Ice does three primary functions in every cocktail. First, it lowers the temperature of the drink. Secondly, it adds water to the drink. Third, it adds texture to the drink.
Let’s first focus on the cooling of the drink aspect:
As a drink gets colder, our ability to experience different tastes change. For example, we would need to add some more sugar to taste sweetness. We would need to add more bitters, to taste bitters. We also dull our sense of tasting alcohol, which helps lower quality spirits become more palatable. Moreover, there’s a cooling sensation that occurs as well while drinking a cold drink. It feels refreshing.
Secondly, water affects flavor:
People typically have trouble differentiating flavor in water. But in cocktails the addition of water becomes apparent. When there’s too much, a cocktail will become diluted and taste weak. When there’s too little water, the cocktail will taste strong and it’ll be difficult for many to discern the flavor profiles over the alcoholic burning sensation that occurs.
The addition of water also has a slight flavor and gives cocktails a sort of regional difference that is slightly noticeable! For example, a New York City made Old Fashioned, will taste completely different than the same exact drink being made in Berlin, Germany with the only difference being the water used! Every municipal has different chemical additions they add to water during the water treatment process, and while most treated water is almost completely distilled, there are still some trace minerals that are added like: Fluoride, Magnesium, Sodium, Calcium, and many other minerals.
Many water bottles, specifically higher end waters, will actually list the PH and other minerals so you can try making ice with them and seeing how it compares!
For texture, there are thousands of different sized ice cubes. The usage of crushed ice makes it so that a 16 oz hurricane glass, could be filled with as little as 3 oz of mixture. Traditionally, bars preferred to use “nugget ice” or “crescent ice” (both pictured below), to impress guests by making them perceive there is more volume in there drinks, while it's all just cheap water!
Recently, consumers have gotten smarter, and larger blocks of ice have been used in higher end bars. This is preferred because top bartenders have noticed that there is a sweet spot in flavor after a certain amount of dilution. In order to keep it at that constant, peak, flavor, they will also prefer to use ice that is large that it barely fits in a glass, but also shaped in a sphere as it exposes the least amount of surface area, and thus melts slower than another shape of ice.
Finally, there are other ways ice affect tastes, for example, it does also change the PH level of the cocktail!
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