LoDo Techniques

[Yooper]

We need a place for LoDo experts and beginners to share rationale, techniques, and results. This forum is a dedicated place to discuss this specialty part of brewing.

Ask questions, talk about your set up, make suggestions and give advice here!

 

[brewbama]

Dilly Dilly!

 

[MSK_Chess]

yay!

 

[Big Monk]

I’m not sure how to approach this sticky. I think I’ll talk with DieB and see if we can come up with a synopsis post to lead this off.

 

[MaxStout]

I wouldn't mind seeing some kind of list of steps that incorporate LODO procedures, all the way, grain crush to packaging. Point out how each is different from the conventional method. Of course, different people have different ways to brew, and different equipment, but it would be helpful for brewers to go through and try to adopt as many steps as practicable.

 

[Big Monk]

This topic has now been floating around for nearly two years in various forms and under various levels of debate/fervor. Why don’t we take a step back and talk about the fundamentals. Maybe by breaking it back down to the essential topics, theories, and assumptions, we can get at the heart of it in a way that satisfies the already initiated and tickles the curiosity of the newcomer/“on the fence” types...

PART I - AN INTRODUCTION

What is Low Oxygen brewing? Let’s make a fundamental assumption about the malt we use in brewing: there is a malt phenolic compound that exists and gives an unoxidized wort a distinctive fresh flavor. By excluding dissolved oxygen intrusion from the beginning of the mash on, we preserve this crucial flavor component.

There may not be copious amounts of reference material that speaks to this phenolic compound directly, but we know for a fact that a distinctive flavor found prominently in Continental lager beers plays a fundamental role in the overall perception of those beers. We also know that large macro breweries take great care in many cases, particularly the large German brewhouses, in excluding dissolved oxygen from ALL stages of the process. George Fix touches on the potential presence of a low weight phenolic compound that seems to most likely be our smoking gun here. GBF Member and HBT poster Techbrau sums it up logically and succinctly in a past post from the AHA forum:

“Oxygen has more than one pathway to react with stuff in the mash. The Fenton reaction is only one of these pathways. Another set of major oxidative pathways are through naturally occurring enzymes found in the malt, such as lipoxygenase and polyphenol oxidase. I think polyphenol oxidase is the real bogeyman here, because we hypothesize that the simple, low molecular weight malt phenols are the main source of the fresh malt "it" flavor, and polyphenol oxidase is specifically made for catalyzing the oxidation of those phenols.”

So if we assume that these compounds exist and are what we are after, then their preservation becomes paramount. Once these compounds have oxidized they are gone.

So with that in mind, let’s discuss the process changes, the mechanical and chemical modifications, the gear changes and the overall concepts here. Bear with me and I’ll try and document, to the best of my ability, the whole deal from Point A to Point B.

 

[Big Monk]

PART II - THE DIFFERENCES (Hot Side)

Many people ask what are some of the key differences between Low Oxygen brewing and the more traditional homebrewing process. Quite a bit of the nuts and bolts process is the same but there are some very distinct areas where they depart from one another.

Let’s look at a quick, high level overview:

The HOT Side

Remember from Part I that we made a very educated assumption concerning the likely flavor component we are working so hard to preserve.

The biggest departure that Low Oxygen brewing makes from the traditional infusion mashing process used by home brewers is the treatment of the strike water. Most discerning brewers, even those skeptical of the effects of HSA/HSO will be taking many of the steps we advocate from mash-in/dough-in, with just a few exceptions. Where the two methods of brewing differ most dramatically, is that Low Oxygen brewing demands that the strike water be pre-treated (both mechanically and chemically) to remove all dissolved oxygen. We do this by pre-boiling the water or using the yeast de-oxygenation method coupled with targeted amounts of Sodium or Potassium metabisulfite as an active oxygen scavenger. The result is strike water with ~0 ppm of dissolved Oxygen.

Why is this important? Strike water, in most cases, is already saturated with dissolved oxygen during dough-in. The target dissolved oxygen content for Low Oxygen brewing is < 1 ppm (don’t run away scared this is ABSOLUTELY achievable) and doughing-in to saturated strike water means that you blow it before you even get started!

We also advocate underletting the mash, which many people do already. This serves to limit initial intrusion of dissolved oxygen and reduces the sulfite load. We also advocate using No-Sparge mashing but understand that vessel size limits some people. If sparging, treat sparge water like strike water.

After dough-in is finished, most people will find that they are already limiting splashing/agitation of the wort. We advocate adding some sort of a mash “cap”, typically a SS pot lid that floats on top of the mash or is fixed at the top of the mash with a gasket (there are of course many iterations worked up by our forum members), that significantly reduces exposed surface area of the mash and limits atmospheric diffusion of dissolved oxygen.

That’s essentially it. Let’s list the key points:

1.) Pre-treat your strike water:
a.) pre-boil it or use yeast method
b.) use < 30 ppm of sulfites

2.) Dough-in gently and underlet

3.) Use a No-sparge mash

4.) Stir and transfer gently to limit agitation/aeration

5.) Use a mash cap

Next time we’ll discuss the Cold side...

 

[parrothead64]

I’ve never done this before but want to give it a try. Coincidentally my copper chill it broke on my last batch I found a stainless one on letgo for 25 bucks. I Have a question, I am a BIAB brewer. Would it help to fill my bag with crushed malt and submerge it in a bucket of water that was boiled and cooled to 60F, and them slowly lower the bag into the mash? I’m thinking the water would get the oxygen out and I don’t think much conversion would happen at that temp, but I’m not sure.

 

[Big Monk]

I’ve never done this before but want to give it a try. Coincidentally my copper chill it broke on my last batch I found a stainless one on letgo for 25 bucks. I Have a question, I am a BIAB brewer. Would it help to fill my bag with crushed malt and submerge it in a bucket of water that was boiled and cooled to 60F, and them slowly lower the bag into the mash? I’m thinking the water would get the oxygen out and I don’t think much conversion would happen at that temp, but I’m not sure.

It’s not so much about O2 in the malt as it’s about the O2 added from doughing in from above with BIAB. Your bucket trick wouldn’t do anything for you. I would skip it and dough-in slowly and gently but thoroughly stir.

 

[Sbe2]

It’s not so much about O2 in the malt as it’s about the O2 added from doughing in from above with BIAB. Your bucket trick wouldn’t do anything for you. I would skip it and dough-in slowly and gently but thoroughly stir.

I had the same thought as I also BIAB.

When you pre boil don't you have to chill the water quickly to strike temp using a SS IC? Or do you let it naturally fall? I would think that O2 would be introduced if you let cool naturally.

We need a place for LoDo experts and beginners to share rationale, techniques, and results. This forum is a dedicated place to discuss this specialty part of brewing.

Ask questions, talk about your set up, make suggestions and give advice here!

+1 its like fighting through a multiflora rose patch with some of the threads on here.

 

[Big Monk]

I had the same thought as I also BIAB.

When you pre boil don't you have to chill the water quickly to strike temp using a SS IC? Or do you let it naturally fall? I would think that O2 would be introduced if you let cool naturally.



+1 its like fighting through a multiflora rose patch with some of the threads on here.

You need to force chill. Letting the water cool naturally would negate the effort.

SS is preferred. Copper with Brewtan B is a good solution as well. In fact, even after you are using a SS chiller Brewtan B is still a good choice. Copper without Brewtan B won’t negate the hot side benefits completely but it has the potential to affect flavor and stability on the cold side for sure.

 

[friarsmith]

I am a recent convert to LODO brewing. My last 7 batches were all re-brews of beers I've made several times over the years, so I have a pretty good starting point for comparison. They were 3 Euro pilsners, 2 American lagers, APA and IIPA.

The only difference was applying a few basic LODO techniques like underletting, treating my mash/sparge water w/ yeast and DME the night before brewing, adding sodium mbs to all brewing water, and using a more gentle boil than in the past. I haven't yet figured out a mash cap, but that's in the works.

In the Euro pils beers brewed recently with LODO techniques, I taste a richer and more fully developed bready Continental pils flavor. The two American lagers-- a standard Bud clone and a PreProPils-- were both brewed with 6 Row. I swear the two recent batches have a better grainy flavor. The 6 Row seems more distinct than past batches.

Pardon the esoteric road trip, but in all the beers mentioned above, there is no "edge" on the palate where the malt flavor ends and hops bitterness/flavor begins. Both ingredients seem to be more in sync than I recall in the past.

I'm a fan...

 

[Big Monk]

PART III - THE DIFFERENCES (Cold Side)

The cold side is actually where there is the most agreement between all brewers with regards to oxygen exclusion. We know that flavor stability is impacted enormously by the introduction of oxygen post fermentation. So much so in fact that most people are already very conscious and more than willing to go the extra mile.

So then, what are the differences between what we advocate and what most people are already doing? Well, there are some significant ones but nothing too expensive or insurmountable for the average brewer.

The COLD Side

One of the most frequent questions we get is, “If I just spent the time and effort excluding Oxygen, then what’s the deal with aerating/oxygenating after I pitch Yeast? Doesn’t that negate all the effort?”

The answer is NO! Firstly, we advocate no aeration/oxygenation until after ACTIVE yeast is pitched. Also, the reaction rate between the wort and oxygen is much slower at pitching temps then at mash temps. Active yeast combined with slower reaction rates means that the 8 ppm or so you’ll hit the wort with after pitching gets scavenged by the yeast in very short order. There isn’t a sufficient amount of time available for it to be damaging.

Another point of interest is chilling. You’ll want to chill the wort as rapidly as possible after knockout. Remember that the more time you spend chilling the more time your hot wort is exposed to atmospheric oxygen. In the grand scheme of things this is lower on the list but if you are taking > than 15 minutes to chill to pitching temps, we would suggest ether a new chiller or using a secondary loop with chilled water as a pre-chiller.

Now let’s talks the departures from generally accepted methods:

We advocate the use of Spunding, i.e. transferring your beer to a vessel with remaining extract and using a pressure valve set to a target pressure value in order to use naturally produced CO2 to carbonate your beer. This can be done with a keg and a Spunding valve or it can be done by bottling with extract remaining. Bottle Spunding requires you perform an FFT and use a properly rated bottle to avoid over pressurizing the static vessel.

Why natural carbonation? Well, bottle CO2, even in its most pure available form, contains enough O2 in ppm to cause the loss of freshness in your carefully prepared beer. You will have to use bottle CO2 to serve, but force carbonating is out. By using active yeast to carbonate your beer, you also ensure the finished product is oxygen free going into the serving vessel.

One caveat for those who bottle and are interested in bottle Spunding: you are bottling straight off the fermenter with active yeast remaining. This means sediment will be more than you are used to. Use 16-22 ounce bottles and take care not to stir up the yeast cake in the bottles.

One thing not mentioned explicitly that should be a given: you need to ensure your method of transferring beer from vessel to vessel is closed and that receiving vessels have been purged of oxygen. This is a big deal with kegs.

“What if I miss my window for spunding and have to ferment to final gravity” This is a frequently asked question and I think we’ll save it for a common troubleshooting post coming soon. Stay tuned.

Let’s list the key points:

1.) Chill as rapidly as possible

2.) Pitch active yeast first, then aerate/oxygenate

3.) Use Spunding either with kegging or bottling to naturally carbonate

4.) Do NOT force carbonate

5.) If kegging, ensure proper vessel purging and transfer

6.) If bottling, use conservatism (FFT, proper bottles) and use larger bottles (16-22 oz)

I wrote something in another thread that I think sums up the role of the cold side process the best:

“Think of the hot side as filling up a balloon with flavor. The cold side represents poking a hole in that balloon. How successful you are at preserving all that flavor depends on how small you can make that hole”

 

[Sbe2]

Couple of questions, can one whirlpool using LODO?

What about adding CBC-1 to the keg in order to naturally carbonate? Granted you transfer with a few pts remaining.

I am focused primarily on the cold side, but may start on the hot side.

 

[Big Monk]

Couple of questions, can one whirlpool using LODO?

What about adding CBC-1 to the keg in order to naturally carbonate? Granted you transfer with a few pts remaining.

I am focused primarily on the cold side, but may start on the hot side.

The hot side is actually the easier part.

You can whirlpool, of course.

If you transfer with active yeast, you don’t need to add additional yeast.

 

[MSK_Chess]

I always wondered about whirlpool, doesn't it surely introduce oxygen? or by that stage is it not so much of a concern as we are going to pitch anyway? I know the advice is to pitch and then aerate.

 

[Big Monk]

I always wondered about whirlpool, doesn't it surely introduce oxygen? or by that stage is it not so much of a concern as we are going to pitch anyway? I know the advice is to pitch and then aerate.

Well, it depends on how we define whirlpool.

If we are whirlpooling to centrally locate trub and break material while cooling to pitching temps, then it isn’t much of an issue. You are subject to a short duration of atmospheric diffusion.

If we are talking about quadruple hop stew IPA whirlpooling, with prolonged time at higher temps for hop stands, then it would be advisable to utilize a cap similar to in the mash.

 

[MSK_Chess]

ok makes sense. Cheers Scotty

 

[MSK_Chess]

I was searching for PVPP in the boil and found this. I think it was uploaded by you guys. Makes very interesting reading. I do use PVPP and silica gel post fermentation and had never considered that PVPP could be used just at the end of the boil (3min). It seems that a mixture of PVPP and Gallotannins, a slightly lower mash PH of 5.0 - 5.2 really has a profound effect on the freshness, the stability and the presentation of beer. I love bright beer. Article is a must read. Would be good if someone could interpret the scientific data and convey it in laymans terms and make practical application.

http://********************/wp-content/uploads/2017/02/Officiele_tekst_voor_Brewing_Science.pdf

 

[Dland]

Could someone please define "underletting" in reference to dough in practices. I seem to have missed that.

I'm thinking it might be to pump strike water into bottom of MT with grain already in it, but wouldn't that require a lot of stirring?

 

[mongoose33]

Could someone please define "underletting" in reference to dough in practices. I seem to have missed that.

I'm thinking it might be to pump strike water into bottom of MT with grain already in it, but wouldn't that require a lot of stirring?

You put your crushed grain in the MT, then fill from the bottom up, either by pumping or gravity. I've done both.

No stirring. No dough balls. I always poke a spoon down into the grist toward the end just to ensure it's all gotten wet, but usually no need. I will then gently--GENTLY--stir once all the water is moved to the mash tun, then add back the mash cap.

************

I use a pump now add the water (needs to pump uphill), but I've also had the strike water up high and used a tube to move that to the bottom of the mash tun. Both work fine.

I've settled on a pace of between a quart and 2 quarts a minute; toward the end, when the grain is submerged, I'll up the flow rate.

 

[Dland]

Well, I just mashed in underletting, started with gravity, but turned on a pump at end to get some mix up. I did have a few dough balls, but nothing gentle stirring did not fix. It is physically easier than poring the grist on top of the water while stirring, 23# grain bill. One of my high ABV CAPs.

I did condition the grain, that was easy enough. Did not pre boil, no time for that today. Two questions about this:

When you heat water up to strike temp, a lot of small bubbles leave the water, is at least some of that dissolved 02?

If I were to put some yeast and a little DME in my brewing water the day before, would that remove any 02?

Back to my brew.

 

[GoeHaarden]

I use a pump now add the water (needs to pump uphill), but I've also had the strike water up high and used a tube to move that to the bottom of the mash tun. Both work fine

Wouldn't pumping your strike water negate any prior de-oxygenation?

I knew I shouldn't have opened this damn LoDo thread. Very intrigued! Down the rabbit hole we go now...

 

[tgodsill]

Dland, I'm not 100% on this but I believe a dosing rate of 2g dextrose (corn sugar) and 2g bread yeast per gallon of brewing water. This thread details the procedure. http://forum.germanbrewing.net/viewtopic.php?f=50&t=355#p3022

 

[mongoose33]

Wouldn't pumping your strike water negate any prior de-oxygenation?

Why?

There are no bubbles in the line, so no place for O2 to enter. Even if the pump were cavitating, which I don't believe it is, there's no O2 involved.

I'm always adding some potassium metabisulfite in the form of Campden tablets (1.5 tablets crushed) to my strike water. It's an oxygen scavenger, and the purpose is to bind to any oxygen that makes it into the mash. I don't have a perfect system (who does?), so I'm trying to limit oxygen as much as possible--but I can't get it all. The KMBS is there to get what gets past my process.

For instance, I use a mash cap, but I also stir a couple times during the mash--gently, gently. Even so, the surface of the mash is in contact w/ the atmosphere, which contains oxygen. So the KMBS is there to help me deal with that.

I knew I shouldn't have opened this damn LoDo thread. Very intrigued! Down the rabbit hole we go now...

You have no idea...

 

[GoeHaarden]

There are no bubbles in the line, so no place for O2 to enter. Even if the pump were cavitating, which I don't believe it is, there's no O2 involved

Can you elaborate on how you do this a little more? I guess I'm thinking about what happens when you prime the pump, obviously there is air in the line before this. Guess that is unavoidable, and probably a trivial amount of O2 ingress? Do you use the yeast method?

Another question. Would it be worth the efforts in a decocted beer? I have an Oktoberfest on deck to brew and I'm going to decoct, but I think I would like to implement some of these LoDo strategies...

 

[mongoose33]

Can you elaborate on how you do this a little more? I guess I'm thinking about what happens when you prime the pump, obviously there is air in the line before this. Guess that is unavoidable, and probably a trivial amount of O2 ingress? Do you use the yeast method?

When I prime my pump--it's a Blichmann Riptide with a priming valve at the pump head--the water comes through the line and, at the very start of the water, it IS in contact w/ air. I don't purge my pump lines but I could, and I believe some people do. But it's a very small amount of air, too small with which to concern myself. As you say, a trivial amount.

And that's the point of the Campden tablets--I can't be perfect, so they are there to clean up anything that gets past my process.

I just preboil the water and then chill it down to strike temp using a stainless immersion chiller. THE toughest thing to do is to get that water to the right temp. I boil it on a Blichmann Hellfire, and there's residual heat that enters the water after chilling....so I'm trying to balance the residual heat and the chilling. I can always turn on the burner for a minute if I overshoot the temp to the downside.

Another question. Would it be worth the efforts in a decocted beer? I have an Oktoberfest on deck to brew and I'm going to decoct, but I think I would like to implement some of these LoDo strategies...

I doubt it would hurt. If you're boiling the decoction then that boiling should be driving off O2.

I think there's value in doing some of this even if you don't do all of it. However, if at any point you allow significant O2 ingress, you're going to negate the earlier work on eliminating O2.

An interesting way to examine this is to do a mini-mash with maybe just a couple pounds of grain. Do LODO techniques with it--preboil the strike water, use a mash cap, underlet. Then at the end of an hour, taste the wort. My guess is you'll be shocked at what you taste.

Then do it again, with no concern for restricting O2 at all. In other words, normal process. See if you can tell the difference. If you can, then the next step is getting the wort from mash tun to kettle w/o screwing up what you did. I drain the mash tun into the kettle using gravity, a thin silicone tube running to the bottom of the kettle so no splashing. I use a lauter cap on that wort to prevent O2 ingress during lautering and while it's coming up to a boil. Once boiling, we're driving off O2 again.

Please don't confuse me with an expert on this issue. I've been doing it since about November, and the above notes are my understanding of the process.

Here's what my lautering and lauter-cap setup looks like:

 

[GoeHaarden]

Here's what my lautering and lauter-cap setup looks like

Thanks for all the info. I think I'm definitely going to do some of these techniques. Im trying to decide what I can get away with using my current cooler setup. Haven't been motivated to rebuild my RIMS controller. I do think preboil, underlet, and mash cap seem like easy things to employ. I am curious to see how it changes the flavor.

Do you do full volume no sparge mash?

 

[Dland]

My brew today had about a 10% reduction in mash efficiency than I usually get, the only difference was the underlet strike. I guess I probably had more dough clumping than I thought. Next time going to pump the strike water in instead of gravity feeding. I thought the slower rate would be good, but I guess not.

 

[schematix]

My brew today had about a 10% reduction in mash efficiency than I usually get, the only difference was the underlet strike. I guess I probably had more dough clumping than I thought. Next time going to pump the strike water in instead of gravity feeding. I thought the slower rate would be good, but I guess not.

Did you stir really well ? You must still stir even if underletting.

I underlet, and stir, and always get 100 % conversion.

 

[Dland]

I guess I did not phrase that right. I think I got good conversion, but the sparge was not efficient. I used normal procedure, but my last runnings were at 1.028, usually they are lower. The sparge did not stick, but there was not an even flow though it apparently. Hopefully the vigorous pump in will suspend the mash better in the water, mash tun made from upside down keg, so it flows from bottom nicely.

 

[GoeHaarden]

For those of you using Campden Tablets to scavenge O2...

So, I understand that you add it to the strike water, but do you account for it in your water adjustments somehow or just ignore it in that sense? I always build up distilled water. Also when do you add it, preboil or after cooling the strike water?

Cheers!

 

[aeviaanah]

I was searching for PVPP in the boil and found this. I think it was uploaded by you guys. Makes very interesting reading. I do use PVPP and silica gel post fermentation and had never considered that PVPP could be used just at the end of the boil (3min). It seems that a mixture of PVPP and Gallotannins, a slightly lower mash PH of 5.0 - 5.2 really has a profound effect on the freshness, the stability and the presentation of beer. I love bright beer. Article is a must read. Would be good if someone could interpret the scientific data and convey it in laymans terms and make practical application.

http://********************/wp-content/uploads/2017/02/Officiele_tekst_voor_Brewing_Science.pdf

Interesting link, thanks for sharing.

What is polyvar? Is this a coagulant similar to whirlfloc

I typically mash at 5.2-5.4. I wonder if I should lower a bit?

It’s interesting they chose such low contact times for gallotannins. I use in the HLT and have never used in the boil. This puts my contact time much more then the stated 3-5min. I don’t use In kettle as my system is 100% stainless. How do you use gallotannins?

 

[MSK_Chess]

Polyclar 730 is a silica gel and a PVPP.

 

[specharka]

I'm looking to dip my toes into the water here.
I already practice all of the cold side techniques; I ferment in kegs, spund, and closed transfer the beer to my serving keg.
I want to try adapting the hot-side LoDo techniques to my Grainfather brewing system. I think I can achieve the < 1 ppm DO on the strike and perform a pseudo-underletting by lowering the mash basket gradually into the strike water.
I'm wondering if any LoDo acolytes out there know of a way to adapt the mash cap concept to the Grainfather.

 

[GoeHaarden]

So just started my mash using preboil/underletting/mash cap. Couple of questions.

1. How long do you preboil your strike water prior to chilling/underlet? I did 5 minutes.

2. Why the hell does my mash look so murky with underletting?

 

[MSK_Chess]

I think 5 mins is the recommended amount if time. I cannot say why it looks so murky. Are you recirculating? If so it should clear up and you also might want to consider grain conditioning.

 

[GoeHaarden]

I think 5 mins is the recommended amount if time. I cannot say why it looks so murky. Are you recirculating? If so it should clear up and you also might want to consider grain conditioning.

Nope, not recirculating. I say murky, but I guess a better adjective would be "milky" or whiter than normal. I don't think it will effect anything, it's just weird or different shall I say!?

What bisulfates would you recommend? And how much? I don't think I'm going to do it impulsively on this mash, but just curious for future brew

Thanks!

 

[mongoose33]

So just started my mash using preboil/underletting/mash cap. Couple of questions.

1. How long do you preboil your strike water prior to chilling/underlet? I did 5 minutes.

2. Why the hell does my mash look so murky with underletting?

I boil for 5 minutes, then chill using a stainless immersion chiller.

As to your mash: did you stir at all? When I underlet the grain sits below the liquid surface; I'm doing a modified BIAB approach, no sparge, just 8.25 gallons of strike water for a 5-gallon batch. So my grain is sitting a couple inches below the surface of the liquid, and I'll gently stir it. No recirculation at this time (it's on the horizon).

 

[GoeHaarden]

I boil for 5 minutes, then chill using a stainless immersion chiller.

As to your mash: did you stir at all?

Yes, I did stir to ensure temp was consistent throughout. I used a copper immersion chiller. I know I've read something about copper releasing metals or something, but it's all I really have...


EDIT: I'm going to be batch sparging, but plan to boil/chill/underlet as well.