HERMS, RIMS, Step, Decoction. A statement, question and/or opinion

[SW Ohio Keith]

A brief background. I've been brewing AG for a couple years 5G batches on propane, and like many of you, I'm a professional tinkerer. I've brewed 65G so far this year, and I'm almost finished with a new 1/2 bbl eHERMS brewery and as of late I've been laid up with a back injury, so needless to say, I've been spending a lot of time reading here. Last night I read some "Herms vs Rims" debates, and that sent me down another rabbit hole. One comment kept coming up that RIMS was like a sports car and HERMS is like a school bus in terms of temp control, specifically during step mashes. So, I got to thinking, am I missing something on this step mashing thing?

After some more wandering around the rabbit hole, the conclusion I have come to is that with modified grains, step mashing is not very useful. Am I missing something? Same for decoction mashing. It seems this is an old practice that has since been solved by the maltier and the industrial revolution.

Mashout.

Some argue mashout is to stop the enzymatic process, some say to thin the mash for a better sparge. Seems to me, since the Alpha and Beta amalayse do the conversion, once the conversion is complete, it's done and the 5-10 min it takes to get my wort in the BK and boiling kind of negates the need to 'denature the enzymes' in my MT. I haven't calculated my brewhouse efficiencies in a couple years, but my pre-boil gravity is spot on or over weather I mash out at 170 or less, and the final sparge runoff is typically mid to low 5 pH and 1.010-1.020 gravity. Again, am I missing something.


I don't know what I don't know. Thoughts, feedback, opinions...

Keith

 

[TheMadKing]

A brief background. I've been brewing AG for a couple years 5G batches on propane, and like many of you, I'm a professional tinkerer. I've brewed 65G so far this year, and I'm almost finished with a new 1/2 bbl eHERMS brewery and as of late I've been laid up with a back injury, so needless to say, I've been spending a lot of time reading here. Last night I read some "Herms vs Rims" debates, and that sent me down another rabbit hole. One comment kept coming up that RIMS was like a sports car and HERMS is like a school bus in terms of temp control, specifically during step mashes. So, I got to thinking, am I missing something on this step mashing thing?

After some more wandering around the rabbit hole, the conclusion I have come to is that with modified grains, step mashing is not very useful. Am I missing something? Same for decoction mashing. It seems this is an old practice that has since been solved by the maltier and the industrial revolution.

Mashout.

Some argue mashout is to stop the enzymatic process, some say to thin the mash for a better sparge. Seems to me, since the Alpha and Beta amalayse do the conversion, once the conversion is complete, it's done and the 5-10 min it takes to get my wort in the BK and boiling kind of negates the need to 'denature the enzymes' in my MT. I haven't calculated my brewhouse efficiencies in a couple years, but my pre-boil gravity is spot on or over weather I mash out at 170 or less, and the final sparge runoff is typically mid to low 5 pH and 1.010-1.020 gravity. Again, am I missing something.


I don't know what I don't know. Thoughts, feedback, opinions...

Keith

Just an opinion from me

step mashing is a very useful process if you really want to control your beer characteristics. You can perform a ferulic acid rest to help control your mash pH, you can target alpha and beta activity more specifically, and in my experience I've ended up with a much more fermentable wort doing step mashing. I've also ended up with beers that seem to drop clear on their own a little faster too.

I use step mashing exclusively for German lagers where you want that "malty but attenuated" character and a nice dry finish. My Helles finished out at 1.006 and my Helles Bock finished out at 1.011 which I attribute to the step mash since that's really the only thing I did differently. In the past I've had similar beers finish at 1.010 and 1.020 respectively.

I also don't agree that RIMS is the natural successor to HERMs in terms of technology. They do the exact same thing just slightly differently. RIMS is a little more energy efficient but so what? I'm not going for a minimal carbon footprint with my brew system

I have a HERMs and I can change my mash temp, maintain it, and even cool it using my HERMS coil, and I can do any of those almost as quickly as a RIMS system and I have no risk of scorched wort.

 

[Smellyglove]

I don't get the Herms schoolbus / RIMS sports car thing. As long as you get the coil/tube exit temperature where it should be there's no difference. But if you use the HLT as HERMS as I see many Americans do, I can see the schoolbus vs sports car analogy. I use a compact herms myself 1.8L, and ramp times are way quicker than using a HLT for ramps. When using HLT you need to heat both wort and HLT water at the same time. I only heat wort + 1.8L. I've tried a coil in my HLT (years ago) and did it just once (and a few tests), it's inferior if you only have that much wattage to spend when it comes to ramp-times comparing to a compact HERMS.

Step mashing can be nice for some styles. Mashout is great, higher yield (although with a different sugar composition than without mashout), lower viscosity (I can't even look at dirty wort, so I pump to kettle slowly), and halting enzymes.

 

[McKnuckle]

I will render an opinion on the step mashing part.

First, highly modified grains obviate performing a protein rest. The modification aspect is not related to the subsequent saccharification rests that activate amylase enzymes to break down starch into maltose and dextrines.

There are certain types of enzyme behavior that are only practical with a step mash; for example, the classic German Hochkurz mash which utilizes a long rest in the lower part of the range, followed by a shorter rest at the high end prior to mashout.

The purpose of that type of mash program is to create a good amount of fermentable sugars with a long beta rest, but then to liberate a remaining portion of longer chain unfermentables at the high end.

Does this matter? Depends. Try it and see if it makes a difference for you. Personally I think it's nice to do for lagers and is traditional. It's certainly not necessary, just another tool in the box.

 

[applescrap]

Probably what you dont want to hear and many confirmation biased opinions will disagree with me but I remain almost certain none of these factors matter. Literally they dont matter, step, decoction vs single infusion and herms, rim's, vs passive. No matter the whole way round. But if you love brewing then doing decocotion and step mashes will give you joy by extending the day. Just my 2c. I wont respond so need to disagree with me, those that do. This isnt the place for that.

 

[SW Ohio Keith]

I use step mashing exclusively for German lagers where you want that "malty but attenuated" character and a nice dry finish. My Helles finished out at 1.006 and my Helles Bock finished out at 1.011 which I attribute to the step mash since that's really the only thing I did differently. In the past I've had similar beers finish at 1.010 and 1.020 respectively.

I was under the impression that malty and dry were kind of opposites. Is there a beer I could buy that tastes malty and dry? This might be what I'm missing. I like both malty and dry porters but I can't say I've had one that was both. I typically mash my porters higher for the malty, and my lighter ales lower for the crisp dry. Hmmm...

Ferulic acid rest. interesting. I will say that my lighter beers benefited when I would get my TA below about 150ppm (pre boiling my hard water, blend 50/50 w/ RO and adjusting the pH to about 6 before mashing in) Could one skimp on water treatment by doing this rest?

More rabbit hole running, but I appreciate the direction.

FWIW, I didn't come to the conclusion that there was a better HERMS or RIMS, it just seemed that people touted RIMS as better for step mashing (speed) and I just haven't been able to find much justification on step mashing yet. I contemplated HERMS because I had more of the stuff laying around and I felt like I could get better consistency (than single infusion or dump, stir, and wait) and less cleaning (RIMS. although TC wouldn't seem too bad). It was really a toss up though.

Keith

 

[TheMadKing]

I was under the impression that malty and dry were kind of opposites. Is there a beer I could buy that tastes malty and dry? This might be what I'm missing. I like both malty and dry porters but I can't say I've had one that was both. I typically mash my porters higher for the malty, and my lighter ales lower for the crisp dry. Hmmm...

Ferulic acid rest. interesting. I will say that my lighter beers benefited when I would get my TA below about 150ppm (pre boiling my hard water, blend 50/50 w/ RO and adjusting the pH to about 6 before mashing in) Could one skimp on water treatment by doing this rest?

More rabbit hole running, but I appreciate the direction.

FWIW, I didn't come to the conclusion that there was a better HERMS or RIMS, it just seemed that people touted RIMS as better for step mashing (speed) and I just haven't been able to find much justification on step mashing yet. I contemplated HERMS because I had more of the stuff laying around and I felt like I could get better consistency (than single infusion or dump, stir, and wait) and less cleaning (RIMS. although TC wouldn't seem too bad). It was really a toss up though.

Keith

Devils Backbone Helles Bock, Hofbrau Original, Spaten Oktoberfest - the term malty just means the flavors provided by the malt (biscuit, toast, bread, honey), not necessarily sweetness. You can get a ton of malt flavor while still having a very dry beer.

 

[Smellyglove]

It's way easier to just use some form of acid, than mashing for an extended time (2hrs to notice a "big drop"?) at the acid rest temperature, and have to ramp up through the entire temperature spectre, also protein range, just to get the pH right.

But I would never brew a hefeweizen again without a step mash regime.

 

[SW Ohio Keith]

Probably what you dont want to hear and many confirmation biased opinions will disagree with me but I remain almost certain none of these factors matter. Literally they dont matter, step, decoction vs single infusion and herms, rim's, vs passive. No matter the whole way round. But if you love brewing then doing decocotion and step mashes will give you joy by extending the day. Just my 2c. I wont respond so need to disagree with me, those that do. This isnt the place for that.

Man, I'm kind of there with you, I'm just wondering if there is something I'm missing. I'm going herms mostly for consistency, and stepping up batch size. I enjoy brewing, sharing, and drinking, and I think I make really good beer, but, that self doubt comes along and says, you could probably make better beer. Then I drink some more!!!! Occams Razor and curiosity, the malty dry beer!!

 

[SW Ohio Keith]

Devils Backbone Helles Bock, Hofbrau Original, Spaten Oktoberfest - the term malty just means the flavors provided by the malt (biscuit, toast, bread, honey), not necessarily sweetness. You can get a ton of malt flavor while still having a very dry beer.

Awesome. I will try some of these. I guess I always associated malty with sweet.

Smellyglove, what is your steps for a Heffe?

 

[TheMadKing]

Man, I'm kind of there with you, I'm just wondering if there is something I'm missing. I'm going herms mostly for consistency, and stepping up batch size. I enjoy brewing, sharing, and drinking, and I think I make really good beer, but, that self doubt comes along and says, you could probably make better beer. Then I drink some more!!!! Occams Razor and curiosity, the malty dry beer!!

It really depends on how detail oriented you want to be.

You can make really good beer and ignore all of those things, absolutely. But if you really learn the ins and outs of exactly what you're doing during a step mash and the science behind it and why it works, you can add a tool that can improve your beers. If you're not looking for the small nuanced differences a step mash can make, or if you have bigger issues with your process or recipe, it absolutely won't matter. There is 100% undisputed and well understood science behind WHAT it does, and it's just a matter of personal preference whether it improves your beer.

You can always make your beers better unless you get 50 point score sheets back from every competition you enter.

 

[SW Ohio Keith]

Well, I’ll get a couple batches through the new system and then I back to back a recipe and see if I can notice the differences. Part of the new brewery and the consistency thing, being able to discern small recipe differences and being sure it’s not the process.

Opinion on a style to try both ways? I like most all beer

 

[Smellyglove]

Awesome. I will try some of these. I guess I always associated malty with sweet.

Smellyglove, what is your steps for a Heffe?

Depends on which mood I'm in. If I want to make an ester bomb I do a Smelly-verfahren. Basically a Hermann-verfahren but I start at saccharification. If I'm making a "plain" hefe I do 43C, ramp to 63C, ramp to 72C, ramp to mashout.

 

[eric19312]

I find I get higher efficiency and fermentability using a Hochkurz mash. Every once in a while I will look to shorten my brew day and will do a single infusion mash but will take these adjustments into account. Into account means I won't brew a high gravity beer or something that I hoping for high attenuation.

Sometimes I skip actually resting at the higher step and just assume the temperature ramp from 145-148 will spend enough time in the 155-165 range to accomplish the high temp sacc step. From 145 to mash out is usually about 30 minutes on my system (direct fire RIMS).

 

[augiedoggy]

I don't get the Herms schoolbus / RIMS sports car thing. As long as you get the coil/tube exit temperature where it should be there's no difference. But if you use the HLT as HERMS as I see many Americans do, I can see the schoolbus vs sports car analogy. I use a compact herms myself 1.8L, and ramp times are way quicker than using a HLT for ramps. When using HLT you need to heat both wort and HLT water at the same time. I only heat wort + 1.8L. I've tried a coil in my HLT (years ago) and did it just once (and a few tests), it's inferior if you only have that much wattage to spend when it comes to ramp-times comparing to a compact HERMS.

Step mashing can be nice for some styles. Mashout is great, higher yield (although with a different sugar composition than without mashout), lower viscosity (I can't even look at dirty wort, so I pump to kettle slowly), and halting enzymes.

The difference is one is slower and safer, herms is more foolproof but also limited in performance in regards to speed. rims works faster and has better "performance" in regards to being able to both increase and decrease temps quickly. its faster than indirectly heating another medium of liquid to heat yet another body of liquid regardless.
The catch is the rims has to be built, setup and used correctly and is more sensitive to things like flow speed and watt density and if the conditions are not correct the possibility of scorching is possible whereas its not in a herms.

 

[augiedoggy]

It really depends on how detail oriented you want to be.

You can make really good beer and ignore all of those things, absolutely. But if you really learn the ins and outs of exactly what you're doing during a step mash and the science behind it and why it works, you can add a tool that can improve your beers. If you're not looking for the small nuanced differences a step mash can make, or if you have bigger issues with your process or recipe, it absolutely won't matter. There is 100% undisputed and well understood science behind WHAT it does, and it's just a matter of personal preference whether it improves your beer.

You can always make your beers better unless you get 50 point score sheets back from every competition you enter.

Ill also throw out that with the added control over the process you can make your beers more CONSISTENTLY and therefore be able to have better control over tweaking your beer from the point of being ok to great.
also things like decoction mashing absolutely have an effect over things like flavor.

 

[Smellyglove]

The difference is one is slower and safer, herms is more foolproof but also limited in performance in regards to speed. rims works faster and has better "performance" in regards to being able to both increase and decrease temps quickly. its faster than indirectly heating another medium of liquid to heat yet another body of liquid regardless.
The catch is the rims has to be built, setup and used correctly and is more sensitive to things like flow speed and watt density and if the conditions are not correct the possibility of scorching is possible whereas its not in a herms.

Decrease of temps was a good point.

 

[BrunDog]

It really depends on how detail oriented you want to be.

You can make really good beer and ignore all of those things, absolutely. But if you really learn the ins and outs of exactly what you're doing during a step mash and the science behind it and why it works, you can add a tool that can improve your beers. If you're not looking for the small nuanced differences a step mash can make, or if you have bigger issues with your process or recipe, it absolutely won't matter. There is 100% undisputed and well understood science behind WHAT it does, and it's just a matter of personal preference whether it improves your beer.

You can always make your beers better unless you get 50 point score sheets back from every competition you enter.

Totally agree here. You should make good beer, or more importantly, beer that you love, using the technique that works for you. But until you have done complete research on brewing science (and there is much more than you would believe), I don’t think any of us should discredit advanced techniques which are referenced above. Saying “my rig and process make great beer so anything more is a waste” is not a balanced look.

 

[brewbama]

I habitually step mash. It adds ~30 minutes to my brewday due to the time it takes my RIMS to transition from one step to the next. I step mash because that’s the way I like to brew. I like the beer produced with my processes.

Many roads to Rome. To each his own.

 

[mongoose33]

Man, I'm kind of there with you, I'm just wondering if there is something I'm missing. I'm going herms mostly for consistency, and stepping up batch size. I enjoy brewing, sharing, and drinking, and I think I make really good beer, but, that self doubt comes along and says, you could probably make better beer. Then I drink some more!!!! Occams Razor and curiosity, the malty dry beer!!

Remember one thing: just because one person doesn't perceive a difference doesn't mean he's right about there BEING no difference. Different people perceive different things differently. Some hop flavors, for instance, are not perceivable by some people. Same with oxidation, some don't really perceive it.

So when you see someone say "I did that and it made no difference," well, maybe. Maybe they just couldn't tell.

****

I do RIMS, and just did a Kolsch where I did a 10-minute rest at 132, then ramped it up to 149 over the next 15 minutes. That's one thing a RIMS can do--it can move temps faster, which is probably where the sports-car analogy comes from. Anyway, that beer is wonderfully flavorful and yet finishing dry. I don't know how much of that is process and how much would have happened anyway. Next time, I'll probably try just 149.

But one thing I'm trying to figure out: when you underlet (which is what I do) using pretty hot water, say at 162 or so, there has to be some enzyme degradation going on until the mash cools. I keep pumping 162 water to the bottom of the mash tun, which at some point has to warm the grist on the bottom to pretty close to 162. That can't be good for the enzymes.

When I bring up my mash temps from below, rather than dropping them from above, I'm not degrading any enzymes. I had very good conversion with the Kolsch, and excellent flavors. I'm considering always ramping up instead of starting high, just to allow the enzymes the opportunity to do their thing before being denatured.

I suspect @applescrap isn't considering anything like that because, to him, none of this makes any difference at all.

 

[beernutz]

You can read all you want but imo you won't be convinced until you compare the results of the same beer made using different methods. I wasn't at least.

Based on many brewing trials (and some errors) I now only use a Hochkurz step mash schedule when I'm brewing a German lager.. Those beers will almost inevitably be made with Weyerman pilsner grain and I can tell the difference in those type beers when made using a single infusion mash vs with a Hochkurz.

As I believe the Hochkurz procedure makes a positive, perceptible difference in the resulting beer it is worth the extra effort which isn't a lot. YMMV!

I use a natural gas 3 vessel herms system fwiw so take my ramblings with a salt grain.

 

[applescrap]

Not in this case, these are prudent and quality thoughts from a great mind. Yes, if you are under letting the mash over a period of time at 162 then it is reasonable and prudent to think that some conversion could be happening in temp ranges you dont want. I know rm-mn and others have seen conversion in 15 minutes and at that temp, iirc, is possible. While I remain all but certain you wont perceive a difference in taste day in and day out, especially while nashing on a taco, that's not the whole story. The abv and gravities could be substantially affected. That said I think your answer sounds perfect.

If you would like to mash near 149 where I like to mash for fermentability reasons, not taste, then ramping slowly seems perfect. In this case and with lodo practices, I could gladly reccomend a rim or herm system, wonder if a simple ebiab no recirc like mine could do the same. Haha, I asked Marshall to test and he did a ramping mash. I think he was already on it before me. I actually started a thread about it where I got hammered for the idea.

Makes me wonder if some of the great beer you have made with your processes was actually at a higher mash temp than you thought?

 

[augiedoggy]

Not in this case, these are prudent and quality thoughts from a great mind. Yes, if you are under letting the mash over a period of time at 162 then it is reasonable and prudent to think that some conversion could be happening in temp ranges you dont want. I know rm-mn and others have seen conversion in 15 minutes and at that temp, iirc, is possible. While I remain all but certain you wont perceive a difference in taste day in and day out, especially while nashing on a taco, that's not the whole story. The abv and gravities could be substantially affected. That said I think your answer sounds perfect.

If you would like to mash near 149 where I like to mash for fermentability reasons, not taste, then ramping slowly seems perfect. In this case and with lodo practices, I could gladly reccomend a rim or herm system, wonder if a simple ebiab no recirc like mine could do the same. Haha, I asked Marshall to test and he did a ramping mash. I think he was already on it before me. I actually started a thread about it where I got hammered for the idea.

Makes me wonder if some of the great beer you have made with your processes was actually at a higher mash temp than you thought?

underletting a 10gallon mash at 162 could likely result in a mash that like 149 on the top and 158 at the bottom... but as soon as its mixed or recirculated its evened out.. all this at this size should be done long before 15 mins where I agree conversion has already started to take place.

 

[augiedoggy]

BTW As some of you may know I own a small brewpub now and when we made out first beer we messed up and undeletted the mash as well as had a stucK sparge from milling too tight... we mixed the mash manually and messed with it for a while eventually getting some flow for the rims. the results were a mash that started at 136 for a while and slowly climbed to 152 over a period of 2.5 hrs... The beer came out super dry and thin like champane and finished at 1.001! Mainly because the conversion was done before we got the temps over 148.
People loved it but it wasnt at all the same beer we've made with the correct mash schedule since... We called it OOPs blonde ale and actually described what happened on the beer list.