Why the Ratio Works
Cocktail making is all about balancing the flavors in an alcoholic beverage.
Alcohol takes up half of the entire cocktail because it’s the main ingredient we intend to consume. The sweet and sour ingredients complement and enhance the alcohol instead of hiding its taste.
Sweet and sour flavors normally complement and balance each other out. In cooking, for instance, sweet and sour combined are perfect with pork. Likewise, sour cocktail ingredients serve to put some zing, while sweet ingredients temper the alcohol’s bitter flavor.
Using Other Forumulas
Take note that the golden ratio isn’t the only formula used in cocktail making. It merely serves as a starting point, because you can use other ratios as well.
There’s the noteworthy 1948 book ‘The Fine Art of Mixing Drinks’ by David A. Embury which recommends an 8:2:1 (alcohol-sour-sweet) ratio for various cocktails like Jack Rose and Daiquiris. Some prefer a 2:3/4:3/4 ratio.
Now that you know the basic golden ratio, you can customize your own formula to suit your own tastes. This would likely depend on how strong you want the alcohol to taste.
Just bear in mind that while cocktail making has its own quantifiable science, it’s an art form as well. The art is in knowing the tastes you’re combining, then layering them to achieve certain flavors of varying intensity.