Why do potatoes become green?

[french fries]

I know potatoes turn green with time. But why? And does that mean they're not fit for human consumption? I have those nice fingerlings I bought about 2 weeks ago at the farmer's market, and I stored them in a paper bag so they won't sprout. But they've already turned green! I've kept potatoes much longer than that before without having them turn green - what gives?

Should I eat them anyway?

Thanks!

 

[jock]

The green discoloration comes from cyanide compounds that form in old potatoes. The spuds are safe to eat so long as you peel enough of the skin to remove all the green. That might be tricky with fingerling potatoes though.

 

[french fries]

Darn... they're almost green throughout - so you're saying.. don't eat them?

 

[phatch]

Exposure to light and age, the potato is getting ready to sprout.

The specific toxin is solanine.

 

[jock]

That's right. I just looked it up and the toxin is indeed solanine. However, the green color is actually chlorophyll produced from long exposure to light. Chlorophyll is harmless but it does warn you of the presence of solanine, most of which is present in the skin.

 

[oregonyeti]

From what I've read, the whole potato should be discarded if there are green areas. Not that one potato will make you ill, but, solanine is not just in the green spots.

 

[french fries]

Thanks guys. I did a bit of quick research and found conflicting info - some said you'd need to eat about 10lbs of green potatoes to actually get sick... either way my wife and I ate them all, skin on and all, so we'll see. - seriously though it's been a couple hours and so far so good.

 

[blueicus]

I find that green potatoes have a strange taste and leaves an unpleasant tingling after-sensation on the tongue anyways, not particularly good eats. But if you're trying to save money...

 

[ed buchanan]

If you look closely at potato chips, you will find a lot of green chips. The key is once cooked it wont affect you. Boiled , fried , baked, as long as cooked its ok. If they are all green all over and inside throw out for the sake of eye appeal alone. They are not thet costly.

 

[phatch]

Not true. Solanine doesn't degrade at cooking temperatures. It's fat soluble so it leaches out of chips easily and french fries pretty well. Boiling and baking do not affect it. Microwaving does a little bit.

 

[mezzaluna]

I make sure to remove all the green, then prepare as usual. I've never had problems, nor has anyone who ate them.

Green all the way through? Ditch them. I don't know if they even make good compost.

 

[boar_d_laze]

The two most common reasons potatoes turn green are envy and seasickness.

BDL

 

[luc_h]

Maybe these 2 references will make you change your mind on the safety of solanine:

Potato plant poisoning - green tubers and sprouts: MedlinePlus Medical Encyclopedia

Solanine - Wikipedia, the free encyclopedia

Interesting to know that solanine is an effective pesticide!
Luc H.

 

[oregonyeti]

One potato can cause toxic effects . . . sheesh. I double checked Wikipedia and found the reference for that statement at 764. Solanine and chaconine (WHO Food Additives Series 30)

 

[eastshores]

That which does not kills us... makes us eat more of it

 

[dc sunshine]

BDL, you are a riot What about jealousy? Maybe the potato was the original green eyed monster

Peel off the green till its gone. There's a million or so Irish out there or Irish derivatives (of which I am one) that will tell you the same.

Have never had a prob eating spuds with a tad of green on them. Are they being kept in the dark in a relatively dry environment? I store mine in a cool, dark pantry, in a plastic basket lined with newspaper. Never! in a plastic bag. They seem to do pretty well in there. And if you can buy them unwashed, but they must be dry, all the better. A bit of soil on them helps preserve them, vitamins and all.

 

[oregonyeti]

I love potatoes but not the envious ones :^) Potatoes need envy no other food, unless they are inferior ones.

 

[luc_h]

You got that one right DC. A problem with potatoes these days is they are almost always washed. The potato <feels> lost without soil touching its skin hence stresses the spud more. Result: they do not store or last long and green faster.

Luc H.

 

[french fries]

Too bad, that for the sake of having a vegetable that looks good, we also have a vegetable that we can't store for extended periods. I remember storing potatoes for months when I was a kid. They were, indeed, pretty dirty.

 

[dc sunshine]

When we were living in the cottage on the farm we got all the potatoes we could ever eat from, ummm, next doors?

The soil was lovely, black and coated the spuds well for months at a time.


P.S. Luc - good to see you back