Which ingredient adds sweetness to a Lynchburg Lemonade cocktail?

The ingredient that adds sweetness to a Lynchburg Lemonade cocktail is Triple Sec. This is a type of orange-flavored liqueur that contains sugar, which provides the necessary sweetness to balance out the tartness of the lemon juice and the crispness of the soda water. In the context of a Lynchburg Lemonade, Triple Sec not only contributes sweetness but also enhances the overall flavor profile with its citrus notes, making it a key component of this refreshing drink.

In comparison, soda water is primarily used for dilution and does not contribute sweetness. Lemon juice, while essential for the cocktail's tart flavor, does not add any sweetness but rather a sharp, acidic note. Grenadine, known for providing sweetness and a vibrant red color, is not typically used in a traditional Lynchburg Lemonade recipe, which focuses on the combination of whiskey, lemon juice, and Triple Sec.