Rapper Snoop Dogg found a novel way to launch his new album this spring: with a star-studded release party in Hollywood that doubled as a showcase for a new fruit-flavored malt beverage called Blast. Conceived by the makers of Colt 45, Blast is the first serious competitor to Four Loko, the notorious high-caffeine, high-alcohol concoction that was banned following a frantic nationwide scandal last fall. Like its controversial predecessor, Snoop’s favorite new refreshment looks as innocuous as soda in its neon-bright supersize cans—but the bubblegum-sweet liquid inside packs a whopping 12% alcohol punch.

To promote the new beverage, the rapper hosted Blast parties across southern California and appeared in a video with a trio of bodacious costars, generating plenty of viral buzz for the drink. But he also inspired a bubbling backlash. “They are trying to blast the minds of our young people,” fumed hip-hop activist Paul Scott, the so-called “Truth Minista,” echoing charges levied last year against Four Loko. Today, the attorney generals of 20 states called for a ban on the new beverage, marketed by Pabst. Critics say that this billion-dollar niche product—one of what the industry refers to as Progressive Adult Beverages, or P.A.B.s—not only targets underage drinkers with its colorful packaging but is also built for binge drinking, with its combustible combination of sugar, alcohol and, until recently, caffeine. The alcohol companies have their own name for P.A.B.s: alcopops. A single can of the original Four Loko contained the equivalent of two Red Bulls and four beers.

Blast’s sensational debut suggests that, with or without caffeine, these convenience-store potables are still fighting it out for the addled minds and pumped stomachs of America's youth. But before the political and media firestorm that erupted last fall, Phusion Projects—the young company behind Four Loko that was started by three former college buddies—was alone at the top...