It’s worth noting, though, that the taste receptors in testicles aren’t necessarily expressed on the skin of the testicles—as far as we know, they’re located inside, where the sperm are being produced. And even if the receptors do end up on the surface, dipping your giblets in soy sauce wouldn’t enable you to taste them because there aren’t cranial nerves connected to your balls. You lack the proper brain-testicle connection to actually taste things. That said, your brain is a powerful organ and you could probably convince yourself that you were tasting soy sauce by sheer suggestion (or interpret the smell, a heavy component of taste, as you “tasting” it). So carry on if you like—just don’t serve up the leftovers to anyone else.