Herms Basics and Re Circulation

[taylormade4322]

I recently upgraded my brew system with a HLT containing a herms coil and pump. I have a standard 10 gallon water cooler with a false bottom.

My intention with the upgrade is to increase my overall brewhouse efficiency and gain a more consistent beer.

With that, here are my questions:

I have the re-circulation of the wort pretty much figured out during my initial mash step....(i.e. re-circulate wort on top of grain bed for 50 minutes to 1 hour maintaining target temperature through the coil and HLT water).

My big question is the fly sparge and mashout step using re-circulation. Is it recommended to raise the temperature of the entire mash tun to the desired mashout temp before I begin to fly sparge and collect wort in the kettle? In most cases my recipes call for mashout at 168. Getting the entire tun to 168 will require a temperature infusion to achieve that goal.

Or....do I simply just raise my hot liquor water to the desired mashout of 168 and begin re circulate that over the grain bed and collect in the kettle? This method will obviously take a bit of time for the tun to achieve a complete internal temp of 168.

Not sure if I am over complicating things or not.

Any suggestions would be greatly appreciated.

Cheers

 

[biertourist]

I recently upgraded my brew system with a HLT containing a herms coil and pump. I have a standard 10 gallon water cooler with a false bottom.

My intention with the upgrade is to increase my overall brewhouse efficiency and gain a more consistent beer.

With that, here are my questions:

I have the re-circulation of the wort pretty much figured out during my initial mash step....(i.e. re-circulate wort on top of grain bed for 50 minutes to 1 hour maintaining target temperature through the coil and HLT water).

My big question is the fly sparge and mashout step using re-circulation. Is it recommended to raise the temperature of the entire mash tun to the desired mashout temp before I begin to fly sparge and collect wort in the kettle? In most cases my recipes call for mashout at 168. Getting the entire tun to 168 will require a temperature infusion to achieve that goal.

Or....do I simply just raise my hot liquor water to the desired mashout of 168 and begin re circulate that over the grain bed and collect in the kettle? This method will obviously take a bit of time for the tun to achieve a complete internal temp of 168.

Not sure if I am over complicating things or not.

Any suggestions would be greatly appreciated.

Cheers

You should note that when you recirculation mash you will accelerate the rate of conversion; in my experience the mash is accelerated by about 15 minutes -so if I'd normally expect a recipe to fully convert in 60 minutes I only mash for 45 minutes. You can definitely finish full conversion of a large % 2 row base malt mash in 30 minutes with a recirculated mash, though. -If you're brewing a beer that requires some body -say oatmeal stout, then you definitely want to cut the mash time short if you're recirculating (I just don't recirculate these beers any more).


Other than that note, you're correct. If you want to do a mashout step then raise the temp to your mashout temp BEFORE you start sparging to stop the enzymes from continuing fermentation.

The easier and safer way to fly sparge is to just start adding your HLT water to the MLT while it's still full and keep the liquid level about 1" above the surface of the water -you just try to match the inflow to the outflow with the two ball valves. To maximize efficiency you want the sparging to run REALLY slowly so that it takes about 1 hour from beginning to end. -The rate of flow will change as the sparge continues it will start to run slow at first and then faster.


If you have highly alkaline water you'll want to acid treat your sprage water to avoid extracting tannins towards the end of the sparging and maybe sparge a bit on the lower end of the scale (higher temps and higher ph drives tannin extraction from malt husks).



Adam

 

[taylormade4322]

Adam,

Thanks for taking the time to reply to my post. I appreciate your advice and willingness to share your experiences.

I will for sure consider adjusting the time on the re circulation of the initial mash step. I will also monitor my Mash Ph and SG as I get close to final boil volume. If I have to shut it down and be a little short on wort, so be it.

So I am clear though....There would be no need to add a temperature infusion step, mix up mash to evenly distribute my mash out temp of 168, and then begin to fly sparge with HLT water of 168? I guess it I did that I would be defeating the purpose of setting up a nice grain bed and re circulating my initial mash to achieve a nice clear wort.

I guess I am getting stuck on knowing weather or not the entire tun has to be at the 168 number before I run off into the kettle.

My though was to just bring the HLT up to 168, fly sparge over the bed, and start to drain...eventually the entire tun will be at 168. I am guessing it will take about 10-15 minutes. I am planning a drain rate of about .25-.50 quarts a minute depend on what the grain bed will allow.

I pretty sure I am seeing the light on this but I just wanted to make sure I didn't have any fatal flaws before I invest an afternoon with bad technique.

Thanks

~Darren~

 

[cantrell00]

I have the exact same setup as you & this is what I do...

If I am doing a 60 minute mash, I shut the pump off at 45 minutes & raise the HLT temp to 168... Once the HLT is at 168, I turn the pump back on, raise the MLT to 168. Switch the hose from HERMS out to MLT to HLT drain to MLT & adjust the valves back to a trickle to fly sparge until I am at my boil volume..

My PID sensor is at the MLT inlet from the HERMS so the PID also regulates the temp of HLT water while sparging.

Last batch was ~97% mash efficiency.

What kind of false bottom are you using in your cooler?

 

[taylormade4322]

I have a false bottom in the mash tun. I ran my first batch at about 85% mash efficiency but I did run into a few issues with getting the re circulation rate to be correct.

It seemed that I had a bit too much water on the grain bed and compressed things down a bit. I didn't get a stuck sparge but I know it had to be close to happening.

Next batch (this weekend) I plan on being really cautious on the amount of water over the grains.

As I mentioned though I did hit the numbers pretty well.

I am sure it is going to take a bit of trial and error, as it does with all systems, to get this thing dialed in.

I do like the concept of the circulation through hot liquor water. The mash temp remained right on the nose.

I am thinking this next batch will be with no mash out though. Just start sparging 168 water and draining.

I found it really hard to get that mash temp up to 168-170 through the entire before I began to sparge and drain to the kettle. Maybe a bit higher temp water for a few minutes to kick start it may help?

 

[taylormade4322]

Forgot to add that I have just a standard stainless steel false bottom. Not sue if that is clear or not?

It seems to work really well and never seemed to have a problem with it batch sparging over the past few years.

 

[cantrell00]

I see... I have a domed false bottom that came from adventures in homebrewing....

Rice hulls go a long way towards improving the mash recirculation...

 

[taylormade4322]

Do hulls have any effect on the flavor or gravity of the wort/beer? I have seen this suggestion in other threads.

Also, I am think about increasing the water/grain ratio just a bit. I was running at about 1.25. I may ramp that up to 1.5 on the next batch. Hell, l have the room in the tun...I mind as well.

 

[cantrell00]

Do hulls have any effect on the flavor or gravity of the wort/beer? I have seen this suggestion in other threads.

Also, I am think about increasing the water/grain ratio just a bit. I was running at about 1.25. I may ramp that up to 1.5 on the next batch. Hell, l have the room in the tun...I mind as well.

They only make lautering more efficient. Don't add anything as far as taste, etc. Benign in that regard.

I would try rice hulls and leave the mash ratio alone at first. Relative to style objectives.

8 oz of hulls per 5-6 gallons has fared very well for me.

 

[biertourist]

I would agree with rice hulls to help reduce the risk of a stuck mash / stuck sparge.

You also don't want to run the liquid out full blast when draining the mashtun -that will get you a stuck sparge faster than anything.

You should also try "malt conditioning" to reduce the risk of getting a stuck mash / stuck sparge if you crush your grain at home -just add your malt to a 5/6 gallon bucket and spray hot water over it with a spray bottle - you want 2% water by weight vs. the grist weight -this is about 100ml for an 11lb grist.
-Spray evenly while rotating the bucket to get the water equally distributed over all the malt and then let it rest for 10-20 minutes and crush. You won't believe how beautiful and intact it makes your husks. (I only use rice hulls for the most high risk mashes now.)


Adam

 

[thekraken]

If I am doing a 60 minute mash, I shut the pump off at 45 minutes & raise the HLT temp to 168... Once the HLT is at 168, I turn the pump back on

Just curious why you shut the pump off while raising the HLT to mash out temps? I assume so the recirculation doesn't slow down heating up the HTL? If so, have you timed doing it that way vs mashing out with the pump running?

In regards to the rice hulls, does one need to pre-soak them or make adjustments to their strike volume to account for water absorption? Finally, if you pre-soak the hulls does it really matter if you use your chlorinated tap water to saturate them with?

 

[cantrell00]

Just curious why you shut the pump off while raising the HLT to mash out temps? I assume so the recirculation doesn't slow down heating up the HTL? If so, have you timed doing it that way vs mashing out with the pump running?

In regards to the rice hulls, does one need to pre-soak them or make adjustments to their strike volume to account for water absorption? Finally, if you pre-soak the hulls does it really matter if you use your chlorinated tap water to saturate them with?

It ramps the wort faster if the HLT is already at the temp you are shooting for. I have tried both ways and if you just raise the PID & continue circulating, the ramp time is slower because the element is heating twice the volume of water. In total it is the same amount of time overall but the time it takes for the wort to go from 150-168 is much shorter. And because my MLT is a cooler, I don't have to worry about temperature drift over a short 15 minute period while the wort isn't being recirculated.

I am not certain that I even need to mash out but it creates another excuse to use the PID for something else so I do it anyway. Heh..

I just add the rice hulls in with the grist to the mash water... You want the hulls mixed throughout...

 

[swanwick]

What about

1. Boiling some water in the BK during mash
2. A few mins before mashout, stop re-circ
3. Pump boiling water from BK until HLT is 10deg over mashout
4. Restart re-circ until mashout temp is reached in MLT.
5. If HLT drops to mashout temp before MLT comes up, either have HLT heat come on or pump more boiling water from BK into HLT
6. At mashout temp, if HLT is still above sparge temp, add cold water to HLT
7. Switch to sparging with the newly topped up sparge temp HLT water

This requires 2 pumps and 3 vessels, but if you have em it seems a slightly more efficient way. Any reason not to do this?

 

[milldoggy]

I have a similar herms. I tried a few different approachs. Mash for 60 then raise the hlt to 168 recirc all the time, turning off pump, raising hlt, then recirc. I settled on no mash out, and fly sparging with mash temps. The bed is draining fine, so you do not need the mash out to loosing things. It saves time and when I did mash out, never really noticed much of an efficiently increase. I would suggest you try and find what works with your system, but sometimes the simplest is the best. My eff is around 82-84%

I have also started stirring my mash @30 mins. Not sure it is doing anything. Just want to ensure it is all mixed.

 

[perle]

You should note that when you recirculation mash you will accelerate the rate of conversion; in my experience the mash is accelerated by about 15 minutes -so if I'd normally expect a recipe to fully convert in 60 minutes I only mash for 45 minutes. You can definitely finish full conversion of a large % 2 row base malt mash in 30 minutes with a recirculated mash, though. -If you're brewing a beer that requires some body -say oatmeal stout, then you definitely want to cut the mash time short if you're recirculating (I just don't recirculate these beers any more).
Adam

I'm working on the same problem, and as luck would have it, my first test beer is planned to be an oatmeal stout. I was planning on using Iodine to determine when the mash is finished. What is the issue with recirculating an oatmeal stout? Does it "thicken" the wort too much? Would adding the oatmeal later in the mash solve the problems?

 

[biertourist]

I'm working on the same problem, and as luck would have it, my first test beer is planned to be an oatmeal stout. I was planning on using Iodine to determine when the mash is finished. What is the issue with recirculating an oatmeal stout? Does it "thicken" the wort too much? Would adding the oatmeal later in the mash solve the problems?

Whether or not you get a stuck (recirculation) mash or not depends primarily upon your false bottom % open area, the height to width ratio of your mash tun and how quickly you recirculate. Oatmeal as an ingredient can increase the likelihood of a stuck mash as it does increase the viscosity.

The reason I stopped recirculating beers that I want to have more body in is simply to prevent over-converting. -I mash these high to leave some dextrins, but mash time is also an important variable.

You could certainly and probably should do an iodine test but remember that an iodine test doesn't give you any shades of gray and it doesn't tell you the makeup of your wort sugars, it mostly just tells you whether you have STARCH left or not. -It helps you to say "hey, I just passed the iodine test, I probably shouldn't let the mash continue too much longer as I want to leave some larger sugars behind."


Adam

 

[cantrell00]

Testing @ 15, 30, 45 min with a refrac will tell you a lot about what's going on in the mash.