For me, one of the joys of traveling is trying new and different foods. I really believe that there is a correlation between somebody's passion to try new foods and their passion as a person. So when I'm asked to eat "smelt" or mopane worms, I try to keep an open mind and ignore the fact that one is rotten butter and the other is an African caterpillar, and just enjoy the moment.
When Sigurdur-the-Viking asked me to indulge in an Icelandic tradition of eating "Viking candy," I was, of course, anxious to give it a try. Then I realize that the "candy" is actually rotten shark. Ignoring the horrific smell, I took a chunk about the size of my thumb and swallowed it. Before I could even process the taste, he said "Oh no, no...you've got to chew on it!" with a mischievious grin.
Channeling my inner Viking, I took an even larger piece and chewed on it. Now, I'm no food critic, but imagine eating the contents of a bait box left out in the sun for days. That's what it tasted like.
Normally, I would be polite, not wanting to offend local sensibilities. But I looked him straight in the eyes and said "this is THE worst food I've ever tried." I was trying hard to suppress my gag reflex. Perhaps my willingness to eat fermenting "organic material" extends only so far as grapes into wine.