A splash of water in a whiskey can enhance its aroma and taste, but a study led by Washington State University has shown adding too much can ruin your experience.

The senior author, WSU assistant professor Tom Collins, said, “If you want to enjoy a specific whiskey, this suggests that you don’t want to dilute it by more than about 20%.”

As whiskey is made of ethanol — alcohol — and water molecules, adding more water to the mixture alters the entire makeup of the combination.

Calum Fraser of Bowmore shared, “Due to molecule-by-molecule variation in solubility in water, this can cause certain flavors to be more ‘visible’ to the nose.”

However, adding more than 20% water can make most whiskeys taste the same, making your high-end whiskey have a flavor no different than bottom-shelf whiskey.

While some argue whether whiskey needs water at all — and that adding water dismantles the flavors of the barrel — experts say that it depends on its age.

It’s unlikely older whiskeys will need it, but Fraser revealed that adding water to younger whiskeys “reduces the intensity of the alcohol, unmasking all the flavors.”

While it comes down to personal preference, sticking to the 20% rule will provide enough water to remove the burn of the alcohol to help release the aromatic compounds.