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Old 03-31-2012, 09:23 PM   #1
Moonraker
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Planning my first mash tomorrow and I went to the pharmacy to get some iodine so that I could test for remaining starches after conversion. There were two alternatives - tincture of iodine (2% iodine)? and 'decolorized' iodine. Are either of these good?

 
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Old 03-31-2012, 09:29 PM   #2
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I use the tincture and it works great. I bet either would work. Though I've never heard of decolored iodine
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Old 03-31-2012, 09:32 PM   #3
RM-MN
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You'll want tincture of iodine. It needs to be brownish and should stay that way when you test. If it turns black or purple there is still starch to be converted.

 
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Old 03-31-2012, 09:40 PM   #4
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You can also use Iodophore or Betadine, as they produce the same result.

 
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Old 03-31-2012, 09:45 PM   #5
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Quote:
Originally Posted by RM-MN
You'll want tincture of iodine. It needs to be brownish and should stay that way when you test. If it turns black or purple there is still starch to be converted.
As long as the decolored stuff turns black in the presence of starch it would be fine. Just not sure if it does turn black or if that reaction is also decolored. Best bet is to use the tincture to be safe.
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Old 03-31-2012, 09:49 PM   #6
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With the highly modified grains these days you don't really need to do the iodine test. Most of the conversion happens in the first 20 minutes, the rest of the mash is "making tea", extracting colors and flavor.
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Old 03-31-2012, 09:54 PM   #7
Moonraker
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Awesome, thanks guys. I'll grab some tincture.

 
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