German Brewing

Kunze describes 5 basic methods for degassing water in the brewhaus. They include:
- CO2 washing (stripping)
- vacuum
- hydrogen reduction
- thermal (steam) reduction
- fibre membranes

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CO2 stripping is (can be) pretty complicated, but I think there is a lot of potential for us with the vortex-stripping method. Hydrogen requires a catalyst and constant maintenance and monitoring.

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The vacuum method sounds simple, but Kunze claims it must be combined with CO2 washing, so vacuum alone may only be beneficial at our scale for preventing oxygen ingress during storage.

Thermal degassing is probably the simplest, but it seems we must use steam to truly remove all of the oxygen. I think this is where goat comes in handy to polish off removing oxygen after we boil. As well, it may explain why just pre-boiling batches underachieved in results. The membrane system would seem to work for us, it's just a matter of finding a design and building one. He does state that the difference in concentration between the water and CO2 is the driving force to degassing oxygen.

It would be interesting to see if we could simply distill water, and make degassed water. Pressure cookers could easily be adapted for this. It might require some inert gas flushing as the vapor condenses, but can probably by done.

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Anyone have a simple build for a de-gasing tower?

I wonder what the stripping capacity would be of...
Filling a keg with your brewing water then chilling and force carbonating at high pressure. Then one could let the temp rise while venting though a spunding valve set at ever decreasing pressures over time. The steady evolution of CO2 from the solution should take a considerable quantity of O2 with it, maybe all. If one had a direct fire-able keg, such as the ones without rubber moldings, the whole thing could be raised to the strike temperature and pressure fed to the mash tun. Theoretically if one used enough pressure, chilling would not be necessary for the solution of enough CO2 to provide an adequate strip upon depressurization. The process could be automated and repeated as well to improve the removal of O2.
I doubt though this would be practical, time and cost wise, compared to boiling.
The one advantage that I do see, if it worked, would be the ability to prepare the water ahead of brew day since it should be storable for a while under pressure. (as long as there weren't any CO2 eating bacteria in there)
Just tossing it out there for conversation.

What was the deal with abscorbic acid for degassing again? I remember it mentioned that it was tricky and could cause problems?

Yeah, that's it, thanks