, pitch it in. us-05 works well for this.