German Brewing

That's a nice looking cap Nate !
The diffuser is a great idea.

Who is going to run the test with their mash cap and DO meter ?

Experiments:
DO absorbed without mash cap
DO absorbed with mash cap - tight fit
DO absorbed with mash cap - loose fit (X cm from edge)

I was looking at heavy duty aluminum foil (2 layers) covering a foam board for mine. But if not needed...

Since every batch of beer is precious to its brewer.. chances are if one has already made a mash cap, it won't get left off for the sake of a DO experiment. Sadly your probably on your own to do the experiment.

I don't have a do meter, so I can't. But couldn't this experiment be done with just water and smb? It probably wouldn't be perfectly inline with a mash, but the losses should be about the same. Right?

Probably not since their are other antioxidants in the mash besides the added smb. My attitude is the mashcap is relatively easy and cheap to make/procure so why not just do it.

Depends on way too many variables, e.g. Kettle shape, mashing time, recirc or not, how much you stir, how much said stirring or recirculation disturbs the liquid surface, etc. Each of these things could change the DO ingress of an uncapped mash by a factor of 2-3 or more.

A floating mash cap is such a simple, easy, and cheap modification which will cut down the diffusion rate of oxygen into the mash by 95% or more. That's putting the surface area to volume ratio of a 5 gallon homebrew system in line with a pro 1000 hl system. There is absolutely no reason not to use one, because it allows you to significantly reduce your SMB dose without any anxiety and costs no more than a couple dollars.

I think you need more than a DO meter to test this. One might have some success with an optical Do meter, but these are in 5 figures. One could measure the sulfites used up -- which is what Narziss did.

For what it's worth, in our humble world of brewing amateurs an experiment like this would be very interesting, but beyond our scope and lof imited benefit. For what it's worth, the insurance is so easy to implement that it is not worth the expense.

If someone would step up though, then that'll be mighty interesting!

Best

Ghetto system, thought of using the sterile siphon cane from the pump hole in the 10 liter Speidel up through a styrofoam cap and down through another cap in the fermentation bucket. The tip of the cane is sealed with a rubber thing that us used for airlocks.

Looks like crap, but might be a tight system, avoids dripping, and overcomes the OG limitations of the Speidel.



Sent from my iPhone using Tapatalk

And, I'll be using a mash agitator made with a hand drill and a trivet from Ikea, slightly bent. This should improve efficiency and circulation.
https://www.amazon.com/Schroeder-Hand-D ... 441&sr=1-1
http://m.ikea.com/us/en/catalog/products/art/30111087/