The Evolution of the American Milkshake

“I don’t drink milkshakes that often.” Behind the counter at San Francisco’s Castro Fountain, Brandon Brooks is tall, lean, and dressed in the spotless white outfit of a midcentury soda jerk. He pauses. As he considers what constitutes “often,” Brooks nurses a dense Irish coffee milkshake. “Maybe one a day. Ish. Sometimes I skip a day.” It’s fair to say, in other words, that in any given year, Brooks drinks his weight in milkshakes. Ish. (Editor’s Note: Castro Fountain closed March 2025 but its sister location The Ice Cream Bar is open)

Caroline and Robin Weir note in Ice Creams, Sorbets & Gelati, their nearly four-pound tome on confectionery ices, that it is almost impossible to define a milkshake. Even their own primary rule—that the milk must be full-cream milk—is an educated stance rather than a universal law. These cold, thick beverages are related to older favorites such as eggnog, syllabub, and milk punch. However, legal definitions, industry jargon, and common use shift and elide over time and geography. Bedrock truths at home may not apply beyond the yard, or over the horizon. In more than a century of Americans making milkshakes, three broadly different types of drinks have been called more or less the same thing. Recently, the “freakshake” has joined them, less as a different sort of drink than an exercise in extravagant garnish.

Embalming fluid was considerably more likely to show up in a Gilded Age milkshake than vanilla, chocolate, or strawberry ice creams.

Advertisements for “ice cream milk shakes,” began to appear in America during the 1880s. But, until the 1920s, ice cream versions of milkshakes would remain occasional novelties. Embalming fluid was considerably more likely to show up in a Gilded Age milkshake than vanilla, chocolate, or strawberry ice creams. (More on that in a moment.)

Some shakes, in fact, contained no milk whatsoever. Shakes of the 1880s and ’90s were called that because their ingredients were shaken manually in tumblers and jars, or in patented, hand-cranked mechanical agitators such as James Tufts’ 1884 Lightning Shaker. Prior to World War I, a shake might be made with brandy, gin, or another ardent spirit. “Cocktail” Bill Boothby, for example, described a Rum Shake in his 1891 drinks manual The American Bar-Tender. His recipe comprised ice, a jigger of Jamaica rum, a large spoonful of sugar, and the juice of two limes, all shaken and then strained. Boothby’s Rum Shake makes a better Daiquiri than many served under that name today. His Milk Shake, typical of the era, followed the same process, but swapped out booze and lime juice with “good milk” and syrup.

The effect of shaking cold milk, ice, and syrup in a closed container is transformative. Agitation introduces air to the mixture to give it more body. Milk proteins stabilize the resulting foam. Previously flat milk puffs into a creamy, velvet drink with a voluminous, persistent head. Fans of a Ramos Gin Fizz, batidos, or caffe shakerato, a café specialty of shaken espresso and cold milk, know this effect.

Not everyone approved. “The devil never invented a more powerful engine to ruin a man’s stomach than the deadly milk-shake,” one grim physician inveighed in the Wichita Democrat in 1888. “I will not be surprised, if those cold milk drinks continued in favor, to see men and women falling dead every day in our streets this summer.”

He had a point. Old milkshake recipes specified “good” milk for good reason. Although food labeling laws eventually stopped the worst of dairy skullduggery, American milk from the 1850s to the early 20th century was notoriously sullied and unclean. Before commercial refrigeration, milk turned rank quickly. Small doses of formaldehyde forestalled its decay and lent an agreeable sweetness. Wags called such adulterated milk “embalmed.” Unscrupulous dealers watered down skimmed milk so egregiously that it became almost light blue. Gelatin might restore a fatty mouthfeel, while stirring in plaster or chalk could imitate the Albion countenance of genuine milk. True artisans of fraud might replenish milk’s ivory-hued cream layer by adding slurried calves’ brains. The brains, by all reports, looked convincingly of real cream. Until, that is, the ersatz milk was stirred into hot coffee, whereupon its cerebral “cream” coagulated.

Yet American dairy groups continued to promote as much as a quart of milk each day for children. In 1921, the University of Wisconsin published Milk Drinks for Everyone, a circular with a two-fold premise: Milk is nutritious food that many children refuse to drink. It recommended milkshakes as they had been made for generations: cold milk, shaken or beaten with ice and flavored syrup. Cinnamon, nutmeg, or crushed macaroons strewn atop would further entice mistrustful children. As would crushed nuts. And cherry-topped whipped cream. Yet these were still just milk drinks.

The author, John L. Sammis, described something so close to a classic diner milkshake that modern readers can almost taste it. In flagrant disregard of bartenders’ established nomenclature, South Dakota State University proposed fanciful monikers for similar drinks that played off cow breed names, including the Guernsey Highball (a root beer syrup milkshake), the Guernsey Flip (milk fortified with lime-flavored Green River syrup), and the Holstein Julep of milk, cherry syrup, and an egg.

Nineteenth-century ice cream milkshakes were sporadic, fleeting treats, partly because mashing and shaking ice cream into cold milk by hand, especially for crowds, is physically taxing. Milkshakes thick and heavy with ice cream only achieved sustained popularity during Prohibition, thanks to the invention of Polish immigrant Stephen Poplawski and a Walgreens employee who understood the machine’s potential.

Soda fountain habitués of the era fawned over the toasty, praline flavor of malted milk, a combination of malted barley, wheat flour, and powdered milk. The hitch was that it tends to clump in cold, shaken milk. In 1922, Poplawski patented the first electric blender, essentially a mixing glass with rotating blades, to solve that problem. He called it the Beverage Mixer.

That same year at a Walgreens soda fountain in Chicago, Iver O. Coulson slipped two scoops of vanilla ice cream into a soda fountain standard of milk, chocolate syrup, and malted milk powder, then blended them in Poplawski’s invention. It was a sensation. Within a year, every Walgreens store in the country was selling Coulson’s “double rich chocolate malt.” Within 20 years, Walgreens owned a malted milk factory in Illinois to supply its stores.

In time, blenders became more powerful and efficient. Poplawski’s improvements on his own design led to a machine for home use later called the Osterizer. When inventor Frederick Osius brought his patented Miracle Mixer to radio personality Fred Waring, the bandleader bankrolled production and relentlessly promoted it, changing its name to the Waring Blendor. By 1954, he had sold over a million of the machines. Powerful blenders like Poplawski’s and Waring’s reshaped Gilded Age milkshakes from slightly thickened, cold milk drinks to nearly frozen ice cream drinks with just enough milk to make them pourable.

As an ice cream drink, the 20th-century milkshake’s only serious contenders have been its legions of imitators. United States federal code defines ice cream down to the amount of air it may contain, but is silent on milkshakes, leaving their parameters to states. For restaurants with regional or national reach, the simplest way to sidestep dozens of states’ conflicting milkshake definitions within their territories is not to sell milkshakes.

Many, instead, offer “shakes” or milkshake-adjacent frozen dessert drinks with branded names that suggest creamy coldness, but avoid the legal entanglements of calling them “milkshakes.” Some are in every way classic 20th-century milkshakes. Many, however, are simulacra. They look like milkshakes, and they pour like milkshakes, but achieve the effect with artificial sweeteners and flavorings, glycerin, oils, and other nondairy stabilizers and emulsifiers that make them smoother, less icy, and less costly to produce. A soft-serve machine outfitted with a spindle and flavor nozzle can churn out a new shake every fifteen seconds. When a flavored batch of soft-serve-based shakes is churned in a frozen drinks machine, drinks like frozen milk punch or frozen Irish coffee can be had in as little as four seconds. Even powerful modern blenders can’t beat that speed. (Read Milkshake Monday author Larry Canam’s tip for how to make a milkshake without a blender here.)

A good milkshake is rich in butterfat and heavy for its size, the way choice fruits and vegetables often are.

Because they can be dispensed quickly and cheaply, fast food shakes cost less than similarly sized milkshakes made with hard ice cream. Shakes made with light, airy soft serve also weigh less than those made with traditional ice cream. A good milkshake is rich in butterfat and heavy for its size, the way choice fruits and vegetables often are. It’s a hefty handful that makes you crave one more sucking, soulful slurp as you chase its disappearing tail with a fat straw into the corners of the cup or bottom of a glass.

Slurping a milkshake’s last moments is one of the few times Americans of any age are forgiven truly loud public consumption. A satisfaction takes hold, a fullness that makes you think, “Maybe I should have gotten the large.” A good “shake” can leave that impression as well. But too often the cheap ones taste of slightly cooked powdered milk, while the worst leave oily residues in their wake.

Milkshakes have long been arenas of experimentation and innovation. In the last decade, a particular style of playful social media bait known as freakshakes has made global inroads.

Festooned with inordinate amounts of garnish, freakshakes are spectacles of excess that can rival the size of a house cat.

In the past, particularly large American milkshakes were sometimes called “monster” shakes. The largest of them measured a quart or more. Festooned with inordinate amounts of garnish, freakshakes are spectacles of excess that can rival the size of a house cat. Frequently served in Mason jars, they are towering accretions of the types of snacks and sweets that some shops blend into milkshakes or their thicker cousins, concretes. A freakshake may be topped with cake, pie, doughnuts, cupcakes, brownies, or other baked goods. The exteriors are typically adorned with miniature pretzels, cookies, wafers, chocolate candies, rainbow sprinkles, or roasted nuts stuck into place with smears of marshmallow, ganache, peanut butter, salted caramel, or other sweet spackle. The whole thing may be garnished with whipped cream, cotton candy, and great ropes of sweet sauces. Through some oversight, it seems none so far has been garnished with a miniature milkshake.

Anna Petrid is widely credited with creating the genre, which she dubbed FreakShakes, in 2015 at Patissez Cafe in Canberra, Australia. Social media posts brought international attention. Within a year, similar milkshakes began appearing on menus the world over. In the United States, shops such as Nashville’s The Legendairy Milkshake Bar specialized in them. In 2017, Logan and Chelsea Green of Gulf Shores, Alabama, opened The Yard Milkshake Bar tethered to the concept of these over-the-top milkshakes. Today, The Yard has 29 locations from Florida to Washington state.

Aficionados understand that, regardless of any mix-ins, a milkshake is a drink. Though it is thick, a proper milkshake must be so fully and completely blended that it can pass through a straw. When possible, milkshake serving glasses should be kept in a freezer until the pour is ready for the trinity of ice cream, milk, and syrup. Retired TGI Friday’s bartender Jim Mancini describes the shape of the drink at the precise moment everything comes together in a blender: “It’s done when the top looks like a perfect baby’s butt.”

Juliet Pries, owner of The Ice Cream Bar and the closed The Castro Fountain ice cream parlors in San Francisco, describes her ideal milkshake. It starts with hand-scooped hard ice cream, “not soft serve. It should be cold and thick,” she says. “In the old days, you’d keep your milk in the coldest part of the cooler so it would be partially frozen.”

Staff will blend any of their ice cream flavors into shakes, but Pries recommends keeping it simple. “I don’t mind if customers want to mix flavors, but two or three is good. Beyond that, everything becomes muddled.” She adds that inclusions, such as chopped cookies or brownies, should be folded in at the end to maintain their size and shape. On top: real whipped cream and a single sour morello cherry in caramelized sauce. “And it’s got to have salt.” Pries feels so strongly about the benefits of salt that all of her ice creams include it.

Adam Ried concurs. Ried is an American cookbook author whose 2009 book, Thoroughly Modern Milkshakes, reveals a sophisticated understanding of taste combinations. “These days, it is standard operating procedure to salt many sweet dishes, so we’re used to it. Who doesn’t like salted caramel?” He calls for a pinch of salt to bring out or balance flavors in milkshakes, particularly those that already have a salty component such as peanut butter or thick-cut, butter-toasted oats, where salt reinforces those tastes. Salt likewise intensifies the flavor of fruit or fruit purées in milkshakes.

Ried also advises a surprise ingredient: sorbet. This sweet ice is typically flavored with fruit, and sometimes nuts, herbs, and spices. Through a certain lens, sorbet is little more than intensely flavored frozen syrup, with more concentrated flavors than those of commercial syrups typically found in modern ice cream parlors.

“One night I was eating a bowl of chocolate sorbet and thought, ‘Hmm, that could be good in a milkshake.’” He scooped some into a blender with coffee ice cream, blended both with milk, and was astonished by the intense chocolate flavor of his mocha shake. That led to further experimentation, a piece for his column in Boston Globe Magazine, and, eventually, his milkshake book that included several recipes that use sorbet to boost a shake’s flavor. Although he feels that the range of commercial sorbet flavors is not as extensive as it was in the early 2000s, adding the right sorbet to a milkshake can still be a pretty clutch move.

For garnish, traditionalists favor simple adornment: whipped cream and fruit preserves. They may also add roasted nuts, a cookie, or syrups drizzled over a drink or across the interior of the glass. Whether to raise a freak flag beyond that is entirely up to the drinker.