Quick answer
An arrack sour is made with 60 ml of coconut arrack, 25 ml of fresh lime juice and 15 to 20 ml of sugar syrup, shaken hard with ice and strained into a chilled glass. Adding 15 ml of egg white before shaking gives a silky foam, and two dashes of aromatic bitters on top finish it. Use a pure coconut arrack at around 40 per cent so the spirit stands up to the citrus. In Sri Lanka, bartenders often replace the sugar syrup with kithul treacle.
Key takeaways
- The basic arrack sour ratio is roughly four parts arrack, two parts lime juice and one part sugar syrup.
- A pure coconut arrack at around 40 per cent ABV gives a better sour than a light blended arrack.
- Egg white is optional in an arrack sour and adds texture and foam, not flavour.
- Kithul treacle, the syrup of the fishtail palm, is a popular Sri Lankan substitute for sugar syrup in a sour.
- Freshly squeezed lime juice is essential; bottled juice makes a flat, harsh drink.
What an arrack sour is
An arrack sour is a member of the sour family of cocktails: spirit, citrus and sweetener, shaken and served short. It is built exactly like a whiskey sour or a daiquiri, with coconut arrack as the base.
An arrack sour suits the spirit particularly well. Lime sharpens arrack's floral notes and sugar rounds its dry finish, so the cocktail tastes of arrack more clearly than a long drink with ginger beer or cola does.
Arrack sour ingredients
Arrack sour ingredients are few, so each needs to be good. Measures below make one drink.
- →60 ml pure coconut arrack, ideally around 40 per cent.
- →25 ml freshly squeezed lime juice, about one large or two small limes.
- →15 to 20 ml sugar syrup, made with equal parts sugar and water.
- →15 ml egg white, optional.
- →Two dashes of aromatic bitters, optional.
- →Ice, and a slice of lime to garnish.
How to make an arrack sour
Making an arrack sour takes about two minutes. A shaker is ideal, though a lidded jar does the job in a villa kitchen.
- →Chill a short glass or coupe with ice and water.
- →Add arrack, lime juice, syrup and egg white, if using, to the shaker.
- →If using egg white, shake hard without ice for ten seconds to build foam.
- →Add ice and shake hard for another ten to fifteen seconds.
- →Empty the glass, strain the drink in and dot the bitters on top.
Sri Lankan twists on the arrack sour
Sri Lankan twists on the arrack sour draw on the island's own sweeteners and spices. Most swap or add a single ingredient.
- →Kithul sour: replace sugar syrup with 15 ml of kithul treacle for a smoky caramel note.
- →Ginger sour: muddle two slices of fresh ginger in the shaker first.
- →Cinnamon sour: use a syrup infused with Ceylon cinnamon.
- →Passion fruit sour: add the pulp of half a passion fruit and reduce the lime slightly.
- →Tea sour: add 20 ml of strong, cold Ceylon black tea.
Choosing the arrack for a sour
Choosing the arrack for a sour makes more difference than any technique. Lime and sugar are strong flavours, and a thin spirit vanishes behind them.
Pure coconut arrack at 38 to 40 per cent is the best base. A double distilled arrack is a good second choice. Extra special arrack makes a weak, sweet sour, and a 15-year-old arrack is wasted in the shaker.
Where to drink an arrack sour in Sri Lanka
An arrack sour is on the list at most cocktail bars and good hotel bars in Colombo and Galle Fort, and at many beach hotels along the south coast. Quality varies with the freshness of the lime and the care of the bartender.
Lankan Stays & Trails can recommend bars on your route that build their lists around arrack, and can arrange a short cocktail session at a hotel where you make the sour yourself.
Frequently asked questions
What is in an arrack sour?
An arrack sour contains coconut arrack, fresh lime juice and sugar syrup, shaken with ice. Egg white is often added for a silky foam, and a couple of dashes of aromatic bitters are placed on top. In Sri Lanka, kithul treacle frequently replaces the sugar syrup.
Do you need egg white in an arrack sour?
No. Egg white adds a smooth texture and a foam cap but no flavour, and the drink is perfectly good without it. Use about 15 ml of fresh egg white, or the liquid from tinned chickpeas as a vegan alternative.
Which arrack is best for an arrack sour?
A pure coconut arrack at around 40 per cent alcohol is best, because it has the flavour and strength to balance lime and sugar. Double distilled arrack also works well. Avoid the lightest blended arracks, which make a thin drink.
Can I use lemon instead of lime in an arrack sour?
Yes, though lime is traditional and suits arrack better. Lemon gives a softer, rounder sour. If you use lemon, reduce the sugar syrup slightly, since lemon juice is less sharp than the small limes used in Sri Lanka.
What is kithul treacle?
Kithul treacle is a dark syrup made by boiling down the sap of the kithul, or fishtail, palm, tapped in Sri Lanka's wet-zone hills. It tastes of caramel and smoke, is traditionally poured over buffalo curd, and makes an excellent cocktail sweetener.
Is an arrack sour strong?
An arrack sour made with 60 ml of 40 per cent arrack contains about 24 ml of pure alcohol, roughly the same as a large glass of wine. It is served short and goes down easily, so it is stronger than it tastes.