I’ve found it in mangos outside the U.S., fresh off the tree.
Are you me? I feel exactly the same way about cilantro. 
Agree also about mango, and some other tropical fruit (papaya, I think). So I just avoid them all now. Maybe they contain putrescine or similar amino acid. Tastes more like rancid sweat to me, though, not exactly fish.
Hey, I don’t have enough brain today to fully evaluate these, but if you google spermidine or putrescene and mango, a lot of journal essays pop up suggesting that the fruit/plants might be sprayed with these polyamines to aid production, ripening, or as pest control. It’s possible that these very aromatic compounds may contribute to the flavor we are detecting.
Anyone hungry now? 
It’s mango season now, look out for Keitts grown in SoCal. Delicious!
Yes, it must be different types of mangos.
A friend served fresh mango cubes over vanilla ice cream for dessert and it was ambrosia.
Tried it at home later, and the mango sort of ruined it. Yummy ice cream with cubes that
tasted like you were mopping out a dumpster with pine sol.
I also think frozen mangoes taste fishy - couldn’t drink the smoothie I made… fresh mango don’t taste fishy nor do dried mangoes. I love the mango mint Italian Ice my friend back east makes… I am chalking the whole thing to genetics. In Biology class for nursing school we did a test for taste using paper coated with PTC- (phenylthiocarbamide). To those who are major tasters it is extremely BITTER, to non-tasters - it has absolutely NO taste. (I am a major taster).
To me some dried fruits have a fishy taste. Cilantro tastes like scrubbed metal - like someone washed the pot with a brillo pad and didn’t it rinse out. I love Thai food but skip the soups because of Cilantro… So Salsa is not on my list of favorite foods either…
I am in the frozen mango business and we have some complaints for fishy taste mangoes. We have tried to search for a reason but still without knowing the cause. I have read that the ripening process for mangoes the temperature and ethylene have to be very well controlled to avoid problems, one of them off-flavors.
Hope somebody in the chemical side or research side could provide us with more technical support to search for what causes this bad taste that is detected by a certain group of people and make the arrangement and avoid supplying fishy taste mangoes.
The very first time I tasted mangoes was in a “fresh fruit” salad at a motel buffet. The fruit tasted spoiled to me, and I could not eat it. I just thought someone had left out the fruit salad from the refrigerator for too long.
It was only weeks later when I had another opportunity to taste mangoes in a fruit salad that I identified the “rotten” taste with the mangoes.
I do not know why some foods taste different to other people, but to me, mangoes always taste rotten. My grandchildren, however, love mangoes.
Granny322
I can’t decide if “Fishy Mangoes” is the best or the worst porn star name ever.
I’ve never noticed a fishy flavor, but I’ve noticed they can sometime have an odd “bite” to them, almost like spicy. The nearest thing I could think of to compare it to is like when you get a bite of radish that is “spicy”… but not exactly the same as that… i’ll stop now.
I was going to make the joke I always see Fishy Mangoes when she dances at Jiggles but me from the past went and posted something real years ago.
Fishy Mangoes - good band name!
I once had a chef tell me that anything that tastes fishy is going slightly to way more than slightly bad…including fish.
Never heard this anywhere else, but really fresh fish don’t actually taste all that fishy to me so…
I do not like the turpentine scent/taste, which is why I rarely eat mangos. I can’t say I’ve noticed fishyness in fresh or dry mango.
Ataulfo mangos are the business though. I can eat those until the cows come home.
While I never thought to describe it as “fishy,” I have always felt that mangoes you get on the US mainland have a faintly rancid taste. So I know exactly what the OP and others are talking about.
I haven’t noticed the fishy taste in mangoes I’ve had in Indonesia, Egypt (best mangoes ever!), or Hawaii. FTR, cilantro does not taste soapy to me.
YES, of course mangoes can taste fishy - for the same reason that sometimes berries do. it’s the omega 3 (also found in fish)
This thread makes me so happy!
I’ve never liked mangoes at all… they have a “bile” flavor to me, and I wonder if it’s similar to what some are calling “putrid.” But today I thought I’d go ahead and purchase a frozen fruit mix that contains mango (plus peach, pineapple, and banana) for smoothies.
One sip and all I could taste was fishy mangoes!!
I’ve read a good bit about the cilantro-soap experience (which I do not share, thankfully) and how scientists kind of figured out what’s going on there… now I think it’s time to fund some mango-tasting research!
Also thought it was funny that typing “mangoes taste” into my Google search box resulted in “…like fish” popping up!
Too funny!