Interesting German Brewing PDF

[TexasWine]

It's not the CO2 that scrubs the O2, it's the yeast that scrub the O2. So you're sort of right in that yes, the natural carbonation is a side effect of transferring during active fermentation. It is done to reduce the O2, and will give you natural carbonation

However, the other point is that canister CO2, even at 99.9% purity, is still too impure to keep below the O2 thresholds that cause staling.

Thus you solve both problems by racking while active, and carbonating naturally.

OK. I see where you’re coming from now. I avoided all biology courses in college, so bear with me on this. I’m still not 100% convinced it’s the yeast consuming the oxygen and not the resultant expelled CO2 scrubbing it out. Here’s why.

Let’s theorize you didn’t transfer the beer and it just sat in the primary until terminal gravity was reached, and consequently no additional oxygen was introduced mid fermentation. Everything would be fine and good, and to reach terminal gravity the yeast would consume a specific amount of oxygen, nothing more and nothing less, and expel alcohol and CO2.

However, in the event that you transfer the beer mid fermentation, if oxygen is present some will be dissolved into the beer in the process. So the question is this; just because more oxygen is now available, will the yeast consume it? In other words, why would the yeast suddenly need more oxygen to chew through the same amount of remaining sugar?

Logically, I would say they don’t. The yeast have a certain amount of work to do in chewing up the available sugar. That work will require a specific amount of oxygen and will produce a corresponding amount of CO2 and alcohol. After all, that’s how we’re able to bottle carbonate without blowing up our bottles. But, as I said, I avoided all biology and have no basis for this other than what seems logical to me.

Last thing. If carbonating with the canister results in more mols of oxygen being exposed to the beer, then I agree it will result in more oxygen going into solution. I can see how forced carbonation carries oxygen with the CO2. What this means, though, is that your beer will inevitably become more and more oxidized as you dispense the beer. The amount of CO2 to dispense a full keg of beer at 12 psig is about 60% of what it takes to carbonate that same beer to 3 volumes.

 

[orangehero]

Yeast will consume some amount of excess oxygen, providing protection from oxidation, without any additional simple food source. If I remember correctly Bamforth even mentions running beer through a yeast bed to reduce oxidation flavor products.

 

[KeyWestBrewing]

One thing of interest is an experiment in the German Brewing forum using dry yeast and DME to deplete oxygen levels in the premash water (8 gallons). The DO levels were comparable to boiling and chilling to mash temps. Which makes sense since Yeast devours oxygen. The O levels were @0.47 ppm after 20 minutes and 0.18 ppm after 15 hours.

13 grams of yeast and 13 grams of DME (he later uses 6 grams Dextrose) were used. The yeast would just die off at high temps and become nutrient, and the sugar increase in minimal. One could do this to save time, then hit it with the SMB to keep O2 from re-entering and Brewtan B to keep the oxidation process to a minimum.

Curiosity got the better of me today and I decided to try this on a malty APA(full vol mash/no sparge) without the Brewtan B as I don't have any. I used a pack of Belle Saison and let it do its thing for ~30 mins while I crushed grain and got things together. Added campden for SMB, waited 5 min, doughed in extra gently.
Break material was chunkier than normal, like bits of tofu, but otherwise everything was the same. Mash was still aromatic smelling like a heavenly mix of Vienna and Fawcett Amber. Sample tasted great but nothing out of the norm. I don't have a side by side to compare the batch to but it'll still be interesting to see if theres a noticeable difference from what Im used to.

 

[techbrau]

If there wasn't an immediately apparent night-and-day difference in the wort flavor as well as a 1-2 SRM decrease in the wort color, then I don't think the oxygen was kept low enough in the mash. The fact that your wort was very aromatic also supports this notion, as low oxygen mashes are significantly less aromatic than normal.

We've only tried the yeast scavenging method with instant bread yeast. I have no idea if 30 minutes is sufficient time for belle saison to scavenge all of the oxygen. There was also considerable variance with the amount of time that it took the yeast to scavenge all of the oxygen in the experiments done. You can read them here:

http://forum.germanbrewing.net/viewtopic.php?t=355

The bottom line is that preboiling is a guaranteed removal of the dissolved oxygen, and I wouldn't do the yeast scavenging method unless I had a DO meter that I could use to verify that the oxygen was indeed gone.

 

[Iseneye]

Yes, you might not have done a low DO mash as Techbrau said. On the only two LODOs I've done so far there has been nearly no aroma at all. I hesitate to say no aroma but that is how it has been. The wort taste should also be very apparent. Super super sweet without the weird bitterish taste if you've tasted it before.

I'm just spit-balling here but apparently yeast absorbs approx 2ppm O2 per hour (source needed ). My tap water has approximately 6-7ppm so with the 30 minute ferment you may still have had 4-5ppm in your mash tun before adding SMB. The SMB dose is supposed to allow for something like 12ppm protection, so some of this is going to be used up by the potential left over 02 in the mash water so at some point in the hot side process you may not have been protected. I'm just regurgitating stuff I've read on the methodology so don't have any proof / knowledge beyond that so take it with a grain of salt.

 

[Magnus314]

If i brew an IPA starting from RO water (basically zeroes across the board), what other salts should I add besides calcium?

 

[KeyWestBrewing]

All fair enough. Like I said I'm just seeing if I notice anything out of the norm. The O2 levels should still be a lot lower from what they'd normally be. I'll grab some bread yeast and mess around some more. Its simple and cheap enough to give a whirl.

 

[Iseneye]

If i brew an IPA starting from RO water (basically zeroes across the board), what other salts should I add besides calcium?

Best answered in another thread. In the brew science forum there is an excellent sticky by aj which should help you out.

 

[jddevinn]

If i brew an IPA starting from RO water (basically zeroes across the board), what other salts should I add besides calcium?

I've simply modified my copy of Brun Water to include the Mash and Sparge Sodium and Sulfate additions from the SMB and proceeded with mineral adjustment like normal.

I know that it is a bit more complicated than this but it's a good start.

 

[Magnus314]

Best answered in another thread.

Not at all.

My IPAs were already great before I ever read this thread. Now I'm told there's a whole other level of so-amazing flavor that I might just dump all my previous batches, even of ales, but no one knows or wants to tell the variance in Sulfates and salts that should be added, even though PLENTY of people on this thread claim they know.

I've read AJ's thread. That's how I knew where to start in the first place.

What should I change from there once I add 50PPM calcium as calcium chloride, and 100PPM SMB?

 

[Iseneye]

Not at all.

My IPAs were already great before I ever read this thread. Now I'm told there's a whole other level of so-amazing flavor that I might just dump all my previous batches, even of ales, but no one knows or wants to tell the variance in Sulfates and salts that should be added, even though PLENTY of people on this thread claim they know.

I've read AJ's thread. That's how I knew where to start in the first place.

What should I change from there once I add 50PPM calcium as calcium chloride, and 100PPM SMB?

Have you done water adjustments before? Do you know if you have a certain sulfate level that you like? Sulfate is a personal preference some like it higher around the 300ppm and some like it lower under 100ppm. 100ppm SMB will add a certain amount of sulfate so it is a simple matter of working out the difference between your target sulfate level and the level provided by the SMB. I'm on a slow computer at the moment so can't look up how much this is.

I don't know your history but if you are just getting into water adjustments you will likely notice a bigger improvement from monitoring and adjusting pH levels. The difference between say 100ppm and 200ppm sulfate is not going to have a massive difference on your beer. I'm only basing this on a basic brewing podcast where they dosed beers at five different levels and the group couldn't reliably tell the difference between the middle beers. Take with a grain of salt as per usual.

 

[TheHairyHop]

Have you done water adjustments before? Do you know if you have a certain sulfate level that you like? Sulfate is a personal preference some like it higher around the 300ppm and some like it lower under 100ppm. 100ppm SMB will add a certain amount of sulfate so it is a simple matter of working out the difference between your target sulfate level and the level provided by the SMB. I'm on a slow computer at the moment so can't look up how much this is.

I don't know your history but if you are just getting into water adjustments you will likely notice a bigger improvement from monitoring and adjusting pH levels. The difference between say 100ppm and 200ppm sulfate is not going to have a massive difference on your beer. I'm only basing this on a basic brewing podcast where they dosed beers at five different levels and the group couldn't reliably tell the difference between the middle beers. Take with a grain of salt as per usual.

Off topic, but could you link me the talk about ph being me important than salts

 

[ajdelange]

The amount of O2 picked up by your beer is not determined by the carbonation method. It is determined by the concentration of O2 in whatever environment your beer is in. In this case, how much O2 is in your CO2 canister.

Not so. This is pointed out by the late C. S. Benedict in his chapter in Bamforth's latest book (just out). If one naturally carbonates to 2.5 volumes and serves with bottles CO2 then the total exposure of the beer to O2 from the CO2 source when the keg is half empty is 1/2 the keg volume times the O2 impurity fraction in the bottled gas. If, conversely, one puts beer from the fermenter which is naturally carbonated to say 1 vol under bottled gas and leaves it until the beer is at 2.5 vols it will have taken 1.5 vols from the bottle and, when the keg is half empty, the total exposure to O2 from the bottle will be 2 vols times the O2 fraction or 4 times as much.

He also mentions that carbonation by sparging with less than pure CO2 will give a better result than injection with less than pure CO2 (but cautions that this may result in scrubbing out desirable flavor volatiles as well as O2).

 

[KeyWestBrewing]

100ppm SMB will add a certain amount of sulfate so it is a simple matter of working out the difference between your target sulfate level and the level provided by the SMB.

Isn't the 76ppm sulfite increase about equal to a 4-5g addition of gypsum? Or am I doing something wrong?

 

[schematix]

Isn't the 76ppm sulfite increase about equal to a 4-5g addition of gypsum? Or am I doing something wrong?

First thing you're doing wrong is mixing units. ppm is a concentration, g are a unit of mass.

 

[ParanoidAndroid]

Curiosity got the better of me today and I decided to try this on a malty APA(full vol mash/no sparge) without the Brewtan B as I don't have any. I used a pack of Belle Saison and let it do its thing for ~30 mins while I crushed grain and got things together. Added campden for SMB, waited 5 min, doughed in extra gently.
Break material was chunkier than normal, like bits of tofu, but otherwise everything was the same. Mash was still aromatic smelling like a heavenly mix of Vienna and Fawcett Amber. Sample tasted great but nothing out of the norm. I don't have a side by side to compare the batch to but it'll still be interesting to see if theres a noticeable difference from what Im used to.

Nice. I picked up some regular bakers yeast from the grocery store. That's what the experimenter used. It super cheap at about 75 cents for 9 or so grams. He has brewed 3 batches with that and has subbed dextrose for DME. The dextrose is cheaper and only half the amount is used when compared to DME. He said all have come out great.

Here is his latest results:

"Started with 7.25 gal of water @ 35c with a mineral profile of: 58 Ca, 6.9 Mg, 10.2 Na, 54 SO4, 75 Cl, 36.1 HCO3
Initial DO reading 7 mg/l
Added 10 g dry bread yeast, (Lessafre) and 10 gm DME. (somewhat lower amounts then the initial testing said were optimal)
No bisulfites were added at anytime in this process to keep this experiment purely about the yeast.
24 min - DO 1.31 mg/l
40 min - DO 0.41 mg/l
1 hr - DO 0.27 mg/l
1 hr 40 min - 0.31mg/l"

He used DME here, but has switched to Dextrose as I stated earlier.

I'll try the yeast/dextrose combo for a basic IPA next to see what happens. I'm going to use Brewtan and SMB also. I'm going to have to do some research on the SMB dosage since I BIAB.

The recommendations someone came up with were 1/4 tsp in strike, 1/2 tsp in a slurry @ last 15 of boil, before finings. That's for 5 gallons.

I don't do 5 gallons so I needed a conversion. I weighed a 1/2 tsp of Brewtan several times. They ranged from 1.12 to 1.29 grams, so I went with an average weight of 1.25 grams = 1/2 tsp Brewtan.

 

[KeyWestBrewing]

First thing you're doing wrong is mixing units. ppm is a concentration, g are a unit of mass.

Right but isn't the concentration your getting from the SMS about the same concentration increase in sulfite you'd get from the gypsum I mentioned? Thats what Im getting at. What the additions change in the actual water profile. Admittedly this isn't my strong suit.

I'll try the yeast/dextrose combo for a basic IPA next to see what happens. I'm going to use Brewtan and SMB also. I'm going to have to do some research on the SMB dosage since I BIAB.

The recommendations someone came up with were 1/4 tsp in strike, 1/2 tsp in a slurry @ last 15 of boil, before finings. That's for 5 gallons.

I don't do 5 gallons so I needed a conversion. I weighed a 1/2 tsp of Brewtan several times. They ranged from 1.12 to 1.29 grams, so I went with an average weight of 1.25 grams = 1/2 tsp Brewtan.

Each tab is supposed to have 440mg so 100mg/L is about 7.25 campden tabs for 8gal of mash water if I did the math right. Not sure what your batch sizes are though.

 

[beernutz]

Doesn't the heating of mash water to a strike temp in the 160s reduce the amount of DO from 6-7 to around 4?

 

[ajdelange]

Right but isn't the concentration your getting from the SMS about the same concentration increase in sulfite you'd get from the gypsum I mentioned?

You don't get sulfite form gypsum - you get sulfate. Sulfite you get from metabite. You only get sufate from metabite if it finds something to reduce (e.g. oxygen). For each millimole (atomic - not molecular gaseous) of scavenged oxygen 1 millimole of sulfite is converted to sulfate.

 

[Iseneye]

Off topic, but could you link me the talk about ph being me important than salts

Off topic:

I chose my wording carefully - I don't have a link because it is what I have noticed myself. I had a noticeable increase in beer quality when doing pH adjustments. I have then played around with different levels of CaSO4 in my standard APA and the differences between the different S04 level were not as big as the differences between pH beers. Note my non-adjusted pH beers would have been approximately 5.8-5.9 while my adjusted beers are 5.4-5.5. I full volume mash so my pH adjustments are greater than someone who does traditional method.

These are all subjective and only what I have noticed myself. A simple test would be to have a low sulfate beer and add various levels of a CAS04 solution to your finished beer to see what level you like.

 

[ParanoidAndroid]

Right but isn't the concentration your getting from the SMS about the same concentration increase in sulfite you'd get from the gypsum I mentioned? Thats what Im getting at. What the additions change in the actual water profile. Admittedly this isn't my strong suit.



Each tab is supposed to have 440mg so 100mg/L is about 7.25 campden tabs for 8gal of mash water if I did the math right. Not sure what your batch sizes are though.

I do 3.25 gallon BIAB batches, so 4.50-4.75 gallons of water for the full volume mash. I was getting confused because I saw some recommendations for a mash amount and a sparge amount. I wasn't sure if you just went with the amount of the mash, or if you added the mash and sparge amounts for the full volume mash.

 

[KeyWestBrewing]

You don't get sulfite form gypsum - you get sulfate. Sulfite you get from metabite. You only get sufate from metabite if it finds something to reduce (e.g. oxygen). For each millimole (atomic - not molecular gaseous) of scavenged oxygen 1 millimole of sulfite is converted to sulfate.

Thank you

 

[KeyWestBrewing]

I do 3.25 gallon BIAB batches, so 4.50-4.75 gallons of water for the full volume mash. I was getting confused because I saw some recommendations for a mash amount and a sparge amount. I wasn't sure if you just went with the amount of the mash, or if you added the mash and sparge amounts for the full volume mash.

I went with a full volume mash so I could treat all the water at once and reduce any O2 pickup from sparging.

 

[Bilsch]

Nice. I picked up some regular bakers yeast from the grocery store. That's what the experimenter used. It super cheap at about 75 cents for 9 or so grams. He has brewed 3 batches with that and has subbed dextrose for DME. The dextrose is cheaper and only half the amount is used when compared to DME. He said all have come out great.

Just have to add that these tests were very rudimentary initial explorations and not a proven reliable way of de-oxygenating your mash water. Without a DO meter your really running in the blind trusting a fickle living organism.

 

[brewmeister13]

Just have to add that these tests were very rudimentary initial explorations and not a proven reliable way of de-oxygenating your mash water. Without a DO meter your really running in the blind trusting a fickle living organism.

I trust a fickle living organism every time I brew. The end result is usually beer. Sorry couldn't help myself, but at the same time, if it has worked on multiple batches, why would it not work all of a sudden?

 

[techbrau]

Because it has taken a different amount of time each time, a different yeast strain was used, and possibly at a different temperature as well.

 

[Bilsch]

I trust a fickle living organism every time I brew.

That's a good point however with fermenting you do have means to know if the yeast are working as you planned such as gravity, pH drop and evolution of CO2. Whereas with the scavenging you cant tell without the meter.

I'm not trying to talk you out of doing it, in fact I'd welcome more testers and data points. It's just that with a persons first few LoDO brews your already introducing so many new variables it might be advisable to increase your chances of success by using more trusted DO method your first few times out. End disclaimer.

 

[brewmeister13]

Because it has taken a different amount of time each time, a different yeast strain was used, and possibly at a different temperature as well.

True, but from the numbers I saw on the German forum, it seems that the DO is below the reliable range of the meter anyway after 1-2 hours on all of the tests. Now I'm definitely not an expert on this stuff so I could be wrong, but from what I've seen the DO meter being used isn't very accurate under 1ppm let alone all the way down to .4 and below.

It also comes down to your end goal as well. While there are definitely some German beer fans on this forum a lot of people are applying this information to different styles, myself included. I'm greatly thankful for your hard work and I've vastly changed my cold side process and equipment to help reduce DO, but if my IPA gets slightly oxidized during mash because the yeast didn't quite get the O2 low enough, I'm okay with that too. I'm still doing more to limit O2 than 90% of brewers.

 

[brewmeister13]

That's a good point however with fermenting you do have means to know if the yeast are working as you planned such as gravity, pH drop and evolution of CO2. Whereas with the scavenging you cant tell without the meter.

I'm not trying to talk you out of doing it, in fact I'd welcome more testers and data points. It's just that with a persons first few LoDO brews your already introducing so many new variables it might be advisable to increase your chances of success by using more trusted DO method your first few times out. End disclaimer.

That's very true too and while I imagine most people are working with a least a hydrometer, many don't have a pH meter. I wish I had a DO meter and could help provide you with more data points, but that is a future purchase for me at best right now. Thanks for all your work and sharing your info with us though.

 

[Magnus314]

You don't get sulfite form gypsum - you get sulfate. Sulfite you get from metabite. You only get sufate from metabite if it finds something to reduce (e.g. oxygen). For each millimole (atomic - not molecular gaseous) of scavenged oxygen 1 millimole of sulfite is converted to sulfate.

Exactly this. So if you are making AMAZING IPA's so good you've dumped the unfinished kegs of every one you made before you figured it out, what're your additions to the same distilled/RO you were so specific about in the paper?