glittery purple unicorn blood. Stouts, lagers, ales and IPAs come topped with pickles or rimmed with Cheeto powder, sparkling luminescent to sick-Hulk green. It’s quite the trip — literally.

Lest anyone be in any doubt about the dangers of investing in some of the "disruptive" new industries emerging from the likes of Silicon Valley, the story of blood-testing "unicorn" (a startup ...