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Name: Jeff B.
Status: other
Age: 40s
Location: N/A
Country: N/A
Date: 5/24/2004

How cold does it need to be to prevent mold from growing or forming?

I'm not sure I've ever heard what the coldest known example of growth is. It won't be a hard -and-fast number.

Granted, no organism can move enough molecules around if it's frozen. So most things are greatly slowed down at 0C or below. But they aren't all water, and they can have "antifreeze" chemicals in them, so they can do some slow growing and multiplying even several degrees below zero.

At much colder temperatures like liquid nitrogen, not only do things have difficulty moving, but most chemical reactions can't climb over their own little speed-bumps (activation energy).

However, if you have a real example of bread-mold visibly growing in a freezer (and you are sure the freezer works right), it might be worth talking about. Anything which has been in a freezer for a year has had a long time to have some slow growth of some organisms, and plenty of risk that there were occasional warm hours with fast growth, so it would be risky to eat.

Jim Swenson

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