Author Topic: overnight HERMS  (Read 1062 times)

Offline soymateofeo

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overnight HERMS
« on: May 12, 2018, 03:51:35 PM »
Hey Team!   I have heard of people mashing overnight but was wondering about the 2 options.
1. mashing in a cooler with the lid on and cover with a blanket.
2. mashing and recirculating all night through my herms coil.

I want to do it #2 style because recirculating has increased my conversions and efficiencies tremendously but I have never done it for 8 hours. Is my chugger pump ok for that amount of time? Is there anything else I should be concerned about?

Offline jjpeanasky

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Re: overnight HERMS
« Reply #1 on: June 10, 2018, 11:22:29 AM »
The only thing I would be worried about with the pump is it overheating. Make sure it has ample space or air movement around it. However, I will say that I don't believe those pumps were designed to be ran continuously for that long.

With the HERMS system and the recirculation, you're going to use a lot more energy to keep temperature up vs. just mashing in the cooler and adding insulation (blanket). Most mashing is complete within 60-90 minutes anyways, the overnight part is just to break up the brewday. I would say as long as you can keep the mash above sour bug range (>110F) you'll be fine no matter which way you go, and even then that's not a lot of time for souring to happen.

Offline ynotbrusum

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Re: overnight HERMS
« Reply #2 on: June 10, 2018, 12:08:30 PM »
I have wondered about the same thing.  With an electric system, it should be negligible extra costs, so that part is not an issue to me.  Rather, the extended mash time could seemingly alter the pH as the grain is “re-rinsed” over an extended time period following conversion.  I have no science on that, but it stands to reason that the active heating of the mash combined with the amount of liquid overall passing through the grainbed might be a source of problems, at least potentially.  I would say it is ripe for an experiment! 

Other concerns are evident with an unattended process- pump failure, overheating the herms tun (boil out), etc...but you might be able to set alarms for that.
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Offline EHall

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Re: overnight HERMS
« Reply #3 on: June 12, 2018, 08:46:22 PM »
I can say as someone who does overnight mashes in a cooler, you don't need a blanket. You only lose maybe 5 degrees in 8-10hrs. you're not going to notice that in the finished product.
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Offline old.va.brewer

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Re: overnight HERMS
« Reply #4 on: June 17, 2018, 12:44:37 PM »
Mash over night with a thermo control in the mash. The pump and heat only comes on when needed.
Make sure your volume in the tun is always above the grain bed, during circulation. Your going to have to watch the ph with 8 hour of mashing, but if you keep your temps constant that will help.
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Offline drewer02

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Re: overnight HERMS
« Reply #5 on: June 18, 2018, 02:59:08 AM »
The thermo control seems will play important role in ensuring the right temp. Update us with your result.

Offline David

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Re: overnight HERMS
« Reply #6 on: June 20, 2018, 11:12:30 PM »
I can say as someone who does overnight mashes in a cooler, you don't need a blanket. You only lose maybe 5 degrees in 8-10hrs. you're not going to notice that in the finished product.

Possibly a stupid question, what benefit would you get from mashing for that long?

Offline bigpete225

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Re: overnight HERMS
« Reply #7 on: June 23, 2018, 02:00:56 PM »
I asked the same question a few months ago.  I can't really say for a HERMS, but I mash in a cooler and wanted to get a brew in over a busy weekend so wanted to break it up.  I ended up going a full volume mash (no sparge), wrapped up the cooler in blankets and let it go about 8 hours overnight.  I think I lost something like 5 degrees.  People said I'd get better efficiency, but I don't think that ended up being the case... I get s****y efficiency anyways (a problem I'm working on).  In the end it worked out fine.  Turned out to be a great beer that I served at a party... killed that keg in a couple hours.

Offline soymateofeo

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Re: overnight HERMS
« Reply #8 on: June 29, 2018, 09:20:37 PM »
i ended up mashing for 6 hours in ghe day. started in the morning and finished in the afternoon.  i recirculated full volume and then closed the lid.  the herms coil was drained and put away.  lost 4-5 degrees.  i always get great conversion when I recirc. my efficiency wasn't too great 68% but not a problem. the beer turned out great.  very pleased.

Offline Robert

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Re: overnight HERMS
« Reply #9 on: June 29, 2018, 09:47:36 PM »
i ended up mashing for 6 hours in ghe day. started in the morning and finished in the afternoon.  i recirculated full volume and then closed the lid.  the herms coil was drained and put away.  lost 4-5 degrees.  i always get great conversion when I recirc. my efficiency wasn't too great 68% but not a problem. the beer turned out great.  very pleased.

I'd guarantee after 6 hours you had 100% conversion (15 minutes can do do that.)  The difference in extraction is just lautering efficiency.  Maybe a short recirc at the end before runoff could fix that.
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Offline soymateofeo

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Re: overnight HERMS
« Reply #10 on: July 27, 2018, 06:08:32 AM »
i went no sparge so 68 is pretty good. i neex to really pay attention to wear I leave liquid behind.

Offline goose

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Re: overnight HERMS
« Reply #11 on: July 27, 2018, 01:18:32 PM »
Most of your conversion will occur in the first 10 minutes of the mash, which is why maintaining proper pH in the mash will have a great impact on your extraction efficiency.  I don't think that recirculating overnight will gain you that much more sugar from the grain.  I use a RIMS system here and only mash for an hour or so before running off the wort.  You can also get a good idea of how good your extraction is by measuring your first runnings.  They should be in the range of 50% or so higher than you desired OG.

Another trick I learned when I worked at a brewery is to knife the grain bed.  I do this all the time and have good efficiency in my system.  You only need to go a couple inches into the grain bed when lautering (obviously, don't go too deep because of channeling) and do it in a checkerboard pattern across the grain bed several times during lautering  If I remember correctly, Gordon Strong has mentioned this in his book as well.  I maybe knife a bit more than many, but it works and it is a trick that old German brewers used to increase their extraction.
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Offline Robert

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Re: overnight HERMS
« Reply #12 on: July 27, 2018, 02:33:42 PM »
I have always knifed my grain bed, exactly as Goose mentions.  Then a few days ago, I tried skipping it just to see what happened.  I saw no channeling and no change in lautering efficiency. 

Anecdotal, I admit, and the reason for my result is probably that this is just one tool in your kit.  Other factors I take care in include but are not limited to ensuring good intact husks, controlling pH, having sufficient calcium, doing a mash off; even grist, mash program and lauter tun design are significant.  Use any and all tools available to improve your efficiency.

Just to be safe I'll keep knifing in future.  If you tend to form a lot of top dough, definitely do it.

For a good overview of conversion and lautering efficiency:  http://braukaiser.com/wiki/index.php/Understanding_Efficiency
Rob Stein
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Offline goose

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Re: overnight HERMS
« Reply #13 on: July 27, 2018, 02:47:13 PM »
I have always knifed my grain bed, exactly as Goose mentions.  Then a few days ago, I tried skipping it just to see what happened.  I saw no channeling and no change in lautering efficiency. 

Anecdotal, I admit, and the reason for my result is probably that this is just one tool in your kit.  Other factors I take care in include but are not limited to ensuring good intact husks, controlling pH, having sufficient calcium, doing a mash off; even grist, mash program and lauter tun design are significant.  Use any and all tools available to improve your efficiency.

Just to be safe I'll keep knifing in future.  If you tend to form a lot of top dough, definitely do it.

For a good overview of conversion and lautering efficiency:  http://braukaiser.com/wiki/index.php/Understanding_Efficiency

Another good point Rob!  Doing a mash out will improve lautering efficiency since it will make the wort less viscous and easier to run off into the kettle  Forgot to include this in my last post.
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