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Meet the Flower That Naturally Colors Drinks Blue

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Butterfly pea flower will give you the blues.

"Suppose I were to begin by saying that I had fallen in love with a color," author Maggie Nelson writes at the beginning of Bluets, a book that bobs and weaves its way through the landscape of human emotion using the cool depths of the color blue as both a winding wheel and touchstone.

The lyrical collection of essays calls us to see blue (periwinkle, sky blue, robin’s egg blue) as a color uniquely able to conjure up emotion. "And so I fell in love with a color—in this case, blue—as if falling under a spell," Nelson confesses. "A spell I fought to stay under and get out from under in turns."

Lusting after the blue(s), after all, is only human.

Blue is a color that both fascinates and eludes us in the natural world, and its appearance is often cause for celebration or—at the very least—immense curiosity. "There is so little blue food in nature … culinary advisers generally recommend against blue light, blue paint, and blue plates when serving food," Nelson notes. The scarcity of such a critical hue on our plates and in our drinks has long simply been accepted with a shrug or a grasping-at-straws scientific explanation.

Sure, there are blueberries (that, let’s not kid ourselves, aren’t really that blue) and the rare, bright azure fruits of Australia’s blue quandong tree, but they’re the exception to the rule—so rare that we have to be prepped for the shock of their colorful arrival by sticking "blue" in their name.

Butterfly pea powder—used to dye drink and food shades of blue for centuries—is an exception that comes with no warning label.

Butterfly pea powder is derived from the butterfly pea plant, a vining flower that has crept along trellises and up the sides of buildings across Thailand and Burma for centuries. The plant’s petals are a pulsing indigo, and have the appearance of a flared, soft tongue, ready to lap up the morning dew. More accurately, the flower is shaped almost identically to a woman’s clitoris. The similarity is so uncanny that the plant’s official scientific name is Clitoria ternatea: literally "clit tea." The flowers bloom both voraciously and fleetingly—particularly during monsoon season—blossoming around sunrise at 6 a.m. and lasting only 24 hours before withering.

Butterfly pea plants have long been used to create a natural dye for edible dishes across Southeast Asia, including the popular Malay gluttonous rice dish kuih ketan, which causes cream-colored sticky rice to turn a shade of blue that rivals the peacock’s satiny sapphire body. A style of steamed dumplings shaped like (you guessed it) flowers— chor maung—derive their periwinkle hue from butterfly pea buds and have been lauded in the pages of Thai literature for centuries.

In both cases, the flowers are simply steeped (or mixed with the food itself) until the desired pigment is reached, taking an act as painstakingly simple as boiling water and turning it into a veritable visual feast. Alternately, the flowers are made into a powder instead of a concentrate, then sprinkled into dishes.

... butterfly pea ... allows bartenders to craft drinks with a cool-hued, sunset-style color spectrum without relying on the artificial tricks of the trade from the 1970s ...

Butterfly pea buds themselves have a subdued flavor similar to a slightly more herbal black tea, but the plant primarily functions as a natural dye that’s subtle in flavor but bold in visual pop. The flowers are most famously used to make a traditional Thai welcome tea known as dok anchan, which hotels there frequently serve to travelers upon their arrival.

Both hot and cold versions of dok anchan are widely offered, prepared in an almost identical fashion. Butterfly pea pods (about 10 per glass) are soaked until their color begins to bleed out, then the drink is consumed either piping hot or on ice with a dollop of treacly honey and a wheel of lemon or lime on the side. The burst of citrus causes the drink to have a punchy aftertaste, but it also serves a more arresting purpose—making the drink change colors.

Butterfly pea tea has an incredibly sensitive pH balance, meaning even the slightest shift in acidity can turn a beverage from deep blue, to a vibrant plum, to a fizzy magenta. The drink becomes a sippable chameleon: The more acid that comes in contact with the tea, the lighter in color it becomes. From pH 8 to pH 4, the tea is a regal shade of blue. It quickly shifts into deep purple terrain at pH 3, and finally bursts into carnation pink territory at pH 2.

And after centuries of use in Southeast Asia for health purposes like strengthening hair follicles and helping fight depression, butterfly pea tea and its concentrate have suddenly found themselves thrust into an unusual limelight. With the recent rise in boozy blue beverages, butterfly pea concentrate is quickly becoming a darling of the cocktail world. The tincture allows bartenders to craft drinks with a cool-hued, sunset-style color spectrum without relying on the artificial tricks of the trade from the 1970s "blue drinks" period.

Check out Charleston restaurant 492's color-changing Disco Sour.

Of course Blue Curaçao comes to mind, and it's no secret that the liqueur's brilliant azure hue is anything but natural. A synthetic E133 "Brilliant Blue" dye is mixed in post-production as a means of shading the liqueur the desired oceanic color.

Butterfly pea syrups, powders, and concentrates are shoving the theatrical colors of blue drinks back into the limelight.

In addition to the strange mental disconnect that occurs when comparing its syrupy sweet orange flavor with its unexpectedly blue color, Curaçao has been much maligned for being so unabashedly synthetic, relegating blue drinks to the history books of the cocktail’s dark age for far too long. When Don Draper orders a "Blue Hawaii" (vodka, Curaçao and rum) in season six of Mad Men, it’s hard not to wince when the treacly drink as it hits his (admittedly, still desirable) lips.

In a world much more concerned with both authenticity and health (Curaçao’s dye has also been linked to allergic reaction among asthma sufferers) than the freewheeling 1970s, it’s not surprising that bartenders have gleefully latched onto a way to color their indigo drinks without influencing flavor. Butterfly pea syrups, powders, and concentrates are shoving the theatrical colors of blue drinks back into the limelight.

The flower has finally made its way into rocks glasses primarily by way of the first-ever commercially produced concentrate from the Wild Hibiscus Flower Company, b’lure. Packaged in a dropper bottle, b’lure is essentially a butterfly pea simple syrup that enables drinks to appear just a little more oceanic with a few drops of the liquid rationed out like dashes of bitters.

Bartenders have readily taken to the enchanting tincture, creating over-the-top psychedelic foams, ice cubes, and jelly layers that make sipping a drink more akin to a (quasi-healthy) acid trip.

In Las Vegas, the bar program at the Bellagio’s Lago uses the elixir to triple up on the floral note within its namesake cocktail, combining vodka, vermouth, orange blossom syrup, and butterfly pea extract with a seasonal flower ice sphere. At restaurant 492 in Charleston, the performance art stylings of the the Disco Sour cocktail is upped by plunking blue-tinged ice cubes into the glass, giving off the appearance of pulsing dance floor lights as they melt into pink.

While butterfly pea is still flying somewhat under-the-radar, it’s heartening to finally see a color that’s so long captivated imbibers finally finding its way among the coral-colored Palomas and juicy, ruby-hued Bloody Marys.

Through butterfly pea flower, we’re finally managing to plug the missing link into the cocktail color rainbow.

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