Partial mash: mash temp too high - what to do?

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kcpup

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I was brewing this morning. I had my strike water at right temp, put in grain bag, pot lid, and set my timer like normal.

Timer went off. Iodine test showed non-conversion. I checked temp and it had dropped a bit low (mid 140's), so I turned on the heat. I was having trouble getting temp back up (I thought), so left heat on for a few minutes and turned off. [I have an instant read thermometer.]

15 minutes later (now we're at one hour), still no conversion. That's never happened yet.. Water temp still wasn't in the 150's, so I turned the heat on again for a few minutes and turned off.

15 minutes later still failed iodine test. I decided to stir the grains. When I did and retook temperature, it was almost 180 degrees! I was a bit freaked out...

If I remember, this too high temp has "shut down" the starches and they will no longer convert. I tasted the wort and it does have sweetness, so I think they partially converted.

Advice on what to do next? I haven't started my boil yet. I'm going to finish the batch, that's what ya'll typically say to do. :) But I'm disappointed this happened. :(

Also on guidance on how to avoid this in the future. My hunch is to stir before measuring temperature...


Thanks very much.
 

david_42

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Not all of your grain hit 180F, so it is likely that there is some alpha amylase available. If you have already sparged, I'd let the wort sit for another hour and check conversion.

For the future, buy a bottle of alpha amylase. At 1.25/oz, it's cheap insurance to have around.

And definitely stir, stir, stir, if you have the burner lit.
 
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kcpup

kcpup

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Not all of your grain hit 180F, so it is likely that there is some alpha amylase available. If you have already sparged, I'd let the wort sit for another hour and check conversion.

For the future, buy a bottle of alpha amylase. At 1.25/oz, it's cheap insurance to have around.

And definitely stir, stir, stir, if you have the burner lit.
david_42, thanks for the help. Unfortunately, still failing iodine test.

Where do I purchase the alpha amylase? I googled it and didn't see a specific source. Is it sold under a particular brand name, etc? Where can I find data on how to use? Sorry for all the questions, but thanks for your help!
 

ChshreCat

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JLem

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What grains did you mash and in what proportions?

If I remember, this too high temp has "shut down" the starches and they will no longer convert.
Just FYI - it's not the starches that "shut down", but the amylase.
 
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