I had never heard of shrub until my friend Patsy brought me a bottle of raspberry shrub she’d made from an old family recipe. It seems to be a New England thing, dating from colonial times, made from an extravagant amount of raspberries cooked with sugar and when cool, dosed with vinegar. A gorgeous raspberry red, it made a wonderful drink with a little gin and sparkling water. I even poured a little of the vinegary sweet-tart syrup over ice cream. Patsy tells me she likes it on blintzes and in her yogurt.
I just came across the sweetened vinegar-based drink again -- at Bäco Mercat -- where chef/owner Josef Centeno makes his own shrubs aka "drinking vinegars." They’re used for his alternative to Coca-Cola, namely “sweet and sour soda.” And also cocktails made with a variety of spirits. Centeno creates his shrubs with whatever’s in season — Meyer lemon, red grape, black mint, etc. He’s even made a chile-lime vinegar for their version of the margarita.
As customers get into the idea of drinking vinegar, he’ll sometimes give them a small bottle of, say, tangerine drinking vinegar, enough to make two sodas. Those sweet little bottles are not for sale yet, but maybe soon.