One of the more neglected liquid flavors is vinegar, most people think of it and their mouth puckers up. But while white wine vinegar is quite tart, it also brings out the sweetness in its surrounding flavors, which makes it a very interesting replacement for citrus in cocktails. It just so happens that people figured this out quite some time ago, making a concoction called the Shrub in American Colonial times. It was an excellent way to preserve fruit for long time without refrigeration and it turned out that the mixture of vinegar, fruit and sugar tasted incredible.

Eric Felten’s incredible book “How’s Your Drink?” covers a lot of the background on the drink and has the recipe for both the shrub syrup and the rum shrub cocktail:

Directions
Bring water to a boil and stir in sugar. Reduce the heat and add the raspberries stirring for 10 minutes. Add Vinegar and bring to a boil for 2 minutes. Let cool and strain into a bottle, and keep refrigerated.

Directions
Shake the rum and shrub over ice and strain into an ice filled glass. Add ginger ale and lightly stir to mix.