xxdcmast

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Pretty much everyone here at one point or another probably has used iodione mixed with water as a no rinse sanitizer. I know that in the right concentration and wet it will sanitize for you but how? By what method does iodine kill the bad stuff we dont want in our beer? I dont think ive ever read this before.

Yooper

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I'm not a chemist, but I work in a hospital and know that we use iodine often for sanitizing, actually as Betadine.

Take a look at this link from a book called "food sanitizers" for the chemical reasons behind sanitizing with iodine: Principles of Food Sanitation - Google Book Search

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Broken Leg Brewery
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Edcculus

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Here is my basic understanding. Iodine, like chlorine (bleach) is a halogen. Halogens are not very friendly to living cells. Small cells (wild yeast, bacteria etc) are very susceptible to these "poisions".

In a diluted state, Iodine is not harmful to humans. I am very aware of this since I have been a backpacker for many years. When I was young, lightweight water filters were expensive. We used iodine to sanitize drinking water on the trail. Since iodine typically leaves a solution fast, we had to treat the water, then wait a few hours before drinking.

BigEd

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Short and sweet they breach the cell walls of the organisms then denature the proteins and enzymes that make the cell work.

HenryHill

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And while we are discussing the how's of sanitizing, can someone explain how oxyclean and pbw specifically work?

IIRC, one is acid and one is base, but.....

And what's this about one should be used warm and the other cold?

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Edcculus

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The brew strong episode on Cleaning talks about cleaners like PBW, oxyclean etc.

The sanitation episode talks about all sorts of sanitizers and how to use them.

BigEd

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No, they are both alkaline or bases. The common powdered detergents used for homebrew cleaners are all based on various blends of carbonate salts like sodium carbonate, sodium sesquicarbonate, sodium percarbonate, etc. An alkaline solution is created when these cleaners are dissolved in water with lots of negatively charged OH ions. These ions surrond and attach to the acidic organic "dirt" particles bringing them into solution so they can be washed away. Percarbonates contain hydrogen peroxide but only release it when heated, hence Oxyclean and other such products made with percarbonates require hot water to work properly.

mkade

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Realistically anything can sanitize if it will kill bacteria, and this occurs by being highly reactive towards typical bonds and compounds found in biological organisms. Now, that being said, it might not be good for beer if some residue is left behind. Heat sanitizes because heat breaks bonds, probably weaker esters or phosphates before going after amides or carbon-carbon bonds. Strong base will hydrolyze esters to make carboxylates. Iodine is highly reactive (though less so than chlorine or bromine), and can halogenate double bonds, etc. I guess at the end of the day it's just organic chemistry.

HairyDogBrewing

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Speaking of bromine:
Does it have any advantages for homebrewing?
I think it's used in pools, hot tubs, etc. so it should be readily available.
Why not use it for cleaning and/or sanitizing?

EoinMag

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I think you possibly could use bromine as a sanitiser and your wife might even thank you for it when she gets to sleep without you hassling her for a bit of fun now and again.
Bromine used to be added to tea for the british troops on the frontline in WW1 to stop their sex drives and allow them to keep their mind on the war and err off their "weapons".
I'd not want it in my beer.