IT WOULD be lovely to have access to chromatography," Spike Marchant tells me wistfully. As a science journalist, it's the kind of remark I expect to hear from the people I interview. But Marchant isn't a scientist, he's a bartender.
A very special breed of bartender, mind you. What Heston Blumenthal, Ferran Adrià and others have done for food, Marchant and his colleagues are aiming to do for booze. "We're not scientists but we use the ideas of scientists," says Tony Conigliaro, the creative force behind 69 Colebrook Row, a cosy cocktail bar in north London where I have come to learn about, and taste, the future of cocktails.
Their quest is a logical extension of the molecular gastronomy movement. Over the past couple of decades, leading chefs and pioneering scientists such as Hervé This have been thinking differently about food and cooking. Just because certain dishes have always been made in a certain way, does that make it the right way? Can science explain, or even improve on, culinary tradition? Thus was born a revolution of mouth-watering tastes and techniques.
That way of thinking is now being applied to mixology, the art of making cocktails. "People are thinking about cocktails in a more experimental and exploratory way," says food and science writer Harold McGee. "It's about tools and ingredients that have not been used in cocktail-making before." Not surprisingly, the term "molecular mixology" is bandied about, though mixologists themselves don't seem to like it.
I am led upstairs to Conigliaro's laboratory - a cramped, low-ceilinged cross between a kitchen and a chemistry lab, stuffed with shiny bits of kit. The first thing he shows me is a temperature-controlled water bath. It would not look out of place on a lab bench, but is actually a piece of kitchen equipment designed for a technique called sous-vide (French for "under vacuum"). In sous-vide cooking, food is sealed in a vacuum bag and gently cooked for hours or even days at low temperatures, typically 70 °C or less. Chefs say it preserves the delicate flavour molecules that are lost at higher temperatures or through typical extended cooking.
Conigliaro uses his to make rhubarb-infused gin. "I discovered that if you cook the fruit in alcohol under vacuum at precisely 52 °C, you get a cleaner, brighter, more accurate flavour," he says. "It's also much better than marination. If you just dunk the rhubarb in, the fruit falls apart." Conigliaro has used this technique to infuse clean flavours into all kinds of spirits - raspberries into tequila, rose petals into vodka, blackcurrants into gin.
As I'm quickly discovering, molecular mixologists are obsessed with flavour. "Cocktails are simpler than food; they're essentially all flavour," says McGee. That explains the heavy use of another of molecular gastronomy's magic ingredients: food-grade essences.
These super-concentrated extracts can be used in minute quantities to add unexpected flavours to drinks. Conigliaro tells me that he is experimenting with the champagne cocktail (usually made by pouring bubbly over a sugar cube soaked in bitters) by ditching the bitters and pipetting a few microlitres of an essence onto the cube instead. The aroma is delivered straight to your taste buds inside the bubbles.
Food-grade essences can add very strange flavours indeed. Conigliaro pulls a small brown glass bottle from the shelf and opens it for me, releasing a beautiful, intense smell of leather. He uses this, along with essence of tobacco, in a version of the Old Fashioned (sugar cube, bitters, bourbon, splash of soda water, orange slice, lemon twist, two maraschino cherries). The idea is to create the aura of a gentlemen's club.
Among the techniques at Conigliaro's disposal, vacuums loom large. He tells me about one of his latest creations, the Somerset sour (apple brandy, lemon juice, sugar, egg white, cider), inspired by the smells of early autumn. The cocktail includes a little treat: a miniature bobbing apple, made by melon-balling a particularly crisp variety, the pink lady. Conigliaro gives me one to eat; it is crunchy and intensely appley but also tastes of something that I can't put my finger on. "It's hay," he finally tells me.
Mixologists are full of surprises. My drink includes a miniature bobbing apple that tastes of hay
The apple balls have been infused with essence of freshly mown hay using a technique called reverse vacuuming. Conigliaro shows me how it's done. First he puts apple balls and a few drops of the essence into a vacuum chamber and gradually withdraws the air. This sucks the juice out of the apple to mingle with the essence. Then he releases the vacuum, forcing the hay-flavoured apple juice back in. The technique is invaluable for adding unexpected flavours. "We've made pineapples taste of ginger, apples taste of pineapple, cherries taste of orange," says Marchant.
