March 27, 2008

Stainless Steel As Odor Remover

Stupid Question ™
Nov. 23, 2000
By John Ruch
© 2000

Q: Cooking stores sell a block of metal you’re supposed to rub on your hands to remove the smell of garlic. How does it work?

A: Simple: it doesn’t work. Except in the sense of providing a market for junk steel.

King of this market is iSi North America’s Odor Steeler, a thing that looks like a stainless steel bar of Dove soap. You use it like soap, too: rub it between your hands under cool running water, and supposedly it removes garlic, onion, fish and nicotine smells.

The poor man’s version is Cedar Fresh’s Onion Off!, which looks like a nickel-plated bar of hotel soap.

Onion Off! Claims to “bind oder-causing oils to water”; Odor Steeler is mum on chemistry. Both companies’ phone numbers are out of service.
Onion Off! also claims to be used by professional chefs. The American Culinary Institute in St. Augustine, Florida said that’s a crock. Real chefs use white vinegar or lemon juice solutions.

In my own experiments with garlic and onion, neither steel product did anything more than just rinsing with water did. (No surprise: my stainless steel garlic press also stinks unless I use soap and a good scrubber.) In both cases, my hands remained smelly.

“Removing garlic and onion odors with a bar of stainless steel sounds like a scam,” said Ohio State University chemistry professor Gideon Fraenkel. “There’s nothing in steel that would react with a component of garlic to remove the odor. If there was, then you couldn’t cook in stainless steel vessels.”

I did find one news story in which a chemist claimed that a reaction known as hydrolysis, in which water ionizes, could be involved. But hydrolysis involving organic compounds in faucet-temperature water is pretty rare. There are odor-killing compounds that work by hydrolysis, but they all feed bacteria that consume offensive substances through hydrolysis—no steel involved.

And stainless steel’s virtue, after all, is that it doesn’t react with much of anything (hence, “stainless”). Its chromium content oxidizes rapidly in air, forming inert “rust” that won’t react anymore. Scratch stainless steel, and more chromium will oxidize, sealing it up again.

The International Iron and Steel Institute—which exists to sell steel—expressed grave doubts about stainless steel killing odors. Spokesperson Ed Price said he’s heard of a similar product for bad breath: a stainless steel tongue scraper. “You get two bottles of mouthwash free with it,” he said. “Enough said.”

These items are cashing in on a small, recent body of folklore about removing garlic odor by touching a stainless steel spoon or knife under running water. “The Garlic Lovers’ Cookbook” began including this lore in its 1987 edition (10 years before Odor Steeler debuted).

An educated guess is that this is a classic case of magical thinking: “Stainless steel is clean, so touching it will make me clean, too.”

In this case, clean of four to twelve bucks.

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