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Galvanized pipe for fryer filter

Hi, I have heard that galvanized pipe should not be used to handle cooking oil because it creates a poison. Hearing this I did a web search that led me to this discussion. After reading the article it seems that there is risk of heavy metal contamination from cooking foods on galvanized steel. Is this the same for cooking oil, or is there an actual poison or carcinogenic that is produced from the oil and any acid that may be produced? The pipe wouldn't be laced near a flame or in direct contact with the food. I just want to drain cooking oil from a fryer to an oil filter. The oil would be 400F tops, probably much less at the time of filtering.

Thanks,

-Ivan

Oh, and Ted, I really enjoy your writing style, you should put that picture of you on the back of a cover someday.

Ivan Chason
end user - Newark, Delaware
October 15, 2008

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Hi, Ivan. Thanks for the kind words. I have never heard of any kind of special poisonous reaction between galvanized surfaces and cooking oil, but I don't think galvanized pipe should be used for cooking oil because it seems the oil could leach the zinc (and chromate if applicable) from the pipe and expose the next batch of food to them.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
October , 2008

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October 17, 2008

Was interested in the reference to "heavy metal".

While I agree that hot food oil and galvanized pipe shouldn't be mixed, I wonder where the heavy metal comes in?

Zinc is just slightly heavier than steel, and about half the heaviness of lead.

At what point does a metal become a "heavy metal".

It sounds like a pejorative term for an element thats essential for human health?

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK

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Geoff has an obvious passion for the metal that provides his livelihood.

Heavy metal is a term that is commonly used to refer to any of the transition metals on the periodic chart. This would include Zinc.

Oddly enough, the "heavy" bad guy lead is not a transition metal, hence not a heavy metal.

These nomenclature issues have been battled by the experts for years.

Kurt Sammons
- Inman, South Carolina
October 23, 2008