Extreme aversion to certain foods

[Owledge]

Do eastern sciences help answering the question why to some people, certain foods create a very negative reaction (strong rejection)? Connected to psychological trauma, or is there a physiological or some other kind of explanation?

 

Examples:

I absolutely cannot eat fresh tomatoes. Even the smell makes my stomach heave. Processed usually no problem. In tomato soup for example, like on pizza. To a somewhat lesser degree, but still severe the same applies to cucumber.

And I've read on the WWW about someone who feels the same way about all kinds of nuts that I feel about tomatoes.

 

Further curiosities and clues that make the phenomenon of taste so interesting to me:

- At a BBQ party someone brought self-made beer, and he said he made several batches and that the one didn't go well. People tasted it and they all shuddered in disgust. I tried it and it tasted like normal beer.

- I once made a 'healthy mix drink' in a blender, including linseed and wheat germ. I tried linseeds and found they taste strongly like peas. I also tried wheat germ and it was alright, although not pleasant. Well, the drink I made - even its smell made me almost puke - very much like with the tomatoes. I really tried drinking it, but the best I could do was to close my nose and take a little sip from a spoon. My mother though had no problem at all drinking it, but even liked it.

- I've read many times that ayahuasca brew is horribly bitter. People tend to say it's the most horrible thing they ever tasted, and that might cause premature vomiting. I tried it recently and it had a very 'brewy' taste like in beer or other fermented stuff, but not really actively unpleasant. Not the slightest feeling of disgust.

 

So where are these extreme differences in taste coming from?