Boiled cheese ravioli for 10 minutes. Added sliced yellow squash for the last 3 minutes. Nothing else in the pot but boiling water, not even salt. It looked fine cooking but after I drained everything in the colander, the squash rind stayed yellow but the flesh turned bluish-green on most pieces. Not all pieces though. It tastes the same as usual. enter image description hereThe color is freaky. Why did this happen?

  • 3
    Note that it's definitely possible to get at least a little bit of this color just from cooking in a pan, so it's probably not too specific to any particulars of this question.
    – Cascabel
    Sep 8 '17 at 3:46
  • As the suggested answer will tell, your question needs additional information: what did you cook the ingredienst in (material)? Please add that.
    – user34961
    Sep 8 '17 at 7:33
  • 2
    Do you use iodized salt, and did you salt the pasta water? Iodine reacts to starch and turns blue. Sep 8 '17 at 14:30
  • Please add a photo?
    – Cos Callis
    Sep 8 '17 at 15:54

Probably the same reason why garlic turns blue sometimes when you cook it. http://www.foodsafetysite.com/consumers/faq/?m_knowledgebase_article=14

its a reaction with sulfur + copper which can naturally occur in foods.


It's cucumber mosaic virus. It is still edible, just makes the food look less desirable and therefore not as marketable. Producers try to avoid/prevent it for that reason. But it is still fine and edible.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.