In today’s edition of Everyday Explained, we explore what causes these black spots and whether these onions should be eaten or discarded. You may notice black spots on onions and wonder whether they are dirt or mould. Sometimes, even after you try to scrub them clean, the spots remain. So, what exactly are they? Are the onions safe to clean and use, or could they be dangerous to consume?
So, your hack of chopping the part away won’t work. The US Department of Agriculture’s Food Safety and Inspection Service (USDA) discussed mould on food. They are made up of thread-like structures and produce spores that can travel through air, water, or insects. These spores also give mould its visible colour, which may appear as the black coating you notice on an onion. What appears on the surface may only be one part of the growth. Sometimes, the mould sprouts thin, root-like threads that can go deep into the food and sometimes may be hard to detect with the naked eye. The USDA cautioned that if mould growth is extensive and widespread, it is best to discard the onion instead of trying to scrub it clean and consume it.
Mould grows in warm and humid conditions, so it is best to avoid storing onions in such environments.
As mentioned earlier, mould may penetrate the food even when it is only visible on the surface to you.
