Acidity is the difference between a cocktail that tastes crisp and “finished” and one that feels flat, heavy, or overly sweet. It is also one of the fastest ways to improve consistency: citrus changes from day to day, while a measured approach to acidity can keep a drink tasting the way it was designed.

Shrub is a sweet and tart syrup made with fruit, sugar, and vinegar. It is used like a flavor concentrate. Add a small amount to soda for an instant non-alcoholic drink, or use it in cocktails as a fast way to build fruit, acidity, and aroma in one ingredient.