There is addition information on some of these steps below.  Some of the steps above require no additional information.  Towards the bottom of this page are the low-O2 steps and some general thinking on ways to reduce O2 in your brewing.

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Water

This can be a big topic but briefly, I filter my water to remove chlorine.  This can be done with campden tablets and I have also heard that water tapped one day will gas off chlorine by the next day.  For every batch I brew, I use Chicago (Lake Michigan) water which is actually quite good for brewing.  It took me awhile to understand that my source water could be used for any style.  The critical water ion numbers for this water is:

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Calcium 34, Magnesium 12, Sodium 13, Choride 21, Sulfate 27 and Bicarbonate of 138ppm.

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The bicarbonate number is the only one that is high and bicarbonate can make it tricky for a brewer to get their pH in line.  I have learned that about 4ml of lactic acid in my strike water and another 2ml in my sparge water is enough to neutralize the bicarbonate and help me get my pH into the 5.2 to 5.4 zone.  Also, very quickly:  I use calcium chloride and calcium sulfate regularly in my brewing.  With my calcium number being only 34, I can boost that number to around 60ppm (often stated as a good spot for calcium which is good for yeast health and also beer clarity) by using these ingredients.  I typically use about 3 grams total of these ingredients.  Calcium chloride will create a smooth, round and full character in beer while calcium sulfate (gypsum) will create a crisper, drier character.  By using these in combination to the amount of about 3 grams, my calcium number will end up around 60ppm and I can push the water character in the direction of the beer I want to make.  Oktoberfest or Helles?  More chloride.  Pale Ale, Red Ale, Amber Ale or ESB... more sulfate.  Occasionally I will experiment with some percentage of distilled water.  In those cases I'm trying to reduce my 27ppm of sulfate so the styles would be of the 'soft' variety... maybe a helles or something like a Czech Pilsner.  Otherwise, I have made some very nice, delicate lagers with just my local water.   

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Conditioning Grain

This is one of the low-O2 steps and simply involves misting the uncrushed grain with distilled water to the rate of 2% of the weight of the grains to be used (10 lbs of grain equals 2 ounces of water).  Mist the grains and mix.  Allow to sit to 10-15 minutes before milling.  This should reduce dust in the brewhouse but it will also allow for some control of the milling of the grain so that it doesn't shred.  Allowing for a more controlled milling of the grain should also reduce the amount of O2 pickup when the strike water is added.

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The 30-minute boil

This is something I have been doing since the start of 2017 after some other brewers on my main board started doing it.  This concept has some controversy because for a long time 60-minute boils were standard and 90-minute boils were an alternate way to boil.  For recipes where pilsner malt and flaked corn are involved, the idea of the 30-minute boil sounds risky because those ingredients have often been thought to require additional boil time to reduce the possibility of DMS, a funky, corn-like flavor that can become a permanent part of your beer.  I use corn occasionally but I use pilsner malt A LOT and I have not had DMS in my 30-minute boil beers.  The concept is straightforward:  Try to get the same amount of bittering IBUs that you would get in 60 minutes by increasing your bittering addition so that you get the same IBUs in 30 minutes.  Then, follow your normal hop schedule for anything after 30 minutes.  Yes, if you have a beer with a 60-minute, a 45-minute, etc. addition of hops, you might have to make some adjustments or stick to a 60-minute boil.  I have probably made 50+ batches with a 30-minute boil and I'm a big fan of it.  You'll get double the batches out of a propane tank and your brewday just got 30-minutes shorter.

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Low-oxygen considerations

In April of 2016, a group of curious brewers started looking at how oxygen can cause problems in beer.  For many years, the idea of "aeration" was discussed but not in the same detail as this group.  The ideas put together by this group are still evolving and many brewers are looking for ways to properly incorporate these steps in their own brewery.  There is a lot to digest on this topic.  The forum at LOWOXYGENBREWING has been very useful and the brewers there have helped me to make the transition to low (or in my case, lower-) oxygen brewing.  There has been a lot of discussion about how oxidation can rob beer of its deep, malty character and eventually make a beer undrinkable.  The goal is to preserve that fresh malt character for as long as possible by keeping the beer away from sources of oxygen.  The approach involves various equipment, processes and ingredients.

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First comes the preparation of the water.  The low-O2 group suggests boiling the strike water to get rid of O2 and then chill the water back down to pitching temps.  This was one of the first steps where I knew these processes would change my brewday.  What I eventually learned from other brewers was that using regular baking yeast and sugar in your brewing water, you could get the dissolved O2 in the water to just about zero in about 2 hours.  One brewer mentioned his strategy of using 10 grams of yeast and sugar in 7-8 gallons of brewing water.  I typically use 5 gallons for the mash and 3 for the sparge so I drop 6.6 grams of baking yeast and sugar into the mash water 2 hours before I heat it and 3.3 grams into the sparge water.  Once the water is heating I will add my calcium chloride and/or sulfate and I will add my lactic acid.  One of the weapons in low-O2 brewing is the use of a "trifecta mix".  The mix includes sodium metabisulfite, ascorbic acid and brewtan B.  The first two are used to help scavenge oxygen throughout the process.  These additives are there as your "plan B" in case you *DO* introduce O2 into your brewing, they are your backup plan to help get rid of it.  The Brewtan B is a relatively new ingredient that I have been using since 2016.  It is meant to help with oxidation but it is also meant to help with the interaction of wort and any oxidizing metal found in brewing equipment... mainly copper and iron.  It is known as a "chelating" ingredient which you may have to do your own homework on.  I found that my beers became smoother and softer with the use of BTB.  

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The conditioning of the grain is a low-O2 step as is transferring strike water from a kettle to the mash vessel so that there is as little splashing as possible.  Stirring gently but thoroughly is important.  Next comes the MASH CAP.  The idea here is that a mash vessel with the lid on will trap O2 which will eventually invade the wort through 'surface intrusion'.  I fabricated a mash cap from some high-density foam board I found at Home Depot.  I cut it to size and lay it on top of my mash to separate it from the outside air.  I believe it helps to maintain temperatures which is especially nice for people who do not have a direct-fired mash vessel.

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My recirculation and runoff are probably some of the weakest part of my low-O2 process.  I attach a length of tubing to my mash vessel and run the wort off into a measuring cup with the end of the tube submerged under the wort.  I believe that this part of my brewday is where the trifecta mix is really earning it's money because there will be some amount of splashing and exposure.

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During the boil there are considerations about boil rate.  I have to admit that I have not focused on this area much but there is a middle ground where your boil is vigorous enough but not too vigorous.  The boiloff rate (by percentage) is something that can be researched on LOWOXYGENBREWING or anywhere.  I feel like my boils used to be pretty vigorous so I have started to lean towards a more moderate boil rate.  When I chill, I now use a stainless immersion chiller as opposed to a copper chiller.  Copper interacts negatively with wort with regard to oxidation.

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The transfer of wort from kettle to fermenter is one area where the low-O2 brewers agree that it's okay to introduce O2 because the yeast is going to need it.  Allowing the wort to fall and splash into the fermenter is okay but the brewer should introduce the yeast immediately instead of waiting until the end of the transfer.  This way the yeast can begin uptake of the oxygen quickly.

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The regular fermentation schedule can proceed now but this is where some very good stuff comes in.  On brewday I will have a keg clean and sanitized (Oxiclean and Starsan are pushed out of the keg with CO2) and then that keg will be used as a sort of airlock.  Kudos to some pioneering brewers who helped me with this.  It was suggested to use a stainless fermenter with a port as many brewers use.  To get started, I decided to start with a bottling bucket with a spigot to use as my fermenter.  The fermenter is placed in a fridge (set to 62° for ales, 50° for lagers) and the top of the fermenter is fitted with a standard airlock but just the main piece that inserts into the grommet.  Then a piece of tubing is connected to the stem of the airlock and the other end of that tubing has a liquid-out disconnect on it and is connected to the OUT port of the keg.  I drilled a hole in the door of my fridge to account for the tubing running from fermenter to keg.  On the IN port of the keg is a gas QD with tubing running into a bucket of Starsan.  The CO2 from the fermentation will run into the keg and completely purge the keg of O2.  The low-O2 brewers have mentioned that there is enough pure CO2 from fermentation to completely purge 20 kegs.  I really like this way of naturally eliminating (or at least reducing) O2 mixing with my beer.  When the beer is done and ready to be moved to the keg, simply take the tubing connected to the airlock and connect it to the spigot on the fermenter.  Then take the tubing from the IN port (in Starsan) and connect it to the airlock so that when beer is transferred to the keg it's displaced with CO2 from the keg instead of outside air.  I really like this process too as the beer is never exposed to the elements which can help with O2 exposure but also contamination.

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But there's more...

After trying four batches of truly low-O2 beer, I concluded that I needed to "cheat" a little bit while I worked on my process.  Low-O2 brewers embrace a natural method of carbonation... spunding.  This involves sending the beer from fermenter to keg while the beer is still fermenting.  With about .005 of gravity remaining (if your beer will finish at 1.012 then start the spund around 1.017), the beer is transferred to the keg.  A valve is connected to the keg to help regulate the carbonation level and to prevent overcarbing the beer.  Some experienced brewers choose to not even use the valve and simply close up the keg and allow the rest of fermentation to continue while the remaining CO2 created is absorbed by the beer.  This method works very well and creates a very nice head of foam on the beer.  The only issue I had with it was that a good amount of solid material ends up in the keg.  That might be yeast but could also be hop and break material.  I had so much of this material in those four beers I made that all four were very cloudy (in some cases, sludgy!) for the majority of the time the beer was on tap.  The low-O2 brewers are also against any type of fining because the application of a fining agent is almost always going to result in oxidation.  Also, the thinking is that commercially available CO2 that brewers use for dispensing (and often force-carbing) has too much O2 in it to be used in a true low-O2 brewery which is where the spunding comes in... natural carbonation without the risk of added O2 exposure. 

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I need to work on making sure that only wort and yeast end up in my fermenter.  I seem to get about 4 gallons of very clear wort but then the transfer begins to pick up hop schputz and break material which will cause haze downstream.  So the adjustments I made were to allow the beer to fully ferment in the fermenter and have everything settle.  Then I do the closed transfer to the keg and chill it.  Then I prepare a gel solution and use a sanitized 100ml syringe to inject it into the beer under the surface to attempt to keep O2 at a minimum.  Then I force carbonate.  So the low-O2ers would throw three flags on me but I do feel that my beer is better and I will continue to work on my processes.   One thing I have noticed very clearly is that my beer color is getting more and more pale.  Pale gold lagers are more pale than ever.  Amber beers are lighter amber.  Dunkels are more 'dark amber'.  I also notice more intense flavors from things like Vienna and Munich malt and I also notice that hops are more pronounced with these steps... almost to the point where I may need to reduce them a bit.  I will continue to update this section on new low-O2 steps as they become available.

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