Would you eat mouldy bread?

As the weather gets warmer, you might notice your food starting to go bad more quickly. So we’re here to let you know that there’s no such thing as the clean part of mouldy bread.

The fuzzy stuff you see on the surface of mouldy bread is just the flower/tip of the iceberg of the mould. It’s literally the reproductive organs, alike to flowers on plants, called sporangia. These release thousands of spores which spread everywhere.

If you're seeing these, the mould will have been working its way through the food for a day or two before you see any signs on the surface, so you're definitely not seeing the hidden roots called hyphae, which is why you need to throw away the entire slice and the entire loaf.

“As a general rule, a mould colony of 1 cm in diameter on the surface has also penetrated 1 cm deep into the food”, says Dr Hickey of The Food Standards Agency (FSA).

We do eat mould every day, from antibiotics to blue cheese but there are thousands of different types of mould.

Some are probably harmless but some are not so good like Rhizopus stolonifera, the mould commonly found in foods like bread.

Soft cheeses or any cheeses that can be spread or crumbled, are also prime candidates for salmonella and listeriosis microbes, due to their higher water content.

Always throw away slimy fruit and vegetables. And be wary of apples. A toxin called patulin can be found in damaged or mouldy apples, including mouldy apple juice.

It is almost impossible to tell whether mould is harmless or not simply by looking at it, because some of them can produce dangerous mycotoxins which can be lethal. Unlike bacteria, heating it up won't destroy the mycotoxins.

You can’t prevent your food going mouldy, but you can slow the process down. Mould likes warm, damp conditions with plenty to feed on. A clean, dry and well-ventilated kitchen can help keep mould at bay this Spring/Summer.

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Sources:

BBC Food. (n.d.). Is mouldy food safe to eat? Available at: https://www.bbc.co.uk/food/articles/mould. Accessed: 25/05/2024

USDA (2013). Molds on Food: Are They Dangerous? | Food Safety and Inspection Service. www.fsis.usda.gov. Available at: https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/molds-food-are-they-dangerous. Accessed: 25/05/2024