Why is distillation needed to make strong alcoholic drinks?

Distillation is needed to make strong alcoholic drinks because it allows for the concentration of alcohol in a fermented beverage. During fermentation, yeast converts sugars from grains, fruits, or other sources into alcohol. However, the alcohol content of fermented beverages is limited to around 15% ABV (alcohol by volume) due to the yeast's own intolerance to alcohol.

Distillation involves heating the fermented beverage to a temperature where the alcohol vaporizes, and then condensing and collecting the vapor back into liquid form. By selectively evaporating and condensing the alcohol, it is possible to increase the alcohol content of the resulting distillate well beyond the limits of fermentation. This higher concentration of alcohol is what characterizes strong alcoholic drinks.

For example, whiskey, vodka, rum, and gin are all produced through distillation, with alcohol contents ranging from around 40% ABV to over 50% ABV. Distillation also allows for the separation and concentration of specific flavor compounds and aromas, influencing the taste and quality of the final product.