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Old 05-10-2009, 11:27 PM   #1
pnj
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They say the first step is admitting you have a problem.

I can admit it, I'm a dummy.

I am using Idophor and testing my water that has had the grains soaking. The Idophor doesn't change color at all..

Am I using the wrong thing?

I did this test after the grain soaked for 30 minutes and I also tried it two days ago after the grains had soaked for over an hour at 150 degrees.

 
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Old 05-10-2009, 11:34 PM   #2
HairyDogBrewing
 
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Try testing right away, before the starches are converted to sugar.
Iodine will turn black when starch is present.
It will stay brown if all the starch has been converted.

 
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Old 05-10-2009, 11:43 PM   #3
pnj
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That's what I thought. so it made sense the other night when I tested after an hour of soaking the grains. but tonight I tested it after 30 minutes and got the same results. I figured it would take an hour or more to convert the starch...

 
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Old 05-10-2009, 11:48 PM   #4
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Quote:
Originally Posted by pnj View Post
That's what I thought. so it made sense the other night when I tested after an hour of soaking the grains. but tonight I tested it after 30 minutes and got the same results. I figured it would take an hour or more to convert the starch...
No, you can actually have conversion very quickly. I've never tested before 40 minutes, but I've always had conversion when I've tested then.

To make sure, you can always test right at the very beginning of the mash, so you can see it turn black. Then, test it 40 minutes later, to see the difference. You only need a drop of iodine. I use a white saucer to put the wort on, and then dip a toothpick in the iodine and then dab it onto the saucer and drag it around a bit.
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Old 05-11-2009, 12:41 AM   #5
pnj
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eh, as I stated earlier, I'm a dummy.

I thought it would turn black instantly. It did eventually turn black...

 
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Old 05-11-2009, 12:44 AM   #6
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Quote:
Originally Posted by pnj View Post
eh, as I stated earlier, I'm a dummy.

I thought it would turn black instantly. It did eventually turn black...
It turns pretty quick, if there is starch present. Like in 3 seconds. Make sure there aren't any grains touching the iodine.
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