# Why did the garlic turn blue? **URL:** \ **Category:** Factual Questions\ **Created:** [January 26, 2008, 10:14pm UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129 "2008-01-26T22:14:41Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![carlotta](https://avatars.discourse-cdn.com/v4/letter/c/898d66/32.png) [@carlotta](https://boards.straightdope.com/u/carlotta)\ **Post date:** [January 26, 2008, 10:14pm UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/1 "2008-01-26T22:14:41Z")
I have a crockpot dinner going right now Here are the ingredients chicken breasts, chopped onions, pressed garlic, cinnamon sticks, tumeric, olive oil, chopped dried apricots, honey. When I peered in early in the day, the pressed globs of garlic were an unnatural shade of blue green. Normally I would’ve stirred, but I held off. Now several hours later, they are still blue green, a slightly more cooked shade. Same old crockpot, garlic press, garlic, etc. as I have used on many occasions. anybody know why? ---
**Author:** ![Zjestika](https://avatars.discourse-cdn.com/v4/letter/z/8edcca/32.png) [@Zjestika](https://boards.straightdope.com/u/Zjestika)\ **Post date:** [January 26, 2008, 10:31pm UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/2 "2008-01-26T22:31:43Z")
This happens to me all the time when I make garlic bread. Blue/green garlic. I’ll be interested to hear the why. ---
**Author:** ![Nametag](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nametag/32/406_2.png) [@Nametag](https://boards.straightdope.com/u/Nametag)\ **Post date:** [January 26, 2008, 10:35pm UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/3 "2008-01-26T22:35:57Z")
I’ve found two possible causes. One is that the anthocyanins in garlic can form pyrroles, which are colored; this usually only happens in the presence of acid, but slow heating might do it too, especislly if the garlic is immature. The other is that sulfur-containing compounds in garlic will react with copper in your water or picked up from utensils to form copper sulfate. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [January 26, 2008, 10:36pm UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/4 "2008-01-26T22:36:22Z")
[QUOTE=carlotta] I have a crockpot dinner going right now Here are the ingredients chicken breasts, chopped onions, pressed garlic, cinnamon sticks, tumeric, olive oil, chopped dried apricots, honey. When I peered in early in the day, the pressed globs of garlic were an unnatural shade of blue green. Normally I would’ve stirred, but I held off. Now several hours later, they are still blue green, a slightly more cooked shade. Same old crockpot, garlic press, garlic, etc. as I have used on many occasions. anybody know why? [/QUOTE] Google does :). I read the answer a few years ago, and you inspired me to look it up. [Here it is](http://www.foodnetwork.com/food/ck_culinary_qa/article/0,1971,FOOD_9796_1702231,00.html): > [@](#): > > Acid is the culprit. Garlic contains anthocyanins, water-soluble pigments that turn blue or purple in an acid solution. While this color transformation tends to occur more often with immature garlic, it can differ among cloves within the same head of garlic. > > Acid is the culprit. Garlic contains anthocyanins, water-soluble pigments that turn blue or purple in an acid solution. While this color transformation tends to occur more often with immature garlic, it can differ among cloves within the same head of garlic. Daniel ---
**Author:** ![carlotta](https://avatars.discourse-cdn.com/v4/letter/c/898d66/32.png) [@carlotta](https://boards.straightdope.com/u/carlotta)\ **Post date:** [January 26, 2008, 10:38pm UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/5 "2008-01-26T22:38:49Z")
Oh, you know, I forgot an ingredient, lemon juice, so there’s your acid. Thanks! Safe to eat? ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [January 26, 2008, 10:45pm UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/6 "2008-01-26T22:45:56Z")
I was wondering–I thought maybe the apricots and honey were the acid. Yeah, should be totally safe to eat. (I first saw this, btw, when I made pepper-garlic vinegar. Delicious stuff, but the smurfy garlic was pretty alarming). Daniel ---
**Author:** ![Mrs.Cake](https://avatars.discourse-cdn.com/v4/letter/m/2acd7d/32.png) [@Mrs.Cake](https://boards.straightdope.com/u/Mrs.Cake)\ **Post date:** [January 27, 2008, 12:25am UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/7 "2008-01-27T00:25:07Z")
I just want to say that this sounds delicious. What time is dinner? ---
**Author:** ![Zjestika](https://avatars.discourse-cdn.com/v4/letter/z/8edcca/32.png) [@Zjestika](https://boards.straightdope.com/u/Zjestika)\ **Post date:** [January 27, 2008, 12:49am UTC](https://boards.straightdope.com/t/why-did-the-garlic-turn-blue/435129/8 "2008-01-27T00:49:38Z")
But wait. How does acid explain bluegreen garlic when I make garlic bread using bread, butter, garlic, and a bit of mozzarella? It’s only under the broiler for a few minutes so the slow-cooking thing that **Nametag** posits wouldn’t explain it… or would it?