Why does cooked garlic turn green

Don't worry; this is perfectly normal and doesn't mean there's something wrong with the garlic. If you prefer white garlic in your recipes or gifts of canned vegetables, you might think there is something wrong with it. The science behind this effect is related to the same things that give garlic its signature odor and taste.

If you're not crazy about the color, there are some things you can try to prevent it. Garlic contains an odorless sulfur compound called alliin.

It also contains an enzyme called alliinase. When a bulb or clove of garlic is in its natural, whole state, the two chemicals have little interaction and the garlic is relatively odorless.

When you cut or crush the garlic, the alliin and alliinase are mixed, creating an organosulphate compound called allicin. This is what gives garlic its pungent odor and distinctive flavor. And that's why garlic gets only stronger the more you chop or crush it. When garlic is combined with an acid such as vinegar , the allicin reacts with amino acids in the garlic to produce rings of carbon-nitrogen called pyrroles.

Pyrroles linked together form polypyrroles, which throw colors. Four pyrroles clustered together create green this is why chlorophyll is green. Three pyrroles linked together creates blue. I've been cooking with garlic for many years, and I experienced this for the first time tonight. I was making a Blue Apron recipe that included a garlic cheese bread.

I drizzled extra virgin olive oil on the cut sides of a small baguette, spread some grated garlic over that, then topped it with shredded lamb chopper cheese which I had never heard of or used before. I put it in the oven to toast, but it was set to bake, not broil, so it never got really browned on top. It looked normal when I took it out of the oven, but a few minutes later it had developed bright green spots.

I thought that must have been some really weird cheese This just happened to me. I'm making fire cider and went to shake my jars this morning. Looked in the bottom and saw blue garlic cloves! First time I've ever seen this.

Been cooking with garlic all my life. Glad it is not spoiled. I chopped up a heap of garlic all bought from the same store to put into a jar so its easier to use, took me over an hour to chop up, when I went to the fridge the next day the whole jar was blue!

This happened to me for the first time when making garlic dill pickles. I thought now this batch will have to be thrown out. Read this story on line and glad to know the batch is not spoiled. Thanks so much. Just cooked a pickled pork with vinegar, water, peppercorns etc and the garlic turned aqua.

So googled and find your site. Thank you so much from Australia. Have cooked with garlic my whole life. Two nights ago making a lemon garlic sauce for an asparagus pasta dish and when I added the lemon the garlic turned a tourqois color.

I was horrified. Picked out as much as I could and prayed no one would become ill. All the time thinking something was wrong with the garlic. That was a first for me. Glad to find out it is not harmful. This happened to me last night! I thought a scrap of paper or something got in and the blue ink tinged it, or a thread off my shirt, or something! I thought something foreign got in but didn't know what! I ate a few stalks but I rinsed them off because I was weirded out.

I'm glad I Googled blue garlic!! From this article a few things could have caused it Boy, today this happened to me! I was cooking some lentils and, suddenly, after one or two minutes of heat, the garlic is there, looking at me with a very fearsome blue color.

I immediately called my mom for advise and she told me that this had happened to her a few months ago!. What are the odds for two events in such a short period of time? Wow, this happened to me this morning, and thank you so much for posting this! Hope to recreate this, as aqua is one of my favorite colors! Have a wonderful day! The sun is out again in San Diego!

The 3 types I canned all turned blue within a few days. I was going to pitch them out but thanks to this article I will keep. Next time I will can sooner and see what happens.

This happened to me last night while making shrimp scampi. Shouldn't be anything unusual there, just some butter, fresh garlic, lemon juice, and shrimp. Must have been lemon juice, but wait, I've made that dish many times in my life! So, why this one time? Must be some other reason like the freshness of either the garlic, lemon, or butter and how it all combined.

Thank you for your article! Very informative news. I searched the internet and read one comment that it could be due to fertilizers and pesticides that have copper. The user was advise to use garlic to reduce High Blood Pressure but to the contrary, it was increasing.

After lab test they found copper in garlic. I think we need further investigations. We used two varieties of garlic, mixed in the same jars together, and they reacted differently.

The fresher garlic elephant garlic from the grocery store became turquoise and the aged garlic smaller, from the garden did not change. My grandmother fried peppers in oil, put them in a canning jar, added a sliced clove or two of garlic and covered all with vinegar. Very often the garlic has turned blue - did it again this year when I fixed the peppers! This is the first time anyone in our family noticed. From my personal experience produces this color If we add private lemon or the fruit acid to garlic and I think t he acids interact with copper or sulfur.

I have never heard or seen anything like this before, I made homemade garlic bread and grated the garlic clove on top of my butter bread, when I took bread out of oven I was shocked to see my bread was a bright greenish looked moldy so after reading these helpful comments I knew I coyld still eat it, but I just couldn't do and I believe I had to much on it, I did take one bite i do believe the sight of it made me not like it.

Crazy I know but they say we eat with our eyes first. I made two jars of apple cider vinegar and garlic with the same garlic and same vinegar, one turned blue and the other stayed white I think it's because of the metal in the lid from the other bottle. It happened to me because I had two heads of garlic but was going on holiday for two weeks so I minced all the garlic in my blender and froze the minced bits. I came back and put the container in the fridge and it started going blue! I had heard of this before, but i just salted them to preserve them.

I think if you are aspiring to get blue garlic, just chop them then freeze and defrost in the fridge. Yes, I have had bright green garlic color change happen. We recently moved to Costa Rica and my supply of dried garlic was running low so I spent quite awhile peeling and chopping up a ton of fresh garlic some of which was the tinted reddish purple which has a great flavor fresh. I popped 2 trays into the dehydrator, switched them every 45 minutes. When I went to rotate them the 3rd time an entire tray had turned bright green, the color of poison so I thought it had gone bad due to new condistion high humidity, and the dehydration process so I threw out all the green tinted.

I didn't think to check the web and since there was long term storage involved could not risk a contaminated food. Might have to try this again and see if I can repeat the results. Interesting, first time I have heard of garlic going green, hope it never happens to me, but if it does I won't be throwing it out now I know.

I was catering my parents 60th wedding anniversary celebration and was totally freaked when I saw my gorgeous cous cous salad with blue flecks, I was frantically busy and didn't think to send someone to look it up - no one else thought to do it either so it got chucked.

Now cross about the waste but relieved, in future if it happens it will be a feature! I am so happy to have found this page. It actually scared me. I had no idea that was possible. I have veggies every day for lunch: Celery strips, Bell Pepper slices, slice of sweet onion, Pepperoncini's, Olives and 3 gloves of Garlic. I usually buy a bag garlic heads.

I then peel them and slice the bigger ones and put them in a jar. I pour White vinegar over them until they are covered. They are White for about a week, then you notice they are changing colors until they become a nice Blue. I keep eating them and I'm still here.

Glad it is safe to eat. I told my flatmate that I used to chop a lot of garlic, then stored them in refrigerator, just for the convenience for cooking for the whole weeks. Then she decided to try it on, but preserve it as garlic-in-oil because we think oil might help the preservation better than chopped garlic alone. This morning, we almost throw everything away because it turned green.

Thanks for the good article! Thanks for this web site and Google search engine! I was panic and intended throw away my bottle of garlic. It's safe to eat! Your Comment..

I soak garlic with apple cider vinegar it turn into some places of garlic turquoise colour. I was confused. After check this site I got better knowledge about garlic chemistry. I like your hub about garlic. I cook garlic with some of my food. I glad that I was eating a lot of garlic.

I need blue in my body because I am allergic to red. I love garlic. It makes me feel good. Thank you for sharing your knowledge. You are fantastic. This happened to me soon after I moved out and started cooking for myself. I had loved experimenting with complicated and new recipes and had had good success. Then this happened and I was shaken!

What had I done, am I poisoning me or anyone else? The garlic wasn't even a complicated step. I think we ate the dish, but I was nervous til I knew there was no food poisoning. On another note, I remember my mom altering her chicken soup recipe once and it tasted cheesy It was so unpleasant, it ended up in the trash.

I may be weird, but I hope to someday accidentally reproduce that accident just to have the cooking chemistry answer! I use lots of garlic never had that problem mine is okra it seem to turn purplish grey when added to my veg soup could it be spices that clashes with okra it stay pretty and green until I add it to soup I guess I just have to play with it and see its so strange. My garlic and shallots turned green last night as I made a lemon butter sauce.

I was cooking them down with lemon juice and wine before adding butter. The introduction of the acid and heat turned them green-blue. Thankfully, after the sauce was mounted with butter, I could just strain them out. I had the same problem.

I had some pickle juice left over from some gerkins and put in some garlic cloves to see what they would do. I'm colourblind and didn't realise that they'd turned blue until my partner started laughing about them as I was cutting them up! I usually use ginger -garlic paste for my dishes. Yesterday, wen the paste got over, I thought of making it fresh.

I kept the leftover in the fridge n by night it turned green!!!! Just the garlic paste n not ginger.. That was the first time it happened to me. N thanks to the article.. Now I can go back n use it without any worry :. This is fascinating! I have cooked with garlic for years and never knew it could turn turquoise. I would love to see it turn this beautiful color especially since it's safe to eat that way.

It could really enhance some foods and it too is my favorite color. Thank you for sharing this amazing information! Turns out that the reactions that create this blue pigment are related to the reactions that create the familiar pungent aroma of garlic and onions. The chemical precursors of these compounds start out safely locked away within individual cells in the plant, but as you cut or grate them, they get exposed to each other, where they end up reacting, with the aid of anzymes.

According to this New York Times article from Harold McGee , under certain conditions, the chemical precursors will "react with each other and with common amino acids to make pyrroeles, clusters of carbon-nitrogen rings. The molecules are perfectly safe to eat. So why does some garlic turn green and others not? It has to do with the garlic's age. Older garlic will build up larger quantities of chemical precursors than fresher garlic, thus both the region in which you buy your garlic and the specific markets in which you are purchasing it can affect how likely it is to form these blue-green compounds.

Since the colored compounds are created from the same chemical precursors as aromatic compounds, your perception that garlic that turns green has a stronger flavor than garlic that stays white is spot on.

Indeed, level of greenness is almost a direct litmus test for how strong your garlic will taste. McGee notes that in some parts of the world, the color is specifically accentuated by cooking the garlic in acid low pH environments are more conducive to the reaction occurring.

So how can you prevent the greenness and resulting strong flavor from occurring if you prefer your garlic milder? Don't add acid at the beginning. Acid can increase the rate of pigment production.