Several years ago, I was enjoying a drink (at a now-shuttered restaurant) so much that I complimented the bartender on my cocktail. He nodded in agreement and replied, “Shrubs are cool.” I am ashamed to admit I had no idea what he was talking about. (That’s not entirely true. There was muddled thyme in my cocktail, so I assumed he was referring to that.) Only very recently did I connect that statement with the Martha Washington Raspberry Shrub served at City Tavern, even though I have walked by the sign advertising said shrub at least a thousand times.
Needless to say, I am an extremely late-comer to the possibilities of fruit shrubs. (For those readers who truly are the last people on Earth to learn of them, shrubs are fruit-based syrups mixed with vinegar.) One day several weeks ago, I decided to experiment with some underripe strawberries, using this recipe. After a little more research, I came about this from Michael Dietsch. Taking Dietsch at his word, I used the cold method for my next shrub. However, I wasn’t using strawberries this time; I was using rhubarb recently picked from our garden.
The result was definitely more flavorful, and Dietsch is absolutely correct that the acid mellows in time, but this shrub did not have the viscosity of the cooked one. I am confident enough in the cold method to use it for any other fruit, but given the texture of rhubarb, I think I would use the “hot” method in the hopes it might further break down and exude its juices. Nonetheless, Dietsch’s cocktail recipe was much better than the previous, and it made a delicious cocktail with club soda and Bluecoat Gin.