The whisky sour explained
The whisky sour is the cocktail most people meet first. It is also the one that most clearly shows whether a bartender can balance sour against sweet. Here is how to make it properly at home.
A sour is spirit, citrus and sugar in balance
A classic spec is 60 ml of whisky, 30 ml of fresh lemon juice and 20 ml of simple syrup (equal parts sugar and water). Many bartenders add one egg white, roughly 30 ml, for texture. Shake hard with ice and strain into a chilled glass, with or without fresh ice. A few drops of Angostura on the foam make it look and smell finished.
The ratio is a starting point. Citrus varies from fruit to fruit, so the syrup is the dial you turn. Move it 5 ml at a time until the drink tastes neither sharp nor sweet.
Fresh juice is not optional
Bottled lemon juice tastes flat and slightly cooked. Squeeze your citrus on the day, ideally within a few hours of using it. A hand press is cheap and faster than it looks.
In India you will often be using nimbu, the small kagzi lime, rather than a large lemon. It is sharper and more aromatic. That is fine. Start with 25 ml instead of 30, taste and adjust. Strain out the seeds and pulp so they do not end up in the glass.
Shaking does three jobs
A hard shake of 10 to 15 seconds with plenty of ice chills the drink, dilutes it and whips in air. The air matters more here than in stirred drinks. It gives a sour its lively, slightly frothy texture even without egg.
Use large, solid ice cubes. Small or wet ice melts too quickly and leaves a thin drink. When the outside of the shaker frosts over, you are done.
Egg white is for texture and needs care
Egg white turns a sour silky with a thick white cap. To get the foam, shake everything without ice first for about ten seconds (a dry shake), then add ice and shake again. Some bartenders reverse the order. Both work.
Raw egg carries a small food safety risk. Use very fresh eggs from a source you trust, or pasteurised egg white from a carton. For vegetarian or vegan guests, aquafaba, the liquid from a tin of chickpeas, foams in much the same way. About 20 ml does the job. The drink is just as good without any foam at all.
Simple syrup that keeps
Simple syrup is equal weights of sugar and water. Warm the water, stir in the sugar until it dissolves and let it cool. Bottle it clean and keep it in the fridge, where it lasts a couple of weeks. A rich syrup at two parts sugar to one of water keeps longer, though you need less of it, about 15 ml in place of 20.
Swaps are easy. Honey thinned with an equal amount of warm water gives a softer, floral sour. Jaggery syrup gives a darker, toffee-like one that suits bourbon. Whatever you use, measure it with a jigger. Free pouring is where most sours lose their balance.
Glass, ice and garnish
A sour served over fresh ice in a rocks glass stays cold longer and suits Indian evenings. Served up in a chilled coupe without ice, it shows off the foam but warms quickly. Both are correct.
The traditional garnish is a slice of orange and a cherry. With egg white, a few drops of bitters on the foam do the job instead and add aroma to every sip.
Pick the whisky for the job
Bourbon is the classic choice. Its vanilla and caramel, which come largely from new charred oak casks, sit well against citrus. A smooth blended Scotch makes a lighter sour. A peated malt makes a smoky one, which is also the idea behind the Penicillin. Indian blends work well too and are a sensible choice for a cocktail.
What does not work is a rare old malt. Citrus and sugar flatten the subtle notes you paid for. A New York sour floats a little red wine on top, which is worth trying once you have the basic drink right.
Make two and compare
Pick one whisky and make two sours side by side, one with egg white and one without. Taste each and note the difference in texture, aroma and how sharp the citrus seems. Most people find the egg white version tastes less sour even with the same ratio.
Then keep the one you prefer as your house spec and write it down. Change one thing at a time from there. A sour has 60 ml of whisky in it, so make the comparison a shared tasting rather than two drinks for one person.
Common questions
Do you need egg white in a whisky sour?
No. Egg white adds a silky texture and foam, but the drink is complete without it. Aquafaba is a vegetarian alternative.
Can I use lime instead of lemon?
Yes. Indian limes are sharper, so start with slightly less juice and adjust the syrup to taste.
What is the best whisky for a whisky sour?
Bourbon is the classic. Blended Scotch and Indian blends work well. Save rare malts for drinking neat.
