Interesting German Brewing PDF

[beernutz]

Actually it isn't at all. That's why we have double blind triangle tests!

Here I have a second opportunity this week to tell a favorite story of mine in this regard. About 3 yrs ago I was asked to write a chapter on beer color for a book Charlie Bamforth was doing (the final proof just went out today - hurrah). At right about that time ASC sent me a notice of a webinar in which Charlie was the featured speaker and the subject was beer color. Seemed to me it would be a good idea to watch that webinar and I did. In it he said "we taste with our eyes". I think everybody knows that but I was shortly after that invited to a gathering at which many of the local beer cognoscenti ((pro's, Master judges....) were to be present. I took two growlers containing similar lagers. One was darker than the other. I asked for criticism and comparative comments from several of these people and the distinctions they were able to draw astounded me. How much richer the dark beer was, how the one had more vanilla notes and on and on. One little lady asked if she could try nd upon tasting the two apologetically explained that she really didn't know anything about beer and was just accompanying her boyfriend but that she really couldn't taste any difference at all. I expect that you have figured out what the deal was by now. The emperor had no clothes. It was the same beer in the two growlers with a little Sinamar (I don't think the color difference could have been as much as 5 SRM). When my duplicity was revealed several people were pretty angry. One guy didn't speak to me for over a year and I didn't get invited back.

The point is, of course, that if you want to taste something badly enough, you will. As I said at the outset, this is widely enough appreciated that we use double (yes, even telegraphing of the 'right' answer to the taster can be a problem - look up der Kluge Hans) triangle tests with the triangle part being there to be sure the taster can correctly detect that there even is a difference.

So I think the guys are absolutely right to express the healthy skepticism that they have shown here. The devotees speak of the technique with almost religious fervor and wherever one sees that he is well advised to step back and say "Well let's see." Quotation from the Holy Books is often used in support of hypotheses such as the current one and I note that his is being done here. Kunze's book contains at least one glaring error (which the aforementioned Charlie Bamforth propagated by quoting in a fairly recent paper) and in fact he has very little to say about oxygen exclusion from mash including a statement to the effect that one should not minimize the oxygen content of a mash but rather reduce it.

None of this is to say that I think the thesis is a bad one. To some extent it makes sense. But you really want people to question and challenge and even try to prove you wrong. If you are on solid ground you will be vindicated.

I am curious about the last part of your sentence where you write that Kunze states that the oxygen content of a mash should not be minimized. If Kunze himself is not concerned with minimizing oxygen in the mash then what's all the hubbub?

 

[doug293cz]

This is what I was getting at, but you said it a heck of a lot better than I did. In addition, length of exposure comes into play as well, does it not? ie, the exposure in a half-full keg over a day's time has a different effect than the same keg over the course of a week or two? If I dispense all of my beer at once it certainly would not be the same as if I dispense it over the course of a month, no?

I'm just trying to get to the point where I can understand overall net benefit. If the extra effort (krausening, spunding valve, etc) of natural carbing goes out the window when my half-full keg sits idle for a week with commercial CO2 sitting on top of it, then I haven't gained anything.

Yes time certainly has a lot to do with it. Both for O2 absorption rate into the beer, and O2 reaction rate with compounds in the beer.

One thing the folks overlook about the "30 ppm" of O2 in food/beverage grade CO2, is that's the upper limit specification, not an actual measurement. I was googling around a couple days ago, and found a purported actual measurement of O2 in food/beverage grade CO2 -- 0.25 ppm! (sorry didn't keep the link.) So the 30 ppm just tells you what the worst case can be.

Brew on

 

[TheHairyHop]

You guys have been getting a lot of compliments, criticism and opinions. (edit: I appreciate the work you undertook to write this article and your generosity to share it) To add my own request, I think it would behoove you to do DO measurements to some serving kegs and report on it. I expect some converts on this site will be able to, but at a later date. I imagine it takes time to dial in a system.

 

[Edelst0ff]

Yes time certainly has a lot to do with it. Both for O2 absorption rate into the beer, and O2 reaction rate with compounds in the beer.

One thing the folks overlook about the "30 ppm" of O2 in food/beverage grade CO2, is that's the upper limit specification, not an actual measurement. I was googling around a couple days ago, and found a purported actual measurement of O2 in food/beverage grade CO2 -- 0.25 ppm! (sorry didn't keep the link.) So the 30 ppm just tells you what the worst case can be.

Brew on

It's a very good point and a huge concern. IIRC Lagers here in Europe are pushed with a 40/60 mix od co2/N.

The consensus is that it tastes much better.

Hope this helps

 

[dsniegocki]

Well beergas of some type... sure. That has the added advantage of eliminating any chance of over-carbonation on a higher-pressure run. If a beergas or nitro mix of some type fixes this issue, then that seems to make the natural carbonation much more worthwhile.

Not sure whether that's a switch I'm ready to make yet. I'll prolly scour the threads to see how feasible that may be to do on a homebrew scale. I can get CO2 filled easily, but not sure how available a nitro or beergas tank would be to me. Would be nice to bump up the dispense pressure as I've got a bit of a run from keg to tap.

Not trying to sidetrack this thread from the HSA stuff, but to me anyway I get the impression that the cold side effects are more easily detected by the flavor, and more easily controlled... for me at this time FWIW. One step at a time. : )

 

[ajdelange]

I am curious about the last part of your sentence where you write that Kunze states that the oxygen content of a mash should not be minimized. If Kunze himself is not concerned with minimizing oxygen in the mash then what's all the hubbub?

There were a couple of points in that post. First off, no one can claim that Kunze was an advocate of 0 oxygen as he clearly stated that some oxygen exposure is desirable. The second is that while Kunze was no slouch WRT brewing science he did make a mistake regarding the buffering of malt phosphate and Charlie Bamforth, who is also pretty good at this stuff, propagated it with the overall point being that even the expert among the experts can be wrong in some of their opinions. This isn't very comforting, I'm sure, to those who want unassailable answers but that's the way life is.

 

[indevrede]

First, I'd like to thank rabeb25, techbrau & the other authors of the pdf from the original post in this thread. They clearly did a lot of reading, analysis, brewing, and measurement and I'm grateful for the time and effort they've spent in not only coming up with the "LoDO" technique, but in explaining and advocating it on this and other fora.

After I read the paper I decided to try the technique on a Bavarian Weissbier. I set aside my two beautiful copper Chillzillas and replaced them with a DIY 50-foot 3/8 stainless CFC (a chore to make) and replaced every other brass and copper fitting with stainless. I followed the instructions closely (conditioned milled malt, pre-boiled RO + CaCl strike water, quickly chilled, 100 ppm Sodium Metabisulfite, underlet full volume mash, <10% boil-off, chilled, pitched, oxygenated, fermented, transferred to CO2-purged keg with little headspace, and spunded. I left the keg at room temperature for a few days for the yeast to finish cleaning up and reach FG.

The one mistake I'm aware of was oxygenating with pure O2 for 60 seconds after pitching (apparently it's important to oxygenate more slowly, to give the yeast time to absorb). When I oxygenated I smelled burnt matches (SO2). Another shortfall: I do not have a DO meter.

I brewed this on Memorial Day (May 30th) and the initial tasting impression is that the beer is (nearly) undrinkable due to a strong sulfur (H2S, rotten egg) smell. My previous (non-LoDO) fermentations with WY3068 have smelled like sulfur during primary fermentation, but by kegging it was generally gone. To be clear: I'm not criticizing the authors or giving up on the LoDO technique, I'm just disseminating my early result.

I have a Helles fermenting now (50 ppm SMB) and I'm going to try an Irish Stout this weekend. I'll post the results when I have them.

 

[Edelst0ff]

Initially I bought a DO meter for excactly that purpose, controlling the o2 level when aerating the wort. It's very easy to overshot by quite a factor when using pure o2. As far as Weizen is concerned it's probably best to just use the o2 in the headspace of the fermenter rather than having 35 mgl of o2 in there. It happens surprisingly fast.

I never had that problem you had though. Did you use lab yeast or repitch (this symptom could be an infection)?

I did many geat wheat beers pre Lodo. What I noticed was that Lodo pushed it a few subtle notches up as far as the caramel flavours are concerned. So it's worth persisting. One never gets things right the first time. I'd recommend a do meter when working with pure o2 though. It's really quick to overshoot multiple times.

Brew on!

 

[indevrede]

I made a 1 liter starter from a Wyeast smack pack. Contamination may have been a problem, but I would be very surprised.

 

[TheHairyHop]

Pitching 20 to 30 million cells per ml, at what point do you even need o2? I've thought of zero o2 pitches for IPAs, especially with wlp644

 

[germanbrewing]

I made a 1 liter starter from a Wyeast smack pack. Contamination may have been a problem, but I would be very surprised.

Nothing in what you did sounds like a specific culprit to zero in on (from my experience). Give it some more time. With spunden (and cold) fermentation, I'm re-finding my way on fermentation. More than anything mash related.

 

[Edelst0ff]

Pitching 20 to 30 million cells per ml, at what point do you even need o2? I've thought of zero o2 pitches for IPAs, especially with wlp644

For lager that's the right cell count.

For ales this is too high.

I did this mistake once. The end result was a beer that was way too yeasty tasting with a not so nice nose.... It was as if someone farted in the bottle.

Maybe this is why the wheat beer didn't turn out right?

Over pitching by 100% really isn't a good idea. I never thought it would have such drastic effect until I made the mistake.

 

[indevrede]

For lager that's the right cell count.

For ales this is too high.

I did this mistake once. The end result was a beer that was way too yeasty tasting with a not so nice nose.... It was as if someone farted in the bottle.

Maybe this is why the wheat beer didn't turn out right?

Over pitching by 100% really isn't a good idea. I never thought it would have such drastic effect until I made the mistake.

Wait, what? A 1 liter starter in a 5 gallon batch is overpitching?

Side note: "farts" is an apt description.

 

[TheHairyHop]

Wait, what? A 1 liter starter in a 5 gallon batch is overpitching?

Side note: "farts" is an apt description.

the article suggests a pitching rate much higher than what a 1 liter starter will get you. unless 20-30 million per ml was a typo

wait nvm, I was reading my pitch calculator wrong

 

[dstar26t]

the article suggests a pitching rate much higher than what a 1 liter starter will get you. unless 20-30 million per ml was a typo

I think there's confusion between pitching a Helles at 5-6ºC according to the paper and pitching a Hefeweizen that Indevrede brewed that he probably pitched at 15ºC+. 10-18 million/mL (.75-1.5 million/mL/ºP) would be more like it for a Hefe depending on the phenol level you prefer...1L stirplate starter would have been just barely ok for 5 gallons, IMO.

 

[JasonG]

I didn't find this mentioned in the thread or in the PDF, but if I missed it I apologize. What DO meter are you all using? I have been very interested in getting one, but have had trouble finding one at a reasonable price. Any recommendations?

JG

 

[Edelst0ff]

Wait, what? A 1 liter starter in a 5 gallon batch is overpitching?

Side note: "farts" is an apt description.

It's best to keep it in cell count range to avoid confusions.

For wheat beer the cell count is 5-15 million cells per ml. If you use volumes like for lager, then you most definitively over pitched. That yeasty, fart whiff is most definitively an indication that this is what may have happened.

 

[Edelst0ff]

I didn't find this mentioned in the thread or in the PDF, but if I missed it I apologize. What DO meter are you all using? I have been very interested in getting one, but have had trouble finding one at a reasonable price. Any recommendations?

JG

I recommended the extech DO600 to techbrau and rabeb25 back then. They were very happy with it and kept recommending it to others.

 

[indevrede]

It's best to keep it in cell count range to avoid confusions.

For wheat beer the cell count is 5-15 million cells per ml. If you use volumes like for lager, then you most definitively over pitched. That yeasty, fart whiff is most definitively an indication that this is what may have happened.

So we're clear: For the Weissbier (1 liter starter), my pitch rate was 5 million cells per mL. I targeted low according to the wisdom of the interwebs.

The smell is not "yeasty", it's egg-sulfur-fart. H2S, I believe.

Side note: Early result from the Helles I brewed on Tuesday (3 days into attenuative phase @ 8 deg C, pitched ): Intense sweet malty aroma, zero sulfur. For this Helles I reduced the SMB from 100 ppm to 50 ppm, compared to the Weissbier.

 

[TheHairyHop]

It sounds like your smb or its byproducts may have reacted with something in your process

 

[Edelst0ff]

Indeed, that's a possibility as well. I always argued to only use as much as necessary.

Without a DO meter it's difficult to adjust for one's system.

Pitching rate looks fine.

I'd lower my SMB dosage for wheat beer then.

The most important bit is to have Degassed water at dough in - as far as I can tell. This works very well with bottom fermenting yeasts. For wheat beer this may be a different animal.

Sadly, we don't have the means for exact analysis and are flying blind and by trial and error.

I made some lovely wheat beers with 50 mgl SMB.

Fermentation temperature may also be a factor, but that's a wild guess.

I ferment my wheats around 18C and enhance the 4-vinyl guaiacol (if desired) by means of a maltase mash.

I'd lower the SMB first.

 

[jddevinn]

So we're clear: For the Weissbier (1 liter starter), my pitch rate was 5 million cells per mL. I targeted low according to the wisdom of the interwebs.

The smell is not "yeasty", it's egg-sulfur-fart. H2S, I believe.

Side note: Early result from the Helles I brewed on Tuesday (3 days into attenuative phase @ 8 deg C, pitched ): Intense sweet malty aroma, zero sulfur. For this Helles I reduced the SMB from 100 ppm to 50 ppm, compared to the Weissbier.

Hey, just a question... did you reduce the sparge water to 10-25ppm SMB? I missed this on my original (2) readings of the paper as I normally make all Hot Liquor I need at one time. In my planned attempt to try this I will need to separate my strike water from my sparge water as they will require different SMB concentrations.

 

[indevrede]

I'd lower my SMB dosage for wheat beer then.
...
I made some lovely wheat beers with 50 mgl SMB.

OK, I will try 50 ppm next time.

Hey, just a question... did you reduce the sparge water to 10-25ppm SMB?

No-sparge (lower efficiency but simpler hot-side processing for me).

 

[Iseneye]

Did my first lodo on Saturday (APA no dry hop). Had a nightmare of a time. Steel mash cap was held up by sitting on silicone tubing. Tubing softened and cap sank down. I didn't have much head room anyway (BIAB no sparge). Then burner blew out at t30 boil in wind and couldn't get going for around 10 minutes.

I am doing full lodo process. Boil then chill, smb, mill conditioned grains, mash for 60. Raise bag gently (I got zero splashing so BIAB seems good to me). Simmer boil for 60, chill , put 1l yeast starter at high Krausen into 23l keg and drain kettle directly onto yeast. Let sit for 30 min then did three 20 sec blasts of O2 at 30 min intervals.

Im using techbraus fermenting setup which is fermenting keg hooked to serving keg gas out to beer in line with spunding valve on receiving keg at 2 to 3 psi.

I forgot to taste mash but did taste before pitching. It is a completely different flavour. It's super sweet and kinda tastes like honey. Basic grain bill of base plus med crystal and carapils. The taste makes me think I was successful. I had a DO meter but the one they sent was faulty and being replaced. I'll only be able to test final product but confident I'll reach the low O2.

 

[ParanoidAndroid]

Did my first lodo on Saturday (APA no dry hop). Had a nightmare of a time. Steel mash cap was held up by sitting on silicone tubing. Tubing softened and cap sank down. I didn't have much head room anyway (BIAB no sparge). Then burner blew out at t30 boil in wind and couldn't get going for around 10 minutes.

I am doing full lodo process. Boil then chill, smb, mill conditioned grains, mash for 60. Raise bag gently (I got zero splashing so BIAB seems good to me). Simmer boil for 60, chill , put 1l yeast starter at high Krausen into 23l keg and drain kettle directly onto yeast. Let sit for 30 min then did three 20 sec blasts of O2 at 30 min intervals.

Im using techbraus fermenting setup which is fermenting keg hooked to serving keg gas out to beer in line with spunding valve on receiving keg at 2 to 3 psi.

I forgot to taste mash but did taste before pitching. It is a completely different flavour. It's super sweet and kinda tastes like honey. Basic grain bill of base plus med crystal and carapils. The taste makes me think I was successful. I had a DO meter but the one they sent was faulty and being replaced. I'll only be able to test final product but confident I'll reach the low O2.

How did you raise your bag? I'm BIAB and am following this thread. I read where someone had a pulley and just raised the bag about an inch at a time which reduced splashing. They didn't squeeze the bag either, which I would think you would need to account for a 10-20% drop in efficiency.

 

[TexasWine]

How did you raise your bag? I'm BIAB and am following this thread. I read where someone had a pulley and just raised the bag about an inch at a time which reduced splashing. They didn't squeeze the bag either, which I would think you would need to account for a 10-20% drop in efficiency.

I used a ratchet pulley and just pulled a fraction of an inch at a time. No squeeze, and I'm usually a squeezer. My efficiency did not drop because I let the bag drain sufficiently before moving it to the side.

 

[ParanoidAndroid]

I used a ratchet pulley and just pulled a fraction of an inch at a time. No squeeze, and I'm usually a squeezer. My efficiency did not drop because I let the bag drain sufficiently before moving it to the side.

You were probably the one I was thinking about then.

That's good news on the efficiency. How long did the total drain take? How long did you let each pull drain? I'm only doing 3.25 gallon batches, so my grain bill isn't the normal 5 gallon batch size.

 

[TexasWine]

You were probably the one I was thinking about then.

That's good news on the efficiency. How long did the total drain take? How long did you let each pull drain? I'm only doing 3.25 gallon batches, so my grain bill isn't the normal 5 gallon batch size.

Didn't time the total drain time. I pulled it from the kettle just before the boil started, so maybe 20 minutes.

Time between pulls varied too. At first the liquid comes out rapidly, then it slows. I'd say on average 45 seconds to a minute at the beginning.

 

[TexasWine]

Cargill has developed a specialty malt to combat oxidation.

http://www.cargillfoods.com/wcm/groups/public/@cseg/@food/@all/documents/document/na3051727.pdf

 

[jddevinn]

Cargill has developed a specialty malt to combat oxidation.

http://www.cargillfoods.com/wcm/groups/public/@cseg/@food/@all/documents/document/na3051727.pdf

Hmm, this is interesting. From their data LowLOX Malt doesn't do anything to stop oxygen uptake. What they did was selectively breed 2-row to come up with a strand that does not contain the lipoxygenase (LOX) enzymes. The iron containing LOX is required to form the acids that are a precursor, along with oxygen, to trans-2-nonenal. The trans-2-nonenal that is created is bound to proteins and sulphites and is slowly released during storage. It is what causes the "cardboard" oxidation flavor at concentrations above 0.1ppm.