cooked potatoes turn black in fridge. are they safe to eat?

Another one of those weird food it just ugly or also unsafe. Added some cooked/steamed potatoes to chicken minestrone. After a few days in the fridge, the chunks of potato turned black (not totally, but many on the edges, which were not totally submerged in the soup.
At first I was going to eat them, then was unsure.
Have ditched the potatoes.
But wonder what caused the color change? Was it simply oxidation? Other? Have the potatoes made the soup unsafe?
(For context, I recook or rotate foods to the freezer if they can't get eaten up in safe time limits.)

  • Posted by: Nancy
  • February 25, 2019


Nancy February 27, 2019
OK, searched & found some answers at an Dr Potato (an answer source from Idaho Potato Commission).
Potatoes can turn black from oxidation, black spots below the skin, storage after insufficient cooking.
Black spots should be pared & discarded, not eaten.
In my case, I will discard the leftover soup, as it sat for a few days with the blackened potatoes.
marianne February 27, 2019
Probably a wise choice. I didn’t know that could happen. But I was thinking ‘I’d toss it’ and then you said it!
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