[marklubi]

Capsaicin itself is boring. Frankly, I think it tastes rather metallic.

Hot sauces that add it to boost their "spiciness" ratings taste awful as a result. The flavor of it stands out, and not in a good way

[thatcat]

Capsaicin is a terpene and probably enhances other terpenes. The metal taste of pure capsaicin is probably from extraction process