wasabi
It is sad that most sushi lovers will never have real wasabi. I had assumed that I had sampled real wasabi when I spent several days eating sushi morning noon and night in Actual Japan. But even then, there is a good chance I never tasted the stuff.
The reason that most "wasabi" is fake, and the agronomy and chemistry of wasabi, turn out to be really interesting.
Here is the background info references in the video.
To have an effect, a molecule must bind to a receptor and trigger a signal. Studying a receptor's structure can give us insights about the way this triggering process works.
Capsaicin is a fascinating molecule that puts the "pep" into peppers. Curiously, the amount of capsaicin in a pepper is measured with a test devised in 1912 by Wilbur Scoville. Dried peppers are dissolved in alcohol, this liquid extract is diluted in water, and trained people determine the pepper's Scoville value by "tasting" the heat.
I wonder how these people are recruited. I like hot sauce but I can't imagine…