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General Category => General Homebrew Discussion => Topic started by: Wort-H.O.G. on May 17, 2013, 01:28:29 PM

Title: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 01:28:29 PM
Started brewing lagers about 4 months ago - so very new to it. Im trying to figure out how and when to perform the diacetyl rest. its my understanding all lagers will produce diacetyl - how much depends on temp, yeast, etc, and how much you personally detect in smell or taste depends upon your sensitivity to diacetyl. for me personally, i can detect the taste or smell even in small amounts - and even if the slick feeling people describe isn't present. Ive read people letting the lager finish up at about 2 weeks, and then let it rise to about 60F. i'm somewhat curious about this practice, as my understanding is by that point fermentation is completed and would seem there's not as much yeast in suspension that are active enough to clean up diacetyl (??).

I currently have a 1.052 pilsner and 1.053 vienna lager that have been fermenting for 6 days at 49-50F (i pitched yeast at 48F wort). the krausen has dropped and is starting to settle. i really don't want to pull the airlock and release the co2 to take a hydrometer reading - so wondering if there's a method anyone uses to determine when to do the d-rest? i'm leaning towards waiting for krausen to drop, and then around day 10 let the temp rise to about 60F for 48 hours or burnout, then slowly bring it down to 45F before lagering - -thoughts??
Title: Re: timing a lager D-rest
Post by: klickitat jim on May 17, 2013, 01:34:42 PM
I'm new too but no D yet. I run at 50 till I drop below 1.020 which I test around 7-10 days in. Once below 1.020 I walk it up to 60 for a few days. When my FG is reached I do a day at 68, boil point for D. Then drop to lager temp.
Title: Re: timing a lager D-rest
Post by: davidgzach on May 17, 2013, 01:39:34 PM
Everything above looks correct except that "all lagers will produce diacetyl".  Not all strains will produce diacetyl and it will mainly depend upon whether you pitch the correct amount of yeast and the fermentation temperature.

That aside, your plan is sound.  IMHO, a D-Rest is mainly insurance if you pitched and fermented correctly.  You may not need one at all, but it will not hurt your beer either. 

I typically wait until I see little to no activity and then raise it up(given an active fermentation).  Others have different processes.  This works for me without having to take numerous gravity readings.

Dave

Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 01:42:43 PM
Everything above looks correct except that "all lagers will produce diacetyl".  Not all strains will produce diacetyl and it will mainly depend upon whether you pitch the correct amount of yeast and the fermentation temperature.

That aside, your plan is sound.  IMHO, a D-Rest is mainly insurance if you pitched and fermented correctly.  You may not need one at all, but it will not hurt your beer either. 

I typically wait until I see little to no activity and then raise it up(given an active fermentation).  Others have different processes.  This works for me without having to take numerous gravity readings.

Dave

Maybe someone else can weigh in, but seems to me diacetyl is always produced - just at different levels??
Title: Re: timing a lager D-rest
Post by: tygo on May 17, 2013, 01:43:02 PM
I wouldn't worry about pulling the airlock to take a gravity reading.  It's still fermenting and producing CO2.  Wait until its 4 or 5 points above your projected final gravity and ramp it up.

Although I usually don't bother taking a reading anymore since I usually just wait until it visually starts to look like it's getting towards the end and then ramp it up. 

I tend to do a D-rest on all of my lagers even though it's not strictly necessary just to be on the safe side and to ensure it attenuates all the way.
Title: Re: timing a lager D-rest
Post by: davidgzach on May 17, 2013, 01:53:06 PM
Everything above looks correct except that "all lagers will produce diacetyl".  Not all strains will produce diacetyl and it will mainly depend upon whether you pitch the correct amount of yeast and the fermentation temperature.

That aside, your plan is sound.  IMHO, a D-Rest is mainly insurance if you pitched and fermented correctly.  You may not need one at all, but it will not hurt your beer either. 

I typically wait until I see little to no activity and then raise it up(given an active fermentation).  Others have different processes.  This works for me without having to take numerous gravity readings.

Dave

Maybe someone else can weigh in, but seems to me diacetyl is always produced - just at different levels??

Yes, misstated.  It is always produced but a healthy fermentation will allow the yeast to re-absorb it before FG, some better than others.  Definitely at different levels.

Dave 
Title: Re: timing a lager D-rest
Post by: hoser on May 17, 2013, 01:54:32 PM
If you pitch enough healthy yeast, pitch slightly cooler than ferment temps, and maintain a constant, steady temp in the 48-52F range for 3-4 weeks (allowing the yeast to reabsorb fermentation by-products), then a D-rest isn't needed IMHO.

I make plenty of lagers and I am sensitive to diacetyl and I have never found diacetyl in my lagers post fermentation. 

Just my opinion.
Title: Re: timing a lager D-rest
Post by: theDarkSide on May 17, 2013, 01:56:07 PM
I pitch cold (45F) and let it free rise and hold at 50F.  Near the end of fermentation, I may raise it 5 degrees or so for a couple days.  I am a believer if you pitch cold, diacetyl is minimized, requiring only a minimal D-rest. 

I've done about 6 lagers, entered a few of them in several competitions and never got any feedback regarding diacetyl.

Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 01:57:42 PM
Everything above looks correct except that "all lagers will produce diacetyl".  Not all strains will produce diacetyl and it will mainly depend upon whether you pitch the correct amount of yeast and the fermentation temperature.

That aside, your plan is sound.  IMHO, a D-Rest is mainly insurance if you pitched and fermented correctly.  You may not need one at all, but it will not hurt your beer either. 

I typically wait until I see little to no activity and then raise it up(given an active fermentation).  Others have different processes.  This works for me without having to take numerous gravity readings.

Dave

Maybe someone else can weigh in, but seems to me diacetyl is always produced - just at different levels??

Yes, misstated.  It is always produced but a healthy fermentation will allow the yeast to re-absorb it before FG, some better than others.  Definitely at different levels.

Dave

understood.  I'm generally opposed to popping the airlock and taking a reading - i've proved out i can trust my process and fermentation always takes off (within 12 hours for ales, 12-18 hours for lagers) for ales and lagers alike, and finishes up as expected. i pitch appropriate quantities of yeast, and always use oxygen.
Title: Re: timing a lager D-rest
Post by: davidgzach on May 17, 2013, 01:59:30 PM
^^^^^^^Sounds good.  I would go with your plan.

Dave
Title: Re: timing a lager D-rest
Post by: udubdawg on May 17, 2013, 02:27:33 PM
with "normal" size lagers it is always somewhere in the day 5-7 range for me.  6 being the most common.  I understand not wanting to open it to take a reading, but there is something to be said for understanding your whole process.  I rarely check gravity anymore, because I used to, and now know "when I see this, I raise the temp"

...I suspect it is ready for the d-rest, ignoring whether it even needs one.

good luck--
--Michael
Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 03:00:39 PM
with "normal" size lagers it is always somewhere in the day 5-7 range for me.  6 being the most common.  I understand not wanting to open it to take a reading, but there is something to be said for understanding your whole process.  I rarely check gravity anymore, because I used to, and now know "when I see this, I raise the temp"

...I suspect it is ready for the d-rest, ignoring whether it even needs one.

good luck--
--Michael

i agree . ive noticed a repeatable pattern in time it takes the start of fermentation and time it starts winding down. i also pitch 45-48F, plenty of yeast, oxygen.  for 1.045-1.055, they generally take off at around 18 hours (+- 4) and noticeable activity finishing up around day 7-10. that's when i'm likely to let it rise on its own to around 60F.
Title: Re: timing a lager D-rest
Post by: denny on May 17, 2013, 03:56:43 PM
Everything above looks correct except that "all lagers will produce diacetyl".  Not all strains will produce diacetyl and it will mainly depend upon whether you pitch the correct amount of yeast and the fermentation temperature.

That aside, your plan is sound.  IMHO, a D-Rest is mainly insurance if you pitched and fermented correctly.  You may not need one at all, but it will not hurt your beer either. 

I typically wait until I see little to no activity and then raise it up(given an active fermentation).  Others have different processes.  This works for me without having to take numerous gravity readings.

Dave

Maybe someone else can weigh in, but seems to me diacetyl is always produced - just at different levels??

Diacetyl is always produced AFAIK but some yeasts are better at getting rid of it than others.  I don't think I've ever needed a diacetyl rest with WY2206.  Same with 2124 now that I think about it.  If I don't smell or taste diacetyl, I don't bother with a rest. 
Title: Re: timing a lager D-rest
Post by: theDarkSide on May 17, 2013, 04:01:06 PM
Diacetyl is always produced AFAIK but some yeasts are better at getting rid of it than others.  I don't think I've ever needed a diacetyl rest with WY2206.  Same with 2124 now that I think about it.  If I don't smell or taste diacetyl, I don't bother with a rest.

I use 2124 (or WLP830) for all my lagers...maybe that's why I never have any issue.
Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 05:43:28 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.
Title: timing a lager D-rest
Post by: denny on May 17, 2013, 06:12:42 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.
Title: Re: timing a lager D-rest
Post by: davidgzach on May 17, 2013, 06:15:19 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

+1.  You may get a little extra attenuation as well as was previously stated.

Dave
Title: Re: timing a lager D-rest
Post by: hopfenundmalz on May 17, 2013, 07:10:47 PM
The yeast should run the brewery, not the calendar. I take samples off of the raking arm in the conical. When the beer has about 2 Plato to go, it gets ramped up in the D-rest. This is in the 4-6 day range for a 1.050 lager. 2 days at higher temp and it is done. Taste it to be sure.
Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 07:37:15 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other
Title: timing a lager D-rest
Post by: denny on May 17, 2013, 07:50:33 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other

In my opinion and experience, no difference and no benefit.  AFAIK, the recommendation to do the rest earlier comes from commercial practices to speed up the process.  Fortunately, we're homebrewers.
Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 07:58:18 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other

In my opinion and experience, no difference and no benefit.  AFAIK, the recommendation to do the rest earlier comes from commercial practices to speed up the process.  Fortunately, we're homebrewers.

ha! love it denny - always get down an dirty answer from you.  ;D
Title: Re: timing a lager D-rest
Post by: hopfenundmalz on May 17, 2013, 08:17:43 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other
If you do it at 80%, the yeast will finish the sugars and be active to reduce the VDKs. The increased activity will help scrub off sulfur. Then you can crash down to cold temps to lager and drop out the haze and yeast. The classic profile has a slow cooling to keep the yeast working, as they will slowly reduce the VDKs at low temperature. 

So you clean it up, blow off sulfur and save time. If you are a homebrewer that brews lagers when the weather allows, saving time in the fermenter is a good thing. Might have to get another freezer someday so I can do lagers in the summer.
Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 08:39:23 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other
If you do it at 80%, the yeast will finish the sugars and be active to reduce the VDKs. The increased activity will help scrub off sulfur. Then you can crash down to cold temps to lager and drop out the haze and yeast. The classic profile has a slow cooling to keep the yeast working, as they will slowly reduce the VDKs at low temperature. 

So you clean it up, blow off sulfur and save time. If you are a homebrewer that brews lagers when the weather allows, saving time in the fermenter is a good thing. Might have to get another freezer someday so I can do lagers in the summer.

awesome info guys -another productive day at the forum.

i feel like i should be paying someone - who should i make the check out to? ;D
Title: timing a lager D-rest
Post by: denny on May 17, 2013, 09:11:03 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other
If you do it at 80%, the yeast will finish the sugars and be active to reduce the VDKs. The increased activity will help scrub off sulfur. Then you can crash down to cold temps to lager and drop out the haze and yeast. The classic profile has a slow cooling to keep the yeast working, as they will slowly reduce the VDKs at low temperature. 

So you clean it up, blow off sulfur and save time. If you are a homebrewer that brews lagers when the weather allows, saving time in the fermenter is a good thing. Might have to get another freezer someday so I can do lagers in the summer.

awesome info guys -another productive day at the forum.

i feel like i should be paying someone - who should i make  ;Dthe check out to?

Me, of course!  ;)
Title: Re: timing a lager D-rest
Post by: Wort-H.O.G. on May 17, 2013, 10:10:11 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other
If you do it at 80%, the yeast will finish the sugars and be active to reduce the VDKs. The increased activity will help scrub off sulfur. Then you can crash down to cold temps to lager and drop out the haze and yeast. The classic profile has a slow cooling to keep the yeast working, as they will slowly reduce the VDKs at low temperature. 

So you clean it up, blow off sulfur and save time. If you are a homebrewer that brews lagers when the weather allows, saving time in the fermenter is a good thing. Might have to get another freezer someday so I can do lagers in the summer.

awesome info guys -another productive day at the forum.

i feel like i should be paying someone - who should i make  ;Dthe check out to?

Me, of course!  ;)

Done!  seriously, my lagers have improved significantly since my schooling with you - much thanks bud. i also think i would be a very tough judge when it comes to diacetyl - my olfactory senses pick up the slightest trace, and as i've said before, i cant stand it.
Title: timing a lager D-rest
Post by: denny on May 17, 2013, 10:18:51 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other
If you do it at 80%, the yeast will finish the sugars and be active to reduce the VDKs. The increased activity will help scrub off sulfur. Then you can crash down to cold temps to lager and drop out the haze and yeast. The classic profile has a slow cooling to keep the yeast working, as they will slowly reduce the VDKs at low temperature. 

So you clean it up, blow off sulfur and save time. If you are a homebrewer that brews lagers when the weather allows, saving time in the fermenter is a good thing. Might have to get another freezer someday so I can do lagers in the summer.

awesome info guys -another productive day at the forum.

i feel like i should be paying someone - who should i make  ;Dthe check out to?

Me, of course!  ;)

Done!  seriously, my lagers have improved significantly since my schooling with you - much thanks bud. i also think i would be a very tough judge when it comes to diacetyl - my olfactory senses pick up the slightest trace, and as i've said before, i cant stand it.

Man, that's both a blessing and a curse!  I usually get a slickness on the roof of my mouth before I can taste it.
Title: Re: timing a lager D-rest
Post by: davidgzach on May 18, 2013, 12:51:42 PM
good info from everyone. seems like we are all on the same page. it just seemed odd to me to hear people do a d-rest after 2 weeks at 50F...seems all activity would be done and there would be nothing gained from doing a d-rest then (considering a normal lager range around 1.050-055). maybe for bigger beers over 1.060 there would still be fermentation activity near the 2 week mark - i just haven't done a lager that big.

As long as you don't remove the yeast from the beer, it doesn't matter if all activity has ended.  Warming the beer for the d rest will make it active again.

ok good to know. but then whats the difference in doing a d-rest at 80-85% attenuation , vs. 99-100% attenuation ? any benefit of one over the other
If you do it at 80%, the yeast will finish the sugars and be active to reduce the VDKs. The increased activity will help scrub off sulfur. Then you can crash down to cold temps to lager and drop out the haze and yeast. The classic profile has a slow cooling to keep the yeast working, as they will slowly reduce the VDKs at low temperature. 

So you clean it up, blow off sulfur and save time. If you are a homebrewer that brews lagers when the weather allows, saving time in the fermenter is a good thing. Might have to get another freezer someday so I can do lagers in the summer.

That's a good synopsis Jeff.  I was lucky to have my bro-in-law donate a chest freezer to the cause.  I have 4x5G in there at all times at 50F.   Mostly German Lagers.  I brew 10G on Saturday and Sunday, typically raise to 65F for 3 days after a week and then reduce 5F per day to 32F.  I'll leave them on the cake for 3 weeks, then keg and lager in a separate fridge.  My wife has been very kind to let me have two appliances in the garage solely for brewing.  I store all of my bulk hops in the top freezer of the lagering fridge and all of my washed yeast in the door compartments.  Works out real well and I can brew lagers year round.  You've got to get that freezer!