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General Category => General Homebrew Discussion => Topic started by: zman51 on March 21, 2018, 06:51:31 PM

Title: recirculate mash?
Post by: zman51 on March 21, 2018, 06:51:31 PM
Hey All,

I have been all grain for a while now and after mash time, I typically send that straight to brew kettle. I read a little about I should recirculate the mash a bit before sending to brew kettle? If true what is this doing?


thx

Z
Title: Re: recirculate mash?
Post by: yso191 on March 21, 2018, 06:59:23 PM
I *think* that is about setting the grain bed so it filters better.  I don't worry about it, I filter the wort coming out of the MT with a fine mesh bag.
Title: Re: recirculate mash?
Post by: mabrungard on March 21, 2018, 07:59:42 PM
There are lipids and other constituents that you don't want getting into your kettle and subsequent beer. It is highly recommended that you recirculate your wort until the discharge is clear. Turbid wort is a no-no.
Title: Re: recirculate mash?
Post by: Robert on March 21, 2018, 08:52:56 PM
There are lipids and other constituents that you don't want getting into your kettle and subsequent beer. It is highly recommended that you recirculate your wort until the discharge is clear. Turbid wort is a no-no.
+1
Title: Re: recirculate mash?
Post by: yso191 on March 21, 2018, 09:15:19 PM
There are lipids and other constituents that you don't want getting into your kettle and subsequent beer. It is highly recommended that you recirculate your wort until the discharge is clear. Turbid wort is a no-no.

What is the consequence to the beer if this is not done?
Title: Re: recirculate mash?
Post by: Robert on March 21, 2018, 09:47:55 PM
There are lipids and other constituents that you don't want getting into your kettle and subsequent beer. It is highly recommended that you recirculate your wort until the discharge is clear. Turbid wort is a no-no.

What is the consequence to the beer if this is not done?
Among other things, lipids lead to rapid oxidative staling and are detrimental to foam.  Bits of husk in the boil contribute to astringency due to  excess tannins, which also lead to rapid oxidative staling and haze.  These are just the big bullet points.  In short, clear wort is essential to fresh tasting, clear beer with good foam and mouthfeel.  The same goes for wort post-boil going into the fermenter; trub should be separated. I'm sure someone will elaborate.
Title: recirculate mash?
Post by: BrewBama on March 21, 2018, 10:57:15 PM
I use a fine mesh bag as well. The wort doesn’t get any cleaner between the moment I open the valve to recirculating fornever.


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Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 12:02:54 AM
I use a fine mesh bag as well. The wort doesn’t get any cleaner between the moment I open the valve to recirculating fornever.


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I lauter the conventional way with a false bottom.  I have to recirculate very briefly before it runs clear.  Many European breweries now filter the wort into and out of the boil.  I guess you guys with fine mesh are doing the same thing. As long as it runs clear, that's what matters.
Title: Re: recirculate mash?
Post by: Richard on March 22, 2018, 12:18:16 AM
What about people who Brew in a Bag? There is a mesh bag, perhaps fine or perhaps not, but not really any chance to see whether the wort is running clear or not. Same question applies to automated brewing systems which have metal mesh inserts for the grains.
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 12:31:01 AM
What about people who Brew in a Bag? There is a mesh bag, perhaps fine or perhaps not, but not really any chance to see whether the wort is running clear or not. Same question applies to automated brewing systems which have metal mesh inserts for the grains.
To me, this inability to guarantee crystal clear wort seems like a potentially fatal flaw in these systems.  I've never considered using them, but I guess you'd have to weigh your goals,  wort/beer quality vs. some other considerations, unless you can somehow get clear wort in these systems.  (Frankly I can't understand the apppeal of these things.  Conventional setup is cheaper, faster, and easier to clean up in my experience, and gives high quality and high efficiency.  But that's me.)
Title: Re: recirculate mash?
Post by: Big Monk on March 22, 2018, 12:40:04 AM
Among other things, lipids lead to rapid oxidative staling and are detrimental to foam.  Bits of husk in the boil contribute to astringency due to  excess tannins, which also lead to rapid oxidative staling and haze.  These are just the big bullet points.  In short, clear wort is essential to fresh tasting, clear beer with good foam and mouthfeel.  The same goes for wort post-boil going into the fermenter; trub should be separated. I'm sure someone will elaborate.

What about people who Brew in a Bag? There is a mesh bag, perhaps fine or perhaps not, but not really any chance to see whether the wort is running clear or not. Same question applies to automated brewing systems which have metal mesh inserts for the grains.
To me, this inability to guarantee crystal clear wort seems like a potentially fatal flaw in these systems.  I've never considered using them, but I guess you'd have to weigh your goals,  wort/beer quality vs. some other considerations, unless you can somehow get clear wort in these systems.  (Frankly I can't understand the apppeal of these things.  Conventional setup is cheaper, faster, and easier to clean up in my experience, and gives high quality and high efficiency.  But that's me.)

^^^
(THIS * 2) + infinity
Title: Re: recirculate mash?
Post by: tommymorris on March 22, 2018, 01:01:15 AM
I do BIAB with a bag. There are no husks in my wort. Not sure about lipids.
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 01:17:26 AM
I find very fine husk particles make it through even a well set grain bed.  They collect at the bottom of my "grant" (bucket the tube from lauter tun goes into) so I can carefully run the clear wort off into the kettle leaving them behind.  If your mesh bag is fine enough it might exclude them.  Other substances are fine and light enough they might squeeze through.  But they are also most effectively left as "top dough" on recirculation and excluded from a lautered wort.  Again, I don't know how effectively they might be filtered by a bag.  (Thise "malt pipes" would worry me.) You can always sample your wort in a glass.  If it's clear, good.  If it's at all cloudy, not so good.
Title: Re: recirculate mash?
Post by: tommymorris on March 22, 2018, 01:35:52 AM
I don’t own one, but, Grainfather and Robobrew recirculate. I have seen videos with people remarking about how clear the wort is.
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 01:50:45 AM
Whatever gets the job done.  Recirculation, filtering, whatever works, clear wort is what matters.
Title: Re: recirculate mash?
Post by: trapae on March 22, 2018, 04:03:04 AM
So we are really just talking about vorlaufing with a pump right? I recently went from vorlaufing with a false bottom to using a mesh bag inside SS Brewtech and using the false bottom as well.  I still Vorlauf with filling containers and pouring them back in. But I do have a pump and just realized I can Vorlauf by recirculating with the pump.   Currently, when I move wort to the kettle there are no particles but it is still cloudy.  I guess I should be vorlaufing much longer. I will start using my pump now.
How long are you guys recirculating before moving wort to the kettle to make it not cloudy?
Title: Re: recirculate mash?
Post by: klickitat jim on March 22, 2018, 04:33:47 AM
I vorlauf with my pump. For typical mash I start recirculation at about 45 min in. I recirculate a couple minutes just to ensure it's not terribly stratified and then I pull a small sample to verify I have reached expected °P. I only recirculate long enough to get clear runnings. Usually always have clear runnings by the time I read my refractometer  (couple minutes).
Title: Re: recirculate mash?
Post by: ynotbrusum on March 22, 2018, 11:38:08 AM
Continuous recirc with HERMS step mash here.  I used to use a sight glass to watch the wort clear.  Since it always ran gin clear, I gave up the sight glass as another thing to not have to clean.

The mash uses a basket that is perforated and my recirc is with a locline halo below the top of the liquid in the mash.  Brewtan B assures me of clear beer, too.
Title: Re: recirculate mash?
Post by: zman51 on March 22, 2018, 11:45:12 AM
Thanks for all the answers fellas. I am using a ss brewtech mashtun which has a real fine mesh false bottom. After reading, I think I will recirculate after mash time and I also use a fine mesh spider when pumping into brew kettle. Hopefully this will do a good job.

Z
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 11:56:28 AM
So we are really just talking about vorlaufing with a pump right? I recently went from vorlaufing with a false bottom to using a mesh bag inside SS Brewtech and using the false bottom as well.  I still Vorlauf with filling containers and pouring them back in. But I do have a pump and just realized I can Vorlauf by recirculating with the pump.   Currently, when I move wort to the kettle there are no particles but it is still cloudy.  I guess I should be vorlaufing much longer. I will start using my pump now.
How long are you guys recirculating before moving wort to the kettle to make it not cloudy?
I don't use a pump, just fill a pitcher and gently retjrnnto the top.  You only need to recirculate (ok vorlauf if you like) until the wort runs perfectly clear.  I have virtually zero dead space under my false bottom, so it's only a few quarts.  Your tun design, your grist, and other things will affect it, so there's no magic number for time.  Just whenever it's clear.  (I think a pump might make this harder.  Too fast a flow will keep drawing material down through the bed.  Gravity will allow the flow to set its own optimum.)
Title: Re: recirculate mash?
Post by: Big Monk on March 22, 2018, 12:11:56 PM
Just whenever it's clear.  (I think a pump might make this harder.  Too fast a flow will keep drawing material down through the bed.  Gravity will allow the flow to set its own optimum.)

It goes without saying that if you use a pump you need to throttle it on the output. A valve works as well as electrically controlling it.

Title: Re: recirculate mash?
Post by: klickitat jim on March 22, 2018, 01:23:34 PM
Just whenever it's clear.  (I think a pump might make this harder.  Too fast a flow will keep drawing material down through the bed.  Gravity will allow the flow to set its own optimum.)

It goes without saying that if you use a pump you need to throttle it on the output. A valve works as well as electrically controlling it.
Yup. I bought a decent stainless head this winter and immediately started getting stuck. It is possible to suck the grain bed down and get stuck. Prime with gravity, then close the valve and turn pump on. I throttle open just enough to get a gentle stream.
Title: Re: recirculate mash?
Post by: gman23 on March 22, 2018, 01:27:33 PM
Interesting. I used to use a false bottom and would vorlauf until I got clear runnings. Now I use a bag without vorlauf as others have mentioned and have had zero noticeable difference in the finished beer. Thanks for the information. Glad it doesn't perceptibly affect my beer.
Title: Re: recirculate mash?
Post by: klickitat jim on March 22, 2018, 01:46:27 PM
I think if your wort is unclear it's important to know why. If it's because it's full of starch, that's maybe a problem. I'm not calling anyone out here, I could be totally misunderstanding something. Doesn't pH have to be above 6 to extract tannins from husks? If so, husks are not an issue at mash temp. If they are an issue at 212F then... I guess that is my excuse to not do decoction.

Usually my wort is clear. Usually not Crystal clear. I try not to transfer grain solids to the boil, but I don't inspect every drop. If it's fully converted, I'm happy. All I know is I never have a tannin astringent issue, or a final beer clarity issue, or a foam issue. And after boil i just pump gnarly unsettled wort to the fermentor. In the past I would let it settle and be all OCD about clear wort to the fermentor. I'm seeing no change in final quality between the two. I have become slightly more OCD about cold side O2. Maybe that's what makes the difference.
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 02:16:22 PM
I think if your wort is unclear it's important to know why. If it's because it's full of starch, that's maybe a problem. I'm not calling anyone out here, I could be totally misunderstanding something. Doesn't pH have to be above 6 to extract tannins from husks? If so, husks are not an issue at mash temp. If they are an issue at 212F then... I guess that is my excuse to not do decoction.

Usually my wort is clear. Usually not Crystal clear. I try not to transfer grain solids to the boil, but I don't inspect every drop. If it's fully converted, I'm happy. All I know is I never have a tannin astringent issue, or a final beer clarity issue, or a foam issue. And after boil i just pump gnarly unsettled wort to the fermentor. In the past I would let it settle and be all OCD about clear wort to the fermentor. I'm seeing no change in final quality between the two. I have become slightly more OCD about cold side O2. Maybe that's what makes the difference.

Tannins are extracted at a higher pH  in the mash, true, but if grain solids get into the boil, well at boiling temp they'll be extracted readily at any pH.* There is a  longstanding question of how clear is clear enough, both into the boil and into the fermenter.  The best consensus seems to be, pretty clear.  Crystal clear is probably not necessary, but the kind of clarity you and I probably get, Jim, is easily achieved and very beneficial.  (Like beer that hasn't quite fallen bright.  Looks crystal clear until closer inspection.)  It's a balance like HSA.  Don't be OCD, but don't gratuitously disregard sound practices when quality of beer can be significantly impacted. I guess we're striking the right balance if our results are good.

*(And then you bring up decoction.  I avoid invoking that as evidence for or against anything when talking modern processes like we use.  I think decoction has to be seen as part of a whole set of processes that evolved to mitigate each other's faults.  Like maybe X isn't a problem in decoction if it's offset by Y happening in six months lagering at 2°C.  And boiling the decoction eliminates HSA,  which may affect the equilibrium of the whole system.  It just may all be irrelevant to us.  Could read Noonan again, or I could just exercise reasonable care.)
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 04:40:16 PM
^^^^
"It's a balance like HSA."

I should just point out the obvious, that this actually all goes together.  To avoid staling and haze, you minimize substances susceptible to oxidation, and minimize opportunities for oxidation.   You address the whole complex of lipids & polyphenols + O2 both hot & cold side + time & temperature, and try to keep the whole system below the threshold where it becomes a problem. If you could totally eliminate two legs of the triangle, the last wouldn't matter, but in practice you do what you can for each.  Have clear wort, minimize O2, keep beer cold and drink beer fresh.  The less you can control one parameter, the more critical the others.
Title: Re: recirculate mash?
Post by: ynotbrusum on March 22, 2018, 10:49:08 PM
And so, I gotta ask the logical extension of the foregoing - do you skim break materials?  And do you use an immersion whirlpool chiller? 
Title: Re: recirculate mash?
Post by: klickitat jim on March 22, 2018, 10:53:26 PM
And so, I gotta ask the logical extension of the foregoing - do you skim break materials?  And do you use an immersion whirlpool chiller?
Me? No skim, yes immersion chiller.
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 11:24:38 PM
And so, I gotta ask the logical extension of the foregoing - do you skim break materials?  And do you use an immersion whirlpool chiller?

Not sure what you mean by skim break material.  The foam on the boil is very clean, and anything there is sticks to the collar of the kettle.  Yes, immersion chiller, settle 20-30 min and rack off of all hot and cold break taking (practically) crystal clear wort to the fermenter. There is very, very little trub in the fermenter when I harvest yeast.
Title: Re: recirculate mash?
Post by: klickitat jim on March 22, 2018, 11:29:50 PM
And so, I gotta ask the logical extension of the foregoing - do you skim break materials?  And do you use an immersion whirlpool chiller?

Not sure what you mean by skim break material.  The foam on the boil is very clean, and anything there is sticks to the collar of the kettle.  Yes, immersion chiller, settle 20-30 min and rack off of all hot and cold break taking (practically) crystal clear wort to the fermenter. There is very, very little trub in the fermenter when I harvest yeast.
Harvesting yeast! Main reason I can see for limiting boil kettle trub to the fermentor.

Another reason would be if I was brewing 10bbl at a time. If I could prevent a bbl of boil trub from getting through, I would. But at my 1/5th bbl size, I only end up with a thin line of boil trub in the bottom of my fermentor. For me... not a problem.
Title: Re: recirculate mash?
Post by: Robert on March 22, 2018, 11:45:59 PM
And so, I gotta ask the logical extension of the foregoing - do you skim break materials?  And do you use an immersion whirlpool chiller?

Not sure what you mean by skim break material.  The foam on the boil is very clean, and anything there is sticks to the collar of the kettle.  Yes, immersion chiller, settle 20-30 min and rack off of all hot and cold break taking (practically) crystal clear wort to the fermenter. There is very, very little trub in the fermenter when I harvest yeast.
Harvesting yeast! Main reason I can see for limiting boil kettle trub to the fermentor.

Another reason would be if I was brewing 10bbl at a time. If I could prevent a bbl of boil trub from getting through, I would. But at my 1/5th bbl size, I only end up with a thin line of boil trub in the bottom of my fermentor. For me... not a problem.

Supposedly a little cold break can nourish yeast, but wort should be nutritious enough as is.  The hot break has the majority of the  nasty lipids and such, so you want to settle long enough to remove that (it's bigger, heavier particles, so easy enough to leave in the kettle with the hop material.)
Likewise, if you swirl up the yeast in your fermenter and let it sit 5 min, you can pour the yeast off the heaviest trub if you do have some.
Title: Re: recirculate mash?
Post by: Robert on March 23, 2018, 12:05:39 AM
All of this reminds me of my longstanding impression that making beer is kind of an endless series purifications,  removing stuff until only the beer is left.  Lautering, hot break, cold break, yeast settling, chill haze precipitation, fining, maybe filtering....Like the story of Michaelangelo removing all the obscuring rock until only David was left!
Title: Re: recirculate mash?
Post by: ynotbrusum on March 23, 2018, 06:12:12 PM
All of this reminds me of my longstanding impression that making beer is kind of an endless series purifications,  removing stuff until only the beer is left.  Lautering, hot break, cold break, yeast settling, chill haze precipitation, fining, maybe filtering....Like the story of Michaelangelo removing all the obscuring rock until only David was left!


Truth, Robert!  Except I think the beer can still be quite satisfactory with a slight blemish or two leading up to fermentation, because the yeast make the final chisel strokes before the polishing strokes of fining.

Cheers.
Title: Re: recirculate mash?
Post by: narcout on March 23, 2018, 07:50:34 PM
Here are a few interesting excerpts from TB&M.  The first concerns lautering and the last two are about post-boil wort.

(http://i240.photobucket.com/albums/ff164/narcout/aa_2.jpg) (http://s240.photobucket.com/user/narcout/media/aa_2.jpg.html)

(http://i240.photobucket.com/albums/ff164/narcout/bb_1.jpg) (http://s240.photobucket.com/user/narcout/media/bb_1.jpg.html)

(http://i240.photobucket.com/albums/ff164/narcout/cc.jpg) (http://s240.photobucket.com/user/narcout/media/cc.jpg.html)
Title: Re: recirculate mash?
Post by: Robert on March 23, 2018, 08:02:43 PM
Note that Kunze does make clear that hot break must be _completely_ removed in order for any cold break material passing into fermentation to be acceptable.  German brewers are able to do this by means of filtration of the hot wort before chilling.  For homebrewers, it is not possible to separate the processes.  So for us, having to remove the break material all at once after chilling, the only option is to remove as much of the combined break material as possible.
Title: Re: recirculate mash?
Post by: mabrungard on March 23, 2018, 11:36:03 PM
For homebrewers, it is not possible to separate the processes. 

Not necessarily true. My kettle has a circumferential wort pickup with a steel braid over it that serves as a good filter. I employ this since I pump from the kettle to my plate chiller. That wort is crystal clear coming from the kettle.
Title: Re: recirculate mash?
Post by: Robert on March 24, 2018, 12:06:09 AM
For homebrewers, it is not possible to separate the processes. 

Not necessarily true. My kettle has a circumferential wort pickup with a steel braid over it that serves as a good filter. I employ this since I pump from the kettle to my plate chiller. That wort is crystal clear coming from the kettle.
I stand corrected.  For those of us who cannot do this, the prudent thing is to remove all break material.  The possible benefits of a little cold break in the fermenter are slim compared to the real detriment of hot break or possibly too much cold break.

EDIT Actually I used to have a pretty effective filter at my disposal.   Whole cone hops!  Then a few years ago I admitted resistance was futile, and followed the rest of the world into pellets.
Title: Re: recirculate mash?
Post by: trapae on March 24, 2018, 12:46:28 AM
 So is the consensus something like this? ( as far as there can ever ever be a consensus in homebrewing )

 First and second runnings should be as clear as possible.

 Remove ALL of hotbreak.

 Remove as much as possible of cold break?

 How are people effectively removing hotbreak, a fine strainer?
 Also, Martin, where did you get your circumferential wort pick up contraption? Or did you make it?

Title: Re: recirculate mash?
Post by: Robert on March 24, 2018, 01:26:37 AM
Looks like you've summed up the takeaway pretty well.  The easiest way to remove break, especially the heavier hot break, is to settle and rack off the sediment.   I use an immersion chiller and settle for 20-30 min and can rack off virtually crystal clear wort. If you chill with a cf or plate rig you could use a settling tank, an intermediate vessel on the way to the fermenter, to remove all break, or at least settle the hot break before carefully racking through your chiller (or figure out some kind of hot break filter like Martin.  I'd like to see a pic of his!)  Hot break is coarser and heavier than cold break, so removing it is easier.
Title: Re: recirculate mash?
Post by: BrewBama on March 24, 2018, 10:49:39 PM

EDIT Actually I used to have a pretty effective filter at my disposal.   Whole cone hops!  Then a few years ago I admitted resistance was futile, and followed the rest of the world into pellets.

I think I am going to order whole hops for my next brew. That way I don’t have to knife my laugh.


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Title: Re: recirculate mash?
Post by: klickitat jim on March 24, 2018, 11:02:57 PM
I need a pint of beyond hazy Knee-Pa called Knife My Laugh! Milkshake doesn't even describe the level of haze thickness. Cheesy with haze. It's basically a hoppy custard!
Title: Re: recirculate mash?
Post by: mabrungard on March 25, 2018, 03:22:09 PM
OK, I placed a new thread and discussion for the peripheral wort intake that I use, at the following location:

https://www.homebrewersassociation.org/forum/index.php?topic=31436.0 (https://www.homebrewersassociation.org/forum/index.php?topic=31436.0)
Title: Re: recirculate mash?
Post by: Robert on March 25, 2018, 03:49:36 PM
Supposedly a little cold break can nourish yeast, but wort should be nutritious enough as is. 

Just listened to MBAA podcast where Stone did experiments and found that any trub carried over into the fermenter actually had a significant ADVERSE effect on yeast health and fermentation.
Title: recirculate mash?
Post by: tommymorris on March 25, 2018, 04:07:21 PM
Supposedly a little cold break can nourish yeast, but wort should be nutritious enough as is. 

Just listened to MBAA podcast where Stone did experiments and found that any trub carried over into the fermenter actually had a significant ADVERSE effect on yeast health and fermentation.
That seems to conflict with some of the text scanned from some book that someone put in this thread.
Title: Re: recirculate mash?
Post by: Robert on March 25, 2018, 05:03:04 PM
Supposedly a little cold break can nourish yeast, but wort should be nutritious enough as is. 

Just listened to MBAA podcast where Stone did experiments and found that any trub carried over into the fermenter actually had a significant ADVERSE effect on yeast health and fermentation.
That seems to conflict with some of the text scanned from some book that someone put in this thread.
That's Prof Kunze, Technology Malting and Brewing, the standard textbook, and it's the conventional textbook wisdom.  So the Stone experiment surprised me.  I suppose we don't know all the other factors in their system that might contribute.  But it's an interesting piece of evidence, though perhaps no more conclusive than a Brulosophy xBmt.  Stone didn't continue with extensive experiments once they concluded it was affecting their yeast.  They saw no other adverse effects on the beer.