Mondo Knows Facts
Blue cheese veins need air to turn blue
The mould grows green-blue only where oxygen reaches it
Blue cheeses are inoculated with Penicillium roqueforti and then pierced with steel needles so air can travel into the paste. The mould grows along those channels and produces the blue-green colour and peppery flavour. A cheese left unpierced stays white inside even though the culture is present.
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Tags: cheese, mould, penicillium
Blue cheese veins need air to turn blue: the short answers
- Where does this come from, and can I check it?
- The mould grows green-blue only where oxygen reaches it. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a food fact?
- Yes. It sits on the Food shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
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