Interesting German Brewing PDF

[Cavpilot2000]

Last batch I racked to 3 gallon keg after fermentation in 5 gallon keg, etc..... however, I had a gallon or a bit left in the primary keg..... I put it in the fridge and figured I would just drink some glasses off it so as not to let it go to waste - I was STUNNED by how good that beer was after about 4-5 weeks from brew day (Sitting on yeast/ferment) the entire time. Clear as glass, super fresh and crisp.

I have a pilsner and Ofest going the same way right now. New plan is to leave it all in that primary longer and wait to jump it to 3 gallon keg until around 4 weeks (just really seemed to clean up so much better with a bit more time on the yeast.) I will then attempt to bottle the gallon or so that does not fit in my 3 gallon keg to see how that holds up.

Yeah, I've had the best results when not being in a hurry to rack.
I think we've all got this fear of autolysis in our heads from the old timers who used to say anything more than 2 weeks on the lees and you run the risk of off-flavors. Healthy yeast, even dormant yeast, is our friend, and especially at lager temps, I find zero problem with sitting on the lees a month or more, and in fact some positive results (I suspect they are still doing their oxygen scavenging bit, albeit on a much smaller scale).

 

[rabeb25]

If you are not careful you will start to see autolysis after about the 3 month mark. It won't present itself like you think it will though. It will be a slight yet steady decline in flavor, a pH reading would show you a raise as well.

 

[Braufessor]

If you are not careful you will start to see autolysis after about the 3 month mark. It won't present itself like you think it will though. It will be a slight yet steady decline in flavor, a pH reading would show you a raise as well.

3 months...... that would never, ever be a problem with a beer that tasted as good as this last one did. It would never last that long I was just so surprised how clean, clear, crisp it was.... at only 4 weeks old it was "ahead" of a very similar beer that I moved into a serving keg at about 2-2.5 weeks.... and that beer was closer to 8 weeks old. More time on the yeast certainly seemed to benefit it that was for sure. Eager to see if that carries through and repeats itself on the two I currently have fermenting.

 

[friarsmith]

I found the paper to be informative and thought-provoking. After almost 20 years of brewing, I've been looking for additional ways to tighten-up my process and continually improve my lagers to hopefully be happier with the results and maybe even convert some 2nd's and 3rd's to 1st's. I'm going to start using as many of the recommendations as possible when I fire up the brew house this fall. Ya never know, I think the recommendations can't hurt at least.

One random question: Regarding underletting to fill the mash tun. Does anyone have experience doing this w/o a pump? Is it possible? Meaning, if I have a kettle w/ hot strike water sitting a few feet above the mash tun (filled w/ dry grain), would gravity be enough to fill the mash if I run some hi-temp tube from the valve of the HLT to the valve at the bottom of the mash? I have a pump, but I'm curious if it's absolutely necessary for this step. Not sure if the back-pressure of the slowly wetting grain would stop the flow...

 

[Jwin]

I found the paper to be informative and thought-provoking. After almost 20 years of brewing, I've been looking for additional ways to tighten-up my process and continually improve my lagers to hopefully be happier with the results and maybe even convert some 2nd's and 3rd's to 1st's. I'm going to start using as many of the recommendations as possible when I fire up the brew house this fall. Ya never know, I think the recommendations can't hurt at least.

One random question: Regarding underletting to fill the mash tun. Does anyone have experience doing this w/o a pump? Is it possible? Meaning, if I have a kettle w/ hot strike water sitting a few feet above the mash tun (filled w/ dry grain), would gravity be enough to fill the mash if I run some hi-temp tube from the valve of the HLT to the valve at the bottom of the mash? I have a pump, but I'm curious if it's absolutely necessary for this step. Not sure if the back-pressure of the slowly wetting grain would stop the flow...

I would think you would be okay, but only one way to know. If you have a pump, there's not much risk in trying.

 

[Cavpilot2000]

I found the paper to be informative and thought-provoking. After almost 20 years of brewing, I've been looking for additional ways to tighten-up my process and continually improve my lagers to hopefully be happier with the results and maybe even convert some 2nd's and 3rd's to 1st's. I'm going to start using as many of the recommendations as possible when I fire up the brew house this fall. Ya never know, I think the recommendations can't hurt at least.

One random question: Regarding underletting to fill the mash tun. Does anyone have experience doing this w/o a pump? Is it possible? Meaning, if I have a kettle w/ hot strike water sitting a few feet above the mash tun (filled w/ dry grain), would gravity be enough to fill the mash if I run some hi-temp tube from the valve of the HLT to the valve at the bottom of the mash? I have a pump, but I'm curious if it's absolutely necessary for this step. Not sure if the back-pressure of the slowly wetting grain would stop the flow...

I do it. In fact, I do multi-step mashes, underletting via gravity feed from my kettle to my cooler-type mash tun.
Details:
The initial dough-in is no problem. I leave the kettle on the burner and put the MT on the floor and let gravity do its thing.
Occasionally on subsequent infusions, especially the third and later, the height differential is not enough to overcome the hydraulic pressure in the MT, especially if I've let the kettle drain in the previous infusion and the dip tube is full of air. It's hard to explain with words, but the dip tube in the kettle and the hose leading to the MT are then filled with air, and there isn't enough pressure to push the air bubble through into the MT with all the water pressure in the MT.

Just this weekend, I overcame that problem by leaving just enough water in the kettle to keep the dip tube opening covered (about 1-1. quarts). This prevents the dip tube and hose becoming filled with air, and whwn I added infusion water and preboiled boiled it, it transferred easily for the infusions.

If you need additional explanation or if this was confusing, let me know.

Bottom line is it works, but you may run into complications if you do multi step infusion mashes (but I have figured out how to overcome them and will gladly help).

 

[Bilsch]

One random question: Regarding underletting to fill the mash tun. Does anyone have experience doing this w/o a pump?

I also use gravity and actually prefer it because it's slow and calm. With about 3' head and a valve in the line to regulate the flow, it takes about 10 minutes to move 6 gallons. That way there is little or no trapped air in the grainbed.

 

[Iseneye]

I did..
I brewed yesterday with some tests. Here is what I saw.
DO with yeast deoxygenation

Thanks for the detailed reply rabeb. I went for a run today and had questions popping in my head:

What was your SMB rate in the standard batch and in the BIAB batch? Your meter indicates that more O2 is getting into the BIAB batch (more on that later). My response would be that the BIAB batch requires more SMB to counter that. I've got no idea on how to do the numbers but I have always assumed that BIAB requires a higher dosage rate than underletting. My first batch was 100ppm no sparge and was way too much and could taste it in the finished beer. Second batch I dropped down to 50ppm and I couldn't taste any residual. I have seen on here that ales should be around 30ppm and lagers 50ppm. Throwing random numbers out there for BIAB you may need to go to 50 and 75 or whatever works for the system.

I'm not going to be the annoying guy who says "do a triangle test" but did you have anyone else taste the two batches? I think it is fair to say that you would have expected a difference so are biased (no offence intended). Did you do a blind test on yourself or has anyone else tasted it and come to the same conclusion?

I have commented on it before but IMHO the readings you get from the Extech O2 meter are useless for readings around the 0-1ppm mark. The spec sheet states basic accuracy +/- 0.4ppm. Who knows what basic accuracy means but let's assume it is one standard deviation. If you went to a 95% CI it will be higher than +/- 0.4ppm. I say all this and have the DO600 myself. I find it useful for measuring oxygenation levels post pitch but don't trust it for the key <1ppm readings.

 

[oujens]

I also use gravity and actually prefer it because it's slow and calm. With about 3' head and a valve in the line to regulate the flow, it takes about 10 minutes to move 6 gallons. That way there is little or no trapped air in the grainbed.

Is it recommended to transfer that slow? What's the temp difference between strike water and mash temp needed to hit your target mash temp? I'm adding a pump to my setup but am thinking I want to gravity feed my mash tun.

 

[Bilsch]

Is it recommended to transfer that slow? What's the temp difference between strike water and mash temp needed to hit your target mash temp? I'm adding a pump to my setup but am thinking I want to gravity feed my mash tun.

I lose about 9 degrees between the HLT and the mash over that time but then my tun is insulated. It could probably go faster and not be a problem but this is what works well for me. I feel it's important to keep entrained air at an absolute minimum so I go slow.

 

[Bilsch]

I have commented on it before but IMHO the readings you get from the Extech O2 meter are useless for readings around the 0-1ppm mark. The spec sheet states basic accuracy +/- 0.4ppm. Who knows what basic accuracy means but let's assume it is one standard deviation. If you went to a 95% CI it will be higher than +/- 0.4ppm. I say all this and have the DO600 myself. I find it useful for measuring oxygenation levels post pitch but don't trust it for the key <1ppm readings.

My experience tells me that while the specs say+/-0.4 the meter is actually a lot more accurate then stated. In doing some work with zero O solution as well as a lot of experimenting with yeast DO procedure, you get a nice curve on the plotted data as opposed to more scattered points you would expect with lower accuracy. Also users of this meter have reported, on other forums, when doing the YDO procedure almost exactly mirrors each others measurements pretty closely.

 

[Iseneye]

My experience tells me that while the specs say+/-0.4 the meter is actually a lot more accurate then stated. In doing some work with zero O solution as well as a lot of experimenting with yeast DO procedure, you get a nice curve on the plotted data as opposed to more scattered points you would expect with lower accuracy. Also users of this meter have reported, on other forums, when doing the YDO procedure almost exactly mirrors each others measurements pretty closely.

Cool thanks for that. I wish they would provide proper specs on their website.

 

[mabrungard]

In doing some work with zero O solution as well as a lot of experimenting with yeast DO procedure, you get a nice curve on the plotted data as opposed to more scattered points you would expect with lower accuracy.

How are you monitoring the DO drop? With the type of oxygen measuring probe used in these inexpensive meters, the measurement process consumes oxygen. If you were to leave the probe in a sealed vessel with an oxygen-rich solution, the DO would eventually drop to zero as the probe consumes all O2.

 

[dyqik]

Probably not, but N2 is more "safe" in regards to having large amounts in the air around you.

@rabeb25 This is dangerously wrong. N2 is much more dangerous than CO2 with respect to suffocation. N2 is completely undetectable by the body, and the effect of it increasing past about 85% in the air is for you to drop unconscious with no warning, and no warning signs to others.

CO2, on the other hand, causes hyperventilation and a strong adverse response that gives you time to remove yourself from oxygen depleted area before suffocation.

I've been a safety person for a cryogenic lab using liquid nitrogen, and have to take yearly safety trainings on cryogenic and laboratory gases. There have been several well-publicised cases of scientists and researchers dying in labs due to LN2 leaks, and more than one case where someone who went into the lab to help them also succumbing to suffocation. One very near miss happened in the Cavendish Laboratory when I was doing my PhD there.

 

[rabeb25]

Thanks for the detailed reply rabeb. I went for a run today and had questions popping in my head:

What was your SMB rate in the standard batch and in the BIAB batch? Your meter indicates that more O2 is getting into the BIAB batch (more on that later). My response would be that the BIAB batch requires more SMB to counter that. I've got no idea on how to do the numbers but I have always assumed that BIAB requires a higher dosage rate than underletting. My first batch was 100ppm no sparge and was way too much and could taste it in the finished beer. Second batch I dropped down to 50ppm and I couldn't taste any residual. I have seen on here that ales should be around 30ppm and lagers 50ppm. Throwing random numbers out there for BIAB you may need to go to 50 and 75 or whatever works for the system.

I'm not going to be the annoying guy who says "do a triangle test" but did you have anyone else taste the two batches? I think it is fair to say that you would have expected a difference so are biased (no offence intended). Did you do a blind test on yourself or has anyone else tasted it and come to the same conclusion?

I have commented on it before but IMHO the readings you get from the Extech O2 meter are useless for readings around the 0-1ppm mark. The spec sheet states basic accuracy +/- 0.4ppm. Who knows what basic accuracy means but let's assume it is one standard deviation. If you went to a 95% CI it will be higher than +/- 0.4ppm. I say all this and have the DO600 myself. I find it useful for measuring oxygenation levels post pitch but don't trust it for the key <1ppm readings.

Standard rate in the BIAB is 25ppm, and 0 (yes you read that right) in the normal batches (n2 purge of all vessels, lines, grain and ACTIVE sauergut). We have revised our paper to say that really 30ppm is basically on the verge of too much, and I would rather have less fresh grain flavor than sulfur any day. The only way to know if to measure it along the way.. for instance, my dough in was ~1.6ppm/mg/l but after the entire mash I still had ~10ppm sulfites left, so that goes back to tell me that dough in/fast intrusion is the culprit as even though the sulfites eventually consume the o2 in the mash the damage was already done. That also tells you how fast these reactions can happen.

It's a pretty stark difference when you have both beers on tap. Anyone who has tasted that fresh lingering grain can pick it up a mile away. I have ~500 low oxygen batches under my belt, I can pick up that nuance anywhere. No need to even go though the effort its night and day. I am out to brew the best beer possible, thats my only bias. I don't care the method, I care about the results.

My extech has always been solid. It reads exactly what it should. Hot or cold side.

 

[rabeb25]

How are you monitoring the DO drop? With the type of oxygen measuring probe used in these inexpensive meters, the measurement process consumes oxygen. If you were to leave the probe in a sealed vessel with an oxygen-rich solution, the DO would eventually drop to zero as the probe consumes all O2.

Right there are instructions, but basically I slightly move the probe in the solution.. it will jump around then start to settle, once I get a reading that is steady for about a second or so I take that as my reading. If I leave the probe in the sample it will continue to slowly drop, as you mention.

 

[rabeb25]

@rabeb25 This is dangerously wrong. N2 is much more dangerous than CO2 with respect to suffocation. N2 is completely undetectable by the body, and the effect of it increasing past about 85% in the air is for you to drop unconscious with no warning, and no warning signs to others.

CO2, on the other hand, causes hyperventilation and a strong adverse response that gives you time to remove yourself from oxygen depleted area before suffocation.

I've been a safety person for a cryogenic lab using liquid nitrogen, and have to take yearly safety trainings on cryogenic and laboratory gases. There have been several well-publicised cases of scientists and researchers dying in labs due to LN2 leaks, and more than one case where someone who went into the lab to help them also succumbing to suffocation. One very near miss happened in the Cavendish Laboratory when I was doing my PhD there.

Hence my "quotes".

 

[dyqik]

Hence my "quotes".

It's really not a good idea to rely on people understanding what you mean by "quotes" with safety advice.

 

[bierhaus15]

MillerCoors/New Belgium has a technical paper on sulfur dioxide that is well worth the read for those still LOWDO brewing.

 

[Bilsch]

How are you monitoring the DO drop? With the type of oxygen measuring probe used in these inexpensive meters, the measurement process consumes oxygen. If you were to leave the probe in a sealed vessel with an oxygen-rich solution, the DO would eventually drop to zero as the probe consumes all O2.

Just by direct measurement at various intervals. I see your point but since the volume of these tests were either half liter or 30 liters, consumption by the probe in those volumes was probably negligible. I will say there is definitely more noise in the data when the membrane gets older. Maybe the stated accuracy is an average over the expected life of the membrane. Either way my feeling/experience is this instrument is fairly accurate even sub 1ppm.

 

[cyberbackpacker]

MillerCoors/New Belgium has a technical paper on sulfur dioxide that is well worth the read for those still LOWDO brewing.

Got a link? I couldn't find it in my quick google search.

 

[Bilsch]

Huh.. between rarefied atmospheres and sulfite allergic reactions, it's a wonder there are any of us lodo brewers still around.

 

[friarsmith]

@rabeb25 This is dangerously wrong. N2 is much more dangerous than CO2 with respect to suffocation. N2 is completely undetectable by the body, and the effect of it increasing past about 85% in the air is for you to drop unconscious with no warning, and no warning signs to others.

CO2, on the other hand, causes hyperventilation and a strong adverse response that gives you time to remove yourself from oxygen depleted area before suffocation.

I had 3 active 5 gallon lager fermenters going in a single keezer a few months back (American Lager, German Pils, Czech Pils). While stone cold sober, I got the not-so-bright idea of squeezing in a bunch of cans of beer and seltzer on the floor of the keezer to get them cold for a gathering the next night. My head was in the keezer for about 30 seconds, tops, and the CO2 infusion into my lungs almost caused me to faint, and I don't faint easily. Almost felt like a two minute concussion as I recovered sitting on the garage floor. Next time I'll hold my breath.

 

[Iseneye]

Standard rate in the BIAB is 25ppm, and 0 (yes you read that right) in the normal batches (n2 purge of all vessels, lines, grain and ACTIVE sauergut). We have revised our paper to say that really 30ppm is basically on the verge of too much, and I would rather have less fresh grain flavor than sulfur any day.

Thanks - I joined the lowoxygenbrewing website a few weeks ago and hadn't re-read the notes on dosage on the original article. Just reading it now. I didn't realise the recommended dosage had dropped so far. I do everything that is recommended in the old article - pre-boil, grain conditioning, milling right before mash, mash-cap, stainless steel chiller, ferment in kegs, spunding. I'm not prepared to get away from the simplicity of BIAB so will reduce the SMB dosage down to 30ppm and have to live with that. Using the above processes I got an improvement in my beers so it hasn't been a waste.

 

[Magnus314]

My BIAB mash process hot side is:all stainless, grain milled immediately before mash in, grain poured all at once into the kettle on top of the water and allowed to sink on its own before very light stirring to incorporate and break up dough balls, with the kettle mash tun filled to absolute max and sealed with inset lid as mash cap.

30-40ppm SMB max, less for ales usually.

Cold side I transfer just before yeast is fully dropped out and keg and natural carb, then lager.

It works well, lots of fresh grain flavor.

 

[day_trippr]

Try underletting your mash, you may be pleased how well it works wrt preventing dough balls/dry spots, and it's about the best you can do wrt preventing entrained air short of forced purging...

Cheers!

 

[Iseneye]

Try underletting your mash, you may be pleased how well it works wrt preventing dough balls/dry spots, and it's about the best you can do wrt preventing entrained air short of forced purging...

Cheers!

How would you do that with BIAB - i.e. single vessel?

 

[day_trippr]

Ok, I'll admit to assuming BiaB vessels have drain valves.
If that's not the case, my faux pas.
But if you have a drain valve, load the bag first then pump in the strike water...

Cheers!

 

[schematix]

Ok, I'll admit to assuming BiaB vessels have drain valves.
If that's not the case, my faux pas.
But if you have a drain valve, load the bag first then pump in the strike water...

Cheers!

Whole point of BIAB is single vessel simplicity. Pumping in strike from another vessel would imply 2-vessel.

 

[day_trippr]

Doh! My engrained 3V world strikes
Totally spaced out there, sorry...

 

[Cavpilot2000]

My experience tells me that while the specs say+/-0.4 the meter is actually a lot more accurate then stated. In doing some work with zero O solution as well as a lot of experimenting with yeast DO procedure, you get a nice curve on the plotted data as opposed to more scattered points you would expect with lower accuracy. Also users of this meter have reported, on other forums, when doing the YDO procedure almost exactly mirrors each others measurements pretty closely.

How has the yeast DO process worked out for you? I haven't tried it yet, as early on Bryan suggested he noticed a flavor impact (most likely with a Helles though, so any flavor is going to be detectable in a Helles). I don't mind pre-boiling, but it does take extra time and burns additional propane (I can only get about 2 batches out of a cylinder now where I used to get 3-4).

 

[Bilsch]

You know Bryan and others probably have a much better idea of the differences. I did the initial testing of YDO but mostly on smaller volumes of water just to see what it was capable of. I've only brewed a couple of beers with the process and they were hefeweizens so not really a great vehicle to evaluate flavor nuances between boil DO and yeast DO. I use the boil method because I have the equipment and time. The YDO inspiration was simply an effort to try to help those working with larger volumes of water and or could not chill etc.

 

[masaba]

Can too much SMB cause the beer to be astringent? I made 2 LODO batches and both ended up really astringent. They were both ales and I dosed at a rate of 50 ppm SMB and used a no sparge full volume mash.

I have never experienced astringent in my other beers. The LODO runnings out of the mash tun definitely had the brighter sweeter taste and I had no problems with efficiency, but as I said, the final beer once in the keg ended up being a dumper due to the mouth puckering astringent.

 

[mabrungard]

I have never experienced astringent in my other beers. The LODO runnings out of the mash tun definitely had the brighter sweeter taste and I had no problems with efficiency, but as I said, the final beer once in the keg ended up being a dumper due to the mouth puckering astringent.

If you did not account for the sulfate added by the SMB, that sulfate dose will add a bit of dryness to the beer's finish and that may present itself as being 'astringent'. I've made that mistake.

 

[Big Monk]

If you did not account for the sulfate added by the SMB, that sulfate dose will add a bit of dryness to the beer's finish and that may present itself as being 'astringent'. I've made that mistake.

We've also amended our dosage to 30 ppm in the last revision of our paper:

http://www.********************/low-oxygen-methods/

 

[masaba]

If you did not account for the sulfate added by the SMB, that sulfate dose will add a bit of dryness to the beer's finish and that may present itself as being 'astringent'. I've made that mistake.

I did adjust mineral additions to account for the SMB and started with RO water, so I don't think that was the problem although I will go back and check. I will add that each time I used the yeast scavenging method of de-oxygenation the wort.

 

[masaba]

We've also amended our dosage to 30 ppm in the last revision of our paper:

http://www.********************/low-oxygen-methods/

Is that the recommended dose for full volume mashing or do you think I could get away with something less? I really don't want to have another dumped and would like to give this method of brewing a fair shot.

 

[Big Monk]

Is that the recommended dose for full volume mashing or do you think I could get away with something less? I really don't want to have another dumped and would like to give this method of brewing a fair shot.

That's the recommendation for full volume mashing. Just to get a feel for what you are doing, what other mods have you implemeted? Reduced aeration and splashing at dough-in? Underletting? Mash cap?

 

[masaba]

That's the recommendation for full volume mashing. Just to get a feel for what you are doing, what other mods have you implemeted? Reduced aeration and splashing at dough-in? Underletting? Mash cap?

I bought a pump and clamp down everything during transfer. I underlet my dough in. I don't have a mash cap, but my full volume mash essentially maxes out my mash tun (I have the 10 gallon SS mash tun). I have tried to minimize agitation at dough in by underletting, but have found that I need to give it a decent stir to make the temps uniform. I also have all stainless equipment in my process.

 

[Big Monk]

I bought a pump and clamp down everything during transfer. I underlet my dough in. I don't have a mash cap, but my full volume mash essentially maxes out my mash tun (I have the 10 gallon SS mash tun). I have tried to minimize agitation at dough in by underletting, but have found that I need to give it a decent stir to make the temps uniform. I also have all stainless equipment in my process.

If you add a mash cap with a recirc manifold, I would say that you could go down to 20 ppm.