HERMS Step Mash Question?

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My heat ex mounted in my HLT is only 25 ft but it has been more than adequate for simply maintaining temp... which is all I've asked it to do up until this point.

I have a 50 ft coil I bought to replace it so maybe I'll switch that one in, and do some experimenting.

It would be interesting to see if you could make any material difference on the amount of boiling water you would have to use.

Plus, if i do overshoot in the mash itself, I can pretty easily rectify it by adding cold water to my HLT and circ'ing... I've done that once or twice and that is a very quick and very easy adjustment on my rig... even with the 25 ft coil
 
For my purposes, a simple 2-3 quarts of boiling water and a quick stir before I begin the recirc. just seems too simple.
 
yeah... you're probably right... with that kind of volume required, it is probably not worth the effort.

Especially since you're not going to be doing multiple steps, requiring something like doubling up on volume.
 
Yah my Pils is three steps, one with the initial strike, the other two from 2qt. boiling additions.
 
I'll tell you what I have learned since first playing with the herms design in the early 90's.
You can not use ice chests/coolers for a mash tun on a working herms unit . The cooler is designed to hold its temperature. It will fight with you if you try to step mash. The cooler will absorb the heat first, then allow the liquor temp to rise a bit, then the cooler again will absorb, then again allow the wort to rise. This is a very inefficient way to raise mash temps. That's why cooler brewers do single infusion mashing and will tell you don't worry about reaching mashout temps while sparging.

Boiling water additions kill off important enzymes, and it also changes your mash thickness, which in turn changes your worts profile. When you use a RMS RIMS or HERMS type setup, your water/grain ratio stays the same. Thicker mashes will protect your enzymes as you boost the temps when step mashing.

You can actual tweak your wort profile from multi rests utilizing the beta and alpha amalyase conversions at different time intervals.
As you know, a single infusion at 152-3* is a compromise between the two working temps of those enzymes.

When using a heat exchange coil in the hlt, there are two things to consider. One is to use a large enough coil to be able to have an increase of 2* per minute minimum.

50' of 1/2"od/3/8"ID copper coil is used by many brewers using a three keg herms setup.

Better yet is to get a hold of 5/8"od/1/2"id convoluted copper coil for the exchanger. I think B3 now sells it by 25' lengths. To allow for maximum thermal transfer, an electric stir paddle should be placed in the hlt.

The second is how to control the temperature using the herms.

I have found the easiest/cheapest way is to add a bypass loop into the plumbing at the hlt, and add a thermometer inline after the coil/loop plumbing returning to the mashtun.

The loop allows you to adjust how much wort flows through the coil, or allows a complete bypass of the coil when desired temperatures are reached. This allows you to run the hlt water temperature much higher then the mash bed temps. The valves on the loop can be two ball valves, or one three port diverter valve. This way you can keep your pump running keeping the grainbed temp even.

A full false bottom (sabco offers one style) is really the best for the recirculation system without compacting the bed or getting stuck sparges.

To beef up the system even more, what you can do is go with a burner under the mashtun like a RMS (recirculating mash system) uses. Not only do you have the herms coil stepping up your temps, but you can also apply direct heat to the tun to boost the degrees per minute while stepping to the next rest.
 
Are you able to control the wort temperature returning to the mash as the mash warms up, or does the wort temp go over the desired rest temperature at the end of the step.
 
OLDBREW said:
Boiling water additions kill off important enzymes, and it also changes your mash thickness, which in turn changes your worts profile. When you use a RMS RIMS or HERMS type setup, your water/grain ratio stays the same. Thicker mashes will protect your enzymes as you boost the temps when step mashing.
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All available evidence (except perhaps your own anecdotal evidence) suggests otherwise.

Fix wrote about extensive experiments in mashing programs whereby he would step from a beta glucan rest to a 60 celcius then 70 celcius rest, mostly with boiling water infusion (some direct firing in the first step).

Not only was his mash enzymatically healthy, but he got extremely fast conversion and attributed this to the lower rest. Any degradation in enzymatic activity was so small that it could not be observed in the presence of the positive impact on enzymes given by the lower rest.

Of course, he didn't use a protein rest with malts have a kolbach index of 40 or more, so you probably think he was a flaming idiot.

My own step mashing with boiling water infusions show no observable negative impact on enzymatic activity.

This is intuitive as we know from the brewing literature that enzymes are not denatured by brief exposure to near boiling temperatures. Intuitively we would expect repeatedly heating the wort to high temperatures through a HERMS coil to be more damaging to enzymes than an exposure to high temperatures for a small number of seconds while stirring is taking place. It's likely that neither practice is particularly destructive of enzymes but it is surprising that you would defend stepping through a HERMS coil is somehow exposing the wort to a lower thermal load than stepping via hot water infusion. The thermal load is certainly higher in the HERMS case, do to heat losses in the plumbing. Even if we assume a theoretical zero loss HERMS, the thermal loading would be by definition the same. Somewhat higher absolute temperature exposure (to part of the mash) in the hot water case and somewhat higher time exposure in the HERMS case.

Mash thickness, so long as it is reasonable (1 qt per lb to 2 qt per lb and BIAB experience suggests higher) has minimal impact on wort composition. Again, certainly dwarfed by other factors.
 
Sawdustguy said:
black dog1.jpg
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Very beautiful rig! Make's my old rig curl up and hide..:)
 
I am not sceeeered of using mashing in at 1.5qt/lb and ending up at 2.0qt/lb (my usual mash thickness) to accomodate two separate mash steps.

I have not been around long, but I have seen boiling water additions used to step mash, and the water is only boiling for an instant as the mash cools it almost immediately. Never heard of or seen an issue with conversion.

I am not scared... the enzyme boogeyman isnt a big deal.

You can watch my brewcast on the 27th and watch me murder my enzymes!

You know, you cannot make good beer unless you chill the wort quickly either, it was written, in the 80's. GAHHH
 
Sudbuster said:
Gotcha........ Is the OP still around?? I agree with POL. I've tried steps with RIMS, HERMS, and Steam. For me, boiling water infusions achieve the best efficiency and best wort profile.
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You agree with me? No one agrees with me... can we be friends? :D
 
remilard said:
With science on one side and enthusiasm on the other?

Thats what the internet is for.
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…And you have to believe everything you read on the internet.

I would also like to point out that for those that think that adding a little bit of boiling water/wort to your mash will irreversibly denature your enzymes, think about how long that water/wort is actually at that temp once added to the mash. The temp will be dramatically lowered by the mash before any damage could occur and even IF some of your enzymes were denatured, there would still be sufficient amounts to complete your mash goals.

On another note, for those in the infusion=death camp, how I hope you don’t think steam is any better. The amount of localized heat (steam carries a lot more heat than boiling water, 540 cal/g) would be far more likely to denature than boiling water. For the record, I don’t think that the amount of heat needed to lose all enzymatic activity could ever be applied to a mash and still have a mash that is within brewing temps. Maybe if you tried to go up to 90C but then you’d have a nasty brew anyway.

I guess the moral of the story is that brewing is like religion and bbq, everybody has their own way of doing it and are convinced that theirs is the right way.
 
remilard said:
All available evidence (except perhaps your own anecdotal evidence) suggests otherwise.

Fix wrote abo
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Actually, I believe he is correct. I have been reading extensively about decoction brewing lately and it appears that the mash still converts because of rests at the appropriate temperature before the boil denatures the enzymes. Of course, the enzymes in the non-decocted portion continue to work on the mash.

Here is an interesting research article of enzymes and while not brewing specific I believe it holds water:

http://www.associatedcontent.com/article/8679/the_effect_of_temperature_on_amylase.html
 
JVD_X said:
Actually, I believe he is correct. I have been reading extensively about decoction brewing lately and it appears that the mash still converts because of rests at the appropriate temperature before the boil denatures the enzymes. Of course, the enzymes in the non-decocted portion continue to work on the mash.

Here is an interesting research article of enzymes and while not brewing specific I believe it holds water:

http://www.associatedcontent.com/article/8679/the_effect_of_temperature_on_amylase.html
Click to expand...

Boiling a portion of the mash for many minutes is sure a different level of thermal loading than mixing 210 degree water and 140 degree mash to make a 150 degree mash in less than a minute, isn't it?

I will concede that boiling enzymes hard for half an hour will effectively denature them.

Lets get back to the unrelated issue of infusion mashing.
 
remilard said:
Boiling a portion of the mash for many minutes is sure a different level of thermal loading than mixing 210 degree water and 140 degree mash to make a 150 degree mash in less than a minute, isn't it?

I will concede that boiling enzymes hard for half an hour will effectively denature them.

Lets get back to the unrelated issue of infusion mashing.
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Since most of us have effectively done steps using infusions of boiling water it sure can be done but I bet it's the same principle anyway. Probably some of the hot infusion denatures the enzymes located at the point of contact but most of them rest at the desired temp.

I guess my question is "how quickly enzymes denature at a particular temp"? Is it immediate? Is it 1 minute? 5 Minutes?
 
JVD_X said:
Since most of us have effectively done steps using infusions of boiling water it sure can be done but I bet it's the same principle anyway. Probably some of the hot infusion denatures the enzymes located at the point of contact but most of them rest at the desired temp.

I guess my question is "how quickly enzymes denature at a particular temp"? Is it immediate? Is it 1 minute? 5 Minutes?
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The thing that we must understand about denaturation is that it is not always irreversible. There is a point (time/temp) that if you go beyond, the damage is done and cannot be undone. That being said, if you heat enzymes up and then cool them back down (within limits), their can activity return. The problem with the study previously posted is that they say there is no activity at 80C but do not address activity once cooled. (That any there is a big jump fro 37 to 80 with no points in between.)

In post 41 I previously mentioned an article where Alpha Amylase was incubated for 15 minutes at 90C and 50% of the enzymatic activity still remained after being cooled. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1133484/pdf/biochemj00196-0049.pdf

This illustrates my point that while there may be no activity at a higher temp, the enzymes are not necessarily destroyed. This is why infusion/RIMS/HERMS works. You can overheat but if not too hot or for too long you are ok.
 
OLDBREW said:
I'll tell you what I have learned since first playing with the herms design in the early 90's.
You can not use ice chests/coolers for a mash tun on a working herms unit . The cooler is designed to hold its temperature. It will fight with you if you try to step mash. The cooler will absorb the heat first, then allow the liquor temp to rise a bit, then the cooler again will absorb, then again allow the wort to rise. This is a very inefficient way to raise mash temps. That's why cooler brewers do single infusion mashing and will tell you don't worry about reaching mashout temps while sparging.
Click to expand...


This statement is absolutely false. The cooler isn't absorbing any significant amount of heat, by their very nature, insulative materials have low specific heat. The cooler is preventing the mash from losing heat, not the other way around. Using an uninsulated vessel is far worse if you're looking for fast steps.

In a HERMS, the name of the game is effectively transferring electrical energy to your mash. The heating element does an efficient job of transferring electrical energy to thermal energy in the HLT, then the brewer needs to transfer the thermal energy to the mash. Every BTU of energy that's lost to the environment reduces your maximum potential step speed. Ideally every portion of your system should be insulated, vessels, lines, valves, et al. If you do it right, it's likely the bottleneck in your efficiency is how fast you are able to recirculate your wort. If you have a fairly powerful pump and a good false bottom/manifold design (theoretically) you can keep upping your pump speed until the energy transfer is maxing out the HLT element power.

Using numbers from ProMash, 20 lbs of grain mashed in at 1.25 qts/lb (roughly a 1.050 beer) requires 61.3 kJ to raise the mash 1°F. To go from 130 to 152 requires 22 x 61.3 = 1,350 kJ. A 2,000W heating element is adding about 2 kJ per second to your HLT, or 120 kJ/minute. For a 100% efficient system (i.e. ZERO heat loss), you would expect to be able raise the temp of the mash from 130 to 152 in (1,350/120=) 11.25 minutes. That's a 2°F rise per minute. If you had a 5500W element, your theoretical temp rise limit is ~5.4°F/minute.

Back to the original point. None of this is achievable without very good insulation throughout the system.
 
remilard said:
You said:



Well I have bought plenty of grain from Belgium and Germany and read the analysis*. The vast majority of it has a kolbach index above 40.

Now when I see a kolbach index in the low 40s, as I nearly always do with German and Belgian grain, I decide not to employ a protein rest.

You obviously think I am wrong. Let's hear why.

*Er, what I meant to say is that I remember with John Maier and George Fix were just starting to buy their malt from Germany and Belgium.
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kolbach of over 45 is considered over modified 40 can improve from a short protein rest this last batch my kolbach was 37 and 79 fine grind extraction with a difference of fine/coarse @ 1.7, and friability was 81, would this benefit from a protein rest?
 
This statement is absolutely false. The cooler isn't absorbing any significant amount of heat, by their very nature, insulative materials have low specific heat. The cooler is preventing the mash from losing heat, not the other way around. Using an uninsulated vessel is far worse if you're looking for fast steps.
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well if a cooler doesn't absorb the heat, why do you have to preheat a cooler, or put water 15-20* higher then strike temps in the cooler?
 
remilard said:
Somehow that will kill enzymes, despite the fact that they were never alive.
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By using the word kill with enzymes it is technically "denature", and once you kill the beta amalysis it does not come back when you lower the temperature
as someone tried to write.
 
OLDBREW said:
kolbach of over 45 is considered over modified 40 can improve from a short protein rest this last batch my kolbach was 37 and 79 fine grind extraction with a difference of fine/coarse @ 1.7, and friability was 81, would this benefit from a protein rest?
Click to expand...

That doesn't mean that other people are wrong for not doing a protein rest with the malt they have.

It looks like you are uninterested in defending all the crap you were talking the other day, I'm not really interested in helping you to weasel out of it by acting like you were just talking about the malt you happen to be using.
 
Interesting question about preheating insulated cooler, the thermal mass of the grain bill over 10 times the mass of the cooler liner. Any of the Herms systems able to raise fluid temperature from 130-152 at 1 gpm flow and maintain 152 discharge temperature during step ?.
 
the reason they still use decoction mashing is because of a mystery known as the maillard reaction. Science still is just learning about this, and it appears the decoction process brings out the proper enzymes for melanoidian formation, and the decocted boils induces the maillard reaction in each step up. Bocks, lager, wheats all benefit from decoction mashing. The problem is it is time consuming and the cost to produce makes the industries accept lower quality to stay afloat and go to quanity and cost efficiency.
 
remilard said:
That doesn't mean that other people are wrong for not doing a protein rest with the malt they have.

It looks like you are uninterested in defending all the crap you were talking the other day, I'm not really interested in helping you to weasel out of it by acting like you were just talking about the malt you happen to be using.
Click to expand...

What I am saying that since this cooler way of brewing has taken off, the Main focus is on single infusion mashes, making it easier for the average Joe to make beer. Okay, this is a good thing because it keeps the brew shops and the industry running, but there is a lot of information going around like "a protein rest is not needed because the grain is highly modified". Hmmm.. how do you know what the grain is unless you look at the analysis report that is readily available. So the answer should be.. look at the malt analysis report or ask for a copy when buying your grains, and then determine is a protein rest beneficial.
I still use unmalted wheats, corn grits, oats, and rice in brewing. I still step mash or decoction mash on certain brews I do. I determine what I want out of the grist and can tweak the outcome of my wort during the mashing process. Some of this information comes from the malting analysis reports. no two maltings are alike.

I have tried herms step mashing with a cooler and the cooler does fight the process.
 
OLDBREW said:
well if a cooler doesn't absorb the heat, why do you have to preheat a cooler, or put water 15-20* higher then strike temps in the cooler?
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It does absorb heat, everything does. It also does the best job of preventing the mash from losing heat.


Also, I think you have a different cooler than me, because mine needs less than 5°F to preheat.
 
JKoravos said:
It does absorb heat, everything does. It also does the best job of preventing the mash from losing heat.


Also, I think you have a different cooler than me, because mine needs less than 5°F to preheat.
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the design of a cooler is to hold temperatures.
when I have tried to raise temps, it seems the cooler will absorb the heat first then the temperature will raise. I used both Igloo and Coleman coolers trying it.
 
kladue said:
Are you able to control the wort temperature returning to the mash as the mash warms up, or does the wort temp go over the desired rest temperature at the end of the step.
Click to expand...

when I get about 4* of the target temp I use the bypass loop diverter valve so im recirculating the mash liquor. The mash bed will climb a couple of degrees and I can adjust the loops valve to allow more heat if needed. I don't have to turn the pump off which allows the uniformity of temperatures throughout the entire bed.
when maintaining temps using 50' of 1/2" refrigeration copper, the difference between the hlt water temp and the mash temp would be about 9 -11 degrees. Using the convoluted copper it is 2 degrees difference.
 
OLDBREW said:
the design of a cooler is to hold temperatures.
when I have tried to raise temps, it seems the cooler will absorb the heat first then the temperature will raise. I used both Igloo and Coleman coolers trying it.
Click to expand...


The cooler and mash will absorb heat simultaneously. Anything else defies the laws of physics.
 

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