Authorities have ordered a San Francisco brewery to stop producing its line of beers infused with cannabidiol (CBD). Black Hammer Brewing, in the city’s SoMa district, began brewing CBD-infused beer last year. The brewer also includes terpenes commonly found in cannabis in its recipes to add the herb’s distinctive flavors.

So far, Black Hammer has released eight CBD beers. But it’s remaining brews in the series will have to be the last.

Recently the federal Alcohol and Tobacco Tax and Trade Bureau ordered Black Hammer to cease production. But interestingly, it’s not because of the status of cannabis under the Controlled Substances Act. Instead, it’s because of the bureau’s regulations requiring any non-standard beer ingredients to gain prior approval.

The bureau maintains a list of ingredients that it allows in the production of beers. Breweries that wish to brew with other ingredients must first gain approval from the bureau. CBD, terpenes, and hemp are all not yet on that list.

Jim Furman, the owner of Black Hammer, told local media that he had been “approaching it more from a CBD legality standpoint than a formula approval standpoint.”

Brewery Tapped First CBD Keg on 4/20/2017

Black Hammer released its first CBD beer, Toke Back Mountain IPA, last year on April 20. The first brew’s success led to seven more offerings from Black Hammer.

“They’ve been extremely well received,” Furman said. “Our line of CBD beers has been our most popular line.”

Furman noted that his favorite of the bunch is the Hippie Hill imperial IPA, an ale infused with CBD and Tahoe OG terpenes.

“It’s unmistakable. So fresh,” he said. “It’s got the most dialed-in cannabis flavor profile.”

Furman said that in order to start brewing his CBD beers

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