What is a common ingredient in many cocktails that provides sweetness?

A common ingredient that provides sweetness in many cocktails is sugar syrup. Sugar syrup, often made by dissolving sugar in water, is frequently used to balance the flavors in cocktails. Its sweetness can enhance the overall taste profile of drinks, making them more palatable and enjoyable. This ingredient is versatile and can be adjusted to meet the desired level of sweetness in various recipes, contributing to the balance between sweet, sour, and bitter components.

In contrast, salt is typically used in very small amounts to enhance flavors rather than provide sweetness. Cinnamon is a spice that adds warmth and complexity but does not impart sweetness in the same way sugar syrup does. Olive brine, often used in specific cocktails, contributes a savory and briny flavor rather than sweetness. Thus, sugar syrup is the key ingredient recognized for adding that essential sweetness in cocktail mixology.