Whoa! Blue onions? OK, calling all you chemists...

I have NEVER seen this: fresh white onions and fresh garlic, minced. Put in a clean skillet to saute without oil or butter and they turned pale blue. Yuck! What in the heck would make them do this?
Obviously I am not going to use them.....



Lori T. December 21, 2020
The culprit in your color change was the garlic. It's an enzyme thing, best as anyone can figure out, sensitive to pH, and a reaction with sulphur naturally present in both items. It can also happen when exposed to a high acid environment, so pickling can also cause it to happen. Older garlic is more suceptible to the change, since the enzymes are more broken down with age. It is perfectly safe to eat, just so you know- if it happens again. In some places, blue or greenish garlic is actually considered an epicurean delight and they go to lengths to induce the color change. Red onions and red cabbage also do the same thing- just so you are forewarned. In fact, when you cook red cabbage, you manipulate when you add in fat and vinegar just for that reason. I guess people don't notice it so much with the red onion and cabbage, because they do start off kind of red-purple anyway. But with garlic, well, it is rather disconcerting.
Miss_Karen December 22, 2020
Whew! Good to know they weren't toxic. I have been cooking onions & garlic lin this manner for YEARS & have never seen this. I already have an aversion to blue food, so I ditched them... No Smurf food for me😉 I do very much appreciate the information though!! Thanks.
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