This might just be because I have almost no sense of smell, but ugh I am sick of cutting up what looks like a fine and dandy onion only to bite into it and get that horrible mealy, rancid taste that invades your mouth.
Just tossed a sandwich because of this, onion looked fine. Worst is when you use it in a prepared meal, I’ve tried to soldier through sometimes and gone NAH!
Ugh god I can still taste it.
Weird. This has never happened to me. If an onion is rotten, it is clearly visible to me, it doesn’t require a sense of smell at all. In my experience, if it looks good, it is good.
Now I’m curious. Is it possible I just can’t tell the difference between a good onion, and an invisibly “rotten” one?
I’m with MrSquishy on this one.
Yeah, I’ve never had that issue myself. I’ve gotten rotten onions, absolutely. What’ll happen is that the outside few layers look fine and dandy, but when I cut through, the inner layers are brown, liquidy, and just generally not good eats. If it’s crisp and clean all the way through, it’s fine.
I’m with the others. A rotten onion is a pretty obvious thing.
I don’t know about the rest of you 
but I have no problem seeing when an onion is bad.
Or an egg. 
Maybe you don’t like onions.
I’ve never encountered a bad onion that didn’t look like a bad onion, at least on the inside.
Grude: Try to not refrigerate them.
I also have never had a “bad” onion that wasn’t visually rotten. Maybe grude’s climate?
What kind of onions?
And what is the deal with onions (specifically, yellow onions) lately? I’m a professional cook, and over the last few months it’s like every 50# sack of onions we’ve gotten has been half-rotten. The last couple sacks have been much better, but I still find a few that are rotten in the middle.
32 years in this business, and I’ve never seen it this bad.
I’ve been having this problem too. I’m throwing out half the onions I buy. Super annoying, especially when I need an onion and don’t have one that isn’t rotten.
I’ve made the mistake before of just trying to cut out the center part that is beginning to look a little dodgy. It’s too late at that point: the funk has permeated the outer layers.
I am extremely shocked that no one in this thread has mentioned sour milk. That hits me more often than onions and eggs combined!
Really? I can’t remember the last time I got bad milk, or bad eggs, for that matter. Onions? Happens plenty enough. It’s still fairly rare, but about 5% of the time, I’d guess.
The small yellow ones(AKA cheapest ones) are the culprit, I’ve started buying only the red ones because although more expensive they have never burned me like this.
I did some googling and it seems others have had this issue and I have seen people say it is due to storage.
Thinking on it the commonality for them is dull looking skin, I have to peel four or more layers to find the actual edible layers, and it seems like the rotten funk gets between the layers in that kind of transparent skin and gives it a slight slimey feel. No part of the onion looks rotten or moldy, it seems like the whatever spoiling it gets between the layers and permeates the whole thing. The taste is hideous like rotten moldering gym socks or something and lingers in your mouth!
YES! This is exactly the kind I was posting about, the cheaper small yellow onions you get in bulk. I assume they are not grown locally but imported, I wish they were visibly rotten because at least that way I could tell and not ruin meals or sandwiches.
But, speaking as a professional cook, red onions are not meant for cooking. They’re meant for salads, and garnish*. Red onions should be eaten raw. Yellow/white onions are part of the basis of almost every soup I make, and integral to so many other dishes. So it is incredibly frustrating when 50% of the yellow onions I cut into are rotten in the middle.
Small yellow onions? Oh no. The onions I get commercially are BIG. And fucking rotten clean through. Like I said in a previous post, this has been going on for the last few months, and I have not previously seen this in 32 years in this business. Something was clearly wrong with last year’s onion crop.
*Garnish. heh Have y’all gone into some chain restaurant, and ordered a burger, and all of the veggie ingredients are “on the side”? What’s there? A piece of green leaf lettuce, and a thin slice of red onion (and a slice of tomato, and a couple pickle chips) … Those aren’t there because they’re good on a burger. They’re there because they make the plate look "pretty. IMHO, green leaf lettuce and red onion have no place on a hamburger. A burger should have iceburg lettuce (preferably shredded) and a nice thick slice of yellow or white onion on it.
Start a small garden? Tomatoes, onions, christophene.