As someone who's sense of taste (in the food sense) is considered strange by others I'd thought I might start a discussion on the topic.
I often get foodstuffs that are 'contaminated' by something that I don't like. A bag of ready salted crisps (I will only eat this flavour or unsalted) for example I often find has the taste of onion (which I absolutely abhor) or other flavour.
I like watercress. But I don't want it to be contaminated with the flavour of onion. I sometimes buy a bag from the supermarket (one supermarket seems to be more at fault with this than others) and suddenly without warning I can taste onion. And then I cannot eat anymore, on one occasion it was several months before I could eat it again. And sometimes I can taste the bag it's in.
Bread is another one. I like bread good and plain. No fancy flavours in it. Brown, white or granary freshly baked with a spread of butter - mmmmm! But sometimes the baker has not cleaned out the machinery properly and I can taste onion or tomato in it. Then I cannot eat it further, it has to be thrown away. I usually bake my own bread with a breadmaker which prevents this but sometimes I need to buy a loaf.
Fish and chips - sometimes once again the 'onion' gets into it when bought from the take away.
I am often told my food habits are too fussy. I have been told it must be my imagination as 'if you can't see it or smell it you won't taste it'. What rubbish! I have very simple needs, it doesn't ;matter whether I have the same food day after day or not. Very easy to satisfy - no messing about needed, just bread and butter and a bit of cheese, watercress, or ham or jam or honey and I'm happy. Add to that list bananas,most jelly, yoghurt, boiled or poached egg, baked potato (with butter and salt, nothing else) and fish and chips, and some fresh or tinned fruit and that is about the limit of my dietary intake.
It may not be considered 'healthy' but I've been like this for more than sixty years so I'm not going to change now!