Author Topic: Iostar to measure starch?  (Read 2987 times)

Offline neemox

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Iostar to measure starch?
« on: November 28, 2012, 02:15:57 PM »
Does anyone know if iostar has enough free iodine in it to be used as a test for starch left over in a mash? And, if I find there is still starch in the mash after an hour, check the pH and temp and then let it just keep on going til the starch is gone?

Thanks.

Offline davidgzach

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Re: Iostar to measure starch?
« Reply #1 on: November 28, 2012, 02:30:06 PM »
I'm not sure about Iostar, but if you hit your mash temp and left it for an hour without losing much heat, I would not worry about taking an iodine test.  Go ahead and lauter. 

Dave
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Offline weithman5

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Re: Iostar to measure starch?
« Reply #2 on: November 28, 2012, 02:39:10 PM »
i have never done an iodine test.  from other threads i am not sure it is all that worthwhil
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Offline denny

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Iostar to measure starch?
« Reply #3 on: November 28, 2012, 02:46:44 PM »
I recommend you just forget the starch test entirely.  It's unnecessary unless you REALLY screw up and it's easy enough to do the test wrong and get a false reading. 
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Offline morticaixavier

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Re: Iostar to measure starch?
« Reply #4 on: November 28, 2012, 04:10:42 PM »
I tried using idophor for a starch test, couldn't tell if it was changing or not. But I do know that when I dump strongish idophor down the sink I can see blue stains where starch is adhering to the SS of the sink so it should work in theory.

but +1 to not really needed unless you have concern about incomplete conversion in which case it might be worth while going to the drug store and getting some actuall iodine stuff.
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Offline davidgzach

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Re: Iostar to measure starch?
« Reply #5 on: November 28, 2012, 04:19:25 PM »
i have never done an iodine test.  from other threads i am not sure it is all that worthwhil

I was wondering how others would respond to this.  I have never done an iodine test either. 
Dave Zach

Offline Slowbrew

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Re: Iostar to measure starch?
« Reply #6 on: November 28, 2012, 04:20:10 PM »
I read, somewhere, that if ythe liquid on top is clear after 60 minutes your mash is converted.  For the most part.  I have never done an iodine test but it seems to work for me. 

YMMV and I may be completely whacked on this.

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Re: Iostar to measure starch?
« Reply #7 on: November 29, 2012, 06:23:58 AM »
Old guy on the Moonshiners show last night stuck his finger in the mash and held it up in the wind. He said if it's not sticky when it dries, it's ready.
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Offline denny

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Re: Iostar to measure starch?
« Reply #8 on: November 29, 2012, 10:21:13 AM »
Old guy on the Moonshiners show last night stuck his finger in the mash and held it up in the wind. He said if it's not sticky when it dries, it's ready.

I'd think it should be sticky from the sugars.  Seems like if it's not sticky it hasn't converted.
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Offline davidgzach

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Re: Iostar to measure starch?
« Reply #9 on: November 29, 2012, 11:52:03 AM »
Old guy on the Moonshiners show last night stuck his finger in the mash and held it up in the wind. He said if it's not sticky when it dries, it's ready.

I'd think it should be sticky from the sugars.  Seems like if it's not sticky it hasn't converted.

Who knows where else ol' Jim Tom's finger has been!!!   :P
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Offline Kaiser

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Re: Iostar to measure starch?
« Reply #10 on: November 29, 2012, 01:21:17 PM »
I think iodine tests are useful and brewers should know how to do them correctly to troubleshoot mash conversion issues: http://braukaiser.com/wiki/index.php?title=Iodine_Test

Kai

Offline denny

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Iostar to measure starch?
« Reply #11 on: November 29, 2012, 01:39:06 PM »
I think iodine tests are useful and brewers should know how to do them correctly to troubleshoot mash conversion issues: http://braukaiser.com/wiki/index.php?title=Iodine_Test

Kai

Obviously if you're going to do them you should know how to do them correctly.  Unfortunately I've seen far too may people who don't know how.  And troubleshooting a problem is about the only use I can see for it.  As a regular procedure it just seems pointless.
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Offline davidgzach

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Re: Iostar to measure starch?
« Reply #12 on: November 29, 2012, 01:48:23 PM »
I think iodine tests are useful and brewers should know how to do them correctly to troubleshoot mash conversion issues: http://braukaiser.com/wiki/index.php?title=Iodine_Test

Kai

Kai,

What types of conversion issues have you seen?  Are some more common than others?

Dave
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Offline neemox

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Re: Iostar to measure starch?
« Reply #13 on: November 29, 2012, 06:40:36 PM »
I think iodine tests are useful and brewers should know how to do them correctly to troubleshoot mash conversion issues: http://braukaiser.com/wiki/index.php?title=Iodine_Test

Kai

As always, a perfect explanation from the Kaiser. Thanks!

To others, I am worried about doing this as a test for conversion efficiency, not just because I like adding extra steps to my brew day. I'll pick up some Iodine and do it the right way.

Offline hopfenundmalz

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Re: Iostar to measure starch?
« Reply #14 on: November 29, 2012, 06:57:05 PM »
I think iodine tests are useful and brewers should know how to do them correctly to troubleshoot mash conversion issues: http://braukaiser.com/wiki/index.php?title=Iodine_Test

Kai

I can't speak for Kai. My own experience is that it saved me on a beer with lots of Vienna and Dark Munich as all the base malts. Should have converted after an hour, was starting to clear, but it failed the test - quickly. Let the beer go 30 minutes longer at a higher temp, passed. The beer did very very well in competitions.

I have no problems doing an Iodine test. Just ask the wife to do it.  ;D

Kai,

What types of conversion issues have you seen?  Are some more common than others?

Dave
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