Foaming Mash

[GrowleyMonster]

So, there is always a good bit of foam after I mash in. (BIAB) Is the mashing reaction still going, as long as foam is being produced? Should I continue the mash until it stops? If the starch to sugar conversion isn't making the foam, what is?

I keep forgetting to get iodine at the drug store but I am reasonably certain that mash temps and time have been enough for full conversion. Or...?

 

[doug293cz]

The saccharification reaction (hydrolysis) does not generate gas. Not sure what else might be going on in a mash to generate gas.

I don't typically see a lot of foaming during the mash.

A better test than the iodine test is to monitor the SG of the wort during the mash. This is pretty easy to do if you have a refractometer. After about 45 minutes, check the SG of the wort in the mash, continue the mash and recheck SG every 15 minutes. When the SG is constant between successive measurements, conversion is done. It is necessary to stir the mash well, in order to homogenize the wort, prior to taking the SG samples. And if using a refractometer, take care not to let water evaporate from the small sample, as this will give you an erroneously high SG reading.

Brew on

 

[hotbeer]

You aren't running a burner during your mash and possibly have boiling temps on the bottom and mash temps on top or something? Though I can't really imagine that happening.

I just don't understand the foam. I don't get foam of any sort at mash.

Do you circulate wort with a pump and the wort coming from the pump is getting aerated?

 

[PCABrewing]

You aren't running a burner during your mash and possibly have boiling temps on the bottom and mash temps on top or something? Though I can't really imagine that happening.

I just don't understand the foam. I don't get foam of any sort at mash.

Do you circulate wort with a pump and the wort coming from the pump is getting aerated?

Or splashing during the recirc.
I would expect that high-fat grains like oats will tend to foam more (under aeration or splashing conditions).

 

[PCABrewing]

Could there me more than a residual amount of StarSan somewhere?

 

[GrowleyMonster]

Or splashing during the recirc.
I would expect that high-fat grains like oats will tend to foam more (under aeration or splashing conditions).

I have been using 3 lbs of quick rolled oats in each batch. Foam is most evident while stirring. After a while it stops and doesn't reappear.

 

[DuncB]

I wouldn't worry it's probably air that is in some of the rolled oats coming out.

Try a tablespoon of oats in a cup and pour some boiling or near boiling water on and I expect you'll see some bubbles.
Just brew on.

 

[Sam_92]

Do you use campden tablets to drive off chlorine? I sometimes see bubbles in my strike water from the campden tablet.

 

[DuncB]

@Sam_92
Surely not foam though? I'm not sure that the reaction makes any gas either.

Perhaps the bubbles are from gas between the particles of the campden tablets, although I crush mine before use.

 

[day_trippr]

If not underletting the strike volume I could see air in the grain bubbling up...

Cheers!

 

[marc1]

So, there is always a good bit of foam after I mash in. (BIAB) Is the mashing reaction still going, as long as foam is being produced? Should I continue the mash until it stops? If the starch to sugar conversion isn't making the foam, what is?

I keep forgetting to get iodine at the drug store but I am reasonably certain that mash temps and time have been enough for full conversion. Or...?

Pics?

 

[GrowleyMonster]

Do you use campden tablets to drive off chlorine? I sometimes see bubbles in my strike water from the campden tablet.

Nah never used them.