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Name: Kristine W.
Status: Educator
Age: 30s
Location: N/A
Country: N/A
Date: June 2003

Why did many slices of bread from the same package put in the same kinds of bags on the same day and placed in the same spot grow several different types of mold? The colors range from brown to green to reddish to yellow to white. Can you explain this please?

There are hundreds of different kinds of mold floating around in the air. The surface area of a piece of bread is huge in relation to the size of each mold spore. You could have a different kind of mold land on each. To a mold spore the distance between one piece of bread and another could be like the difference between London and the US. I would be worried if there were not a lot of diversity in the fungi.


There are many species of molds that might grow on bread. One of the most common, black bread mold, has a white or grey mycelium, and sporangia that turn dark. Another common species is orangish. Like most fungi colors can change significantly as the life cycle progresses.

J. Elliott

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