In John Steinbeck’s 1945 novel Cannery Row, the main character, Doc, cannot shake the notion of a beer milkshake, an idea introduced to him in jest by a friend.

“The idea… cropped up every time he had a glass of beer. Would it curdle the milk? Would you add sugar?” Steinbeck wrote. “It was like shrimp ice cream. Once the thing got into your head you couldn’t forget it.”

If only Doc were still around today, he might be surprised to find beer drinkers paying a premium for milkshake IPAs, or their increasingly popular, though more controversial cousin, the smoothie beer. Referred to as juice for adults by some, smoothie beers have carved out a space as the latest brewing trend. Whether it will join the ranks of the brut IPA (brewed with champagne) as a flash-in-the-pan gimmick, or find its way into ubiquity is to be determined; however, local adoption has been uneven.

Alvarado Street Brewery’s latest attempts at smoothie beer are the Daiquiri Island Banana, a boozy frozen daiquiri-inspired imperial sour ale clocking in at 8-percent alcohol, and the Tayberry Cream Slush, a smoothie-styled sour just under 6 percent. Both beers get a healthy dose of fruit and include lactose to mimic the thick creaminess of a smoothie.

Wade Caswell, head brewer at the Monterey ASB location, says banana-flavored beer requires a certain adventurousness, but the tayberry cream is one of the brewery’s most popular.

“We always say we brew beer for people, not for us,” Caswell says. “Popularity ebbs and flows, and we go along with whatever people want at the moment.”