The State of Low Oxygen Brewing: On Progress, Updates and Review


“Every day you may make progress. Every step may be fruitful. Yet there will stretch out before you an ever-lengthening, ever-ascending, ever-improving path. You know you will never get to the end of the journey. But this, so far from discouraging, only adds to the joy and glory of the climb.”

Winston Churchill

Introduction


It has been a little over 8 months since we launched the site. At the time we put the initial content together, we were overflowing with new information. The main drive for putting the site together was streamlining the delivery of the information and to document these great strides forward. At the time we didn’t think there was much of a story left to tell. Boy were we incorrect….

So much has happened since we issued “Methods of the Low Oxygen Brewhouse” that we want to take a step back and review what has changed, what is new, and what is coming down the pike.

 

Recipe Formulation


1.) Color – When we initially started developing the original Low Oxygen spreadsheet, we were assuming 80% of the SRM color calculated using the Morey equation (20% reduction). That value subsequently to 75%, then 70%, and now we are running trials using 65% as a base value. There is no doubt that a color decrease using Low Oxygen methods is expected. Each brewer should keep this information in mind and come up with a number between 65%-80% that fits their needs.

 

Grain Conditioning and Milling


We want to touch upon and clarify some aspects of conditioning and milling. We have seen a lot of folks having issues or actually seeing worse results from conditioning, so we think it needs be discussed in a little more detail. We have found that people with 3 roller mills, and who use slower milling speeds, can completely forgo traditional conditioning methods. The crush you can get from this setup is fantastic. People with 2 roller mills should probably slow down their milling speed, and we have a method in the paper to determine and set your mill speed. Slower is better here, leading to much less shredding of the husk, and that is what we are looking for. Ultimately the best course of action is to listen to your mash tun! If you have a stuck sparge or recirculation its too fine, and if you are seeing uncrushed kernels after mashing its not tight enough. If you have slowed down your milling as much as you can and are still having issues, I would then look into conditioning. Again though, pay attention to your mash tun. In lieu of the conditioning methods, a small amount of water sprayed on the malt to help the mill “grip” the kernels is not a bad idea. Something on the order of 0.5-1% water by weight should be sufficient.

 

Mashing


Many people were having issues with efficiency which was falsely attributed to Low Oxygen brewing. In reality it was high gelatinization of malt, lack of stirring (doughballs), and over-use of sulfites (this can lead to an unaccounted for pH drop).

Sulfite Dose – After having many, many data points come in about sulfite dosing, it seems that, with reasonable assurance, we can specify 30 ppm as the maximum dose. This is especially true if you have implemented means for mechanically restricting points of ingress, i.e. mash cap, gentle stirring and transfer, flow control on pumps, tightening hose and fittings, etc. Limiting your sulfite dose also limits your Sulfate content, which in this environment has shown itself with issues concerning “sulfur” nose and flavor in finished beer. Ultimately testing strips and testing of your system will be needed, PLEASE don’t forgo this step, don’t ruin a batch! With what we know about consumption (represented in the paper), there is no need to overdose sulfites in the wort. Aim for zero sulfites remaining post-boil.

Supplemental BrewTan B/Gallotannins – This is an important concept for those using Antioxin SBT. As you lower the overall dose of Antioxin SBT, you lower the fixed dose of gallotannins, in this case 10%, contained in the overall mixture. For those using a custom “Trifecta” blend, this is not an issue, i.e. as you lower sulfites you can up the BTB/Gallotannin dose to compensate. For those using Antioxin SBT, it is recommended that as you lower the overall dose to get into the 20-30 ppm KMeta range, that you add a portion of BTB separately.

Stirring – YOU NEED TO STIR! Don’t pull out the whisk and whip up some whipped cream, but make sure you have stirred your mash. You want all the grist and water mixed well.

Hochkurz Step – If you choose to step mash, there are some things to consider. The recent malt crops all seem to exhibit some of the same high gelatinization temps, and you need to employ a mash schedule that can handle that. Your mash should always be based around the malt, not the beer. A recent Brauwelt article describes this perfectly. A multi-step beta rest approach is a great technique. However if you don’t want to employ that, you will need to start out at a higher beta temp. I would start at 147 °F, and go from there. When you specifically target certain enzymes you really have to know what you are looking for.

Mash pH – We specifically stated 5.2 in the paper, along with numerous reasons as to why. I think its time to revisit it here. We are going to say that a pH range between 5.2 and 5.4 is what you want. We find ourselves playing with a little higher mash pH to allow for a later boil sauergut addition. The higher ph (5.4) also allows for faster and better enzymatic activity. Also DMS is removed faster at 5.4 pH.

Biological Acidification (sauergut) – Now even more than ever, we strongly suggest and promote the use of sauergut. Being the first we know of that started using it, we have found the benefits of it to be numerous. Be sure to check our blog post here on the making and upkeep of live biological acid. Biological acidification is pretty easy to do, not only as a great way to control mash pH, but a flavor enhancement, and an ACTIVE DO scavenger (only if the culture is live and active, i.e. not refrigerated or frozen). Our trials have showed its great power as an oxygen reducing agent, a low dough in temp is needed though, so the cultures stay alive. We have found great success with a dough in of 131 for about 10 minutes in conjunction with a tight system, will allow you to not have to use any sulfites.

Cloudy Run-off – Cloudy run-off of wort should be avoided at all times. Cloudy trub contain’s up to 40 times more staling fats and lipids than clear run off! This is nothing new for people with recirculating systems, but for those who don’t keep an eye out and try to get as clear as possible.

 

Boiling 


Some people have reduced boil vigor so much that DMS presents itself. A higher boil pH (5.4) will remove DMS ~50% faster than a starting boil pH of 5.2pH so that is something worth looking into.

Use properly stored hops as much as possible. Oxidized hops are another source of fatty acids.

Hot break must be removed – Hot break has the highest amount of lipids and fatty acid in the brewing process. While its true that break has good nutrients for yeast, if your yeast does not consume them they are left with the beer and ultimately make their way into the serving container and will prematurely stale the beer. Some form of whirlpool is recommended.

If using the higher mashing pH, a 10 minute remaining addition of acid targeting 5.1 pH will help with break formation, along with a kettle clarifier.

 

Future


We are still tirelessly pushing the envelope when is comes to not only Low Oxygen brewing practices, but also general brewing techniques. Packaging is still a nightmare, and we are slowly making strides there to ensure freshness. Playing with canning has to be the new favorite fun thing to test. We are testing new kettle clarifiers, colloidal stability aids, and much more! So be on the lookout, we have so much left to test.

We would be remiss if we didn’t thank the huge amount of folks out there testing this since we brought it to you. You brought forth so many new insights and data points. So thank you all!

This paper was always meant to be a living document, as there is just too much evolving in this process to remain static. We have always been updating it as we went, but we finally had enough revisions that it deserved some attention so folks could always get the most up to date information, and keep making the best beer humanly possible!

So don’t forget to update your copies, and check back often to always get the latest and most up to date information out there!

“Methods of a Low Oxygen Brewhouse”