mold in petri dish

Moldy food — to eat or not to eat?

Food scientist explains the differences between safe and toxic mold in a food blog interview 

July 24, 2020

After a story about moldy jam in a LA restaurant went viral, Grub Street interviewed food scientist John Gibbons to learn more about mold contamination in food. Gibbons is an expert on beneficial and detrimental molds. In his interview, he explains basic information about what people should know about mold to make smart choices about their food safety. 


From ‘Everything You Need to Know About Eating Moldy Food’ 

What is mold? 

It’s a microscopic fungi. There are thousands and thousands of species of molds. They produce all these digestive enzymes that break down proteins and sugars and fats, export them out of the cell, those enzymes break down the food, and then the mold absorbs all the nutrients once they’re in a good form for them to metabolize. 

What differentiates a good mold from a toxic one? 

That’s kind of the scary part, because some of them are so closely related that you can’t really tell them apart without looking into their genetics. There’s an organism we study called Aspergillus oryzae. That’s koji. It’s used to make sake and soy sauce. It’s really safe. Its closest related species is called Aspergillus flavus. They look almost identical at the genome level. But Aspergillus flavus produces many of these toxic chemicals. If you looked at them, you may not be able to tell them apart, even if you’ve studied them for years.  

How does mold end up on food? 

Mold spores are incredibly buoyant. There’s an estimate that we inhale 50 to 100 Aspergillus spores per day — they’re everywhere. And they just wait until the conditions are right to start growing. 

When you open your refrigerator and something is a little fuzzy, what do you do? 

Because I study this stuff, and I’ve seen some of the really bad effects of different toxins, I don’t really take chances with it. That being said, fungal-fermented foods are some of my favorite foods — I just don’t trust it happening spontaneously. 

Full article on Grub Stree >>

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