Vinegar: bringer of health, enhancer of flavour – and your new favourite cocktail ingredient.

Although vinegar has been widely used across cocktail history, it is the modern-day penchant for building libations based on shrubs (a tangy alloy of juicy, sweetened fruit and tart vinegar) that has seen this sorcerous ingredient once again rise to prominence.

“Vinegar is great in cocktails,” agrees Iain Griffiths, renowned White Lyan and Dandelyan bartender, and finalist of the Bacardi Legacy 2016 ‘Three Most Promising’ competition. So ardent is his admiration for the tonic that he developed the Carta Switchel, a boozy homage to history, heritage and the mighty v-word.

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Based on a 17th-century recipe, the Switchel is a distant cousin of the shrub, its fusion of fruit and vinegar laying the groundwork for a long, cool, health-giving (maybe) drink.

Thought to have originated in America, it is said to have been invented by sugarcane plantation and hayfield workers, who ached for a long and frosty refresher during the arduous summer months – although, the classic Switchel was actually a non-alcoholic draft, and was widely considered a Puritanical substitute to heavy spirits. It called for equal parts molasses, ginger, vinegar and water, which, Griffiths assures us, “tastes ghastly”.

“I sub the molasses for a good few slugs of Bacardi, and use the bittersweet flavour of grapefruit to give the drink some spice and much needed pop,” he says. “The vinegar brings a citrusy pucker to the drink, lifts the aroma and adds depth to the rum.”

The addition of Fernet Branca is another of Griffith’s innovations. An Italian bitter, he uses it sparingly here, a few quick dashes adding folksy spice notes, herbal richness and an extra sling of fermented vim. “It’s like Jägermeister on steroids,” he says.