Egg White in a Whiskey Sour: Why, How Much, Safety & Substitutes

Egg white is the most argued-over half-ounce in the Whiskey Sour. Leave it out and you have the drink Jerry Thomas printed in 1887 and the one the IBA still lists with egg white marked optional. Put it in and you have what PUNCH calls its preferred version and what Difford's files under its own name, the Boston Sour: the same whiskey, lemon and sugar under a dense white foam that softens the acid and changes the texture of every sip.

This guide covers what the egg white is doing, how much to use, the dry shake that makes it work, the raw-egg safety question and the pasteurized and egg-free ways around it. The full egg-white build is on the Boston Sour page; the shaking mechanics in detail are in how to shake a Whiskey Sour.

The Short Version

• Optional, not required. The IBA lists it as optional; Jerry Thomas's 1887 recipe has none. With it, the drink is commonly called a Boston Sour.
• ½ oz per drink — roughly one small egg's white. PUNCH, Difford's and Jeffrey Morgenthaler agree.
• Shake it twice. A dry shake (no ice) builds the foam, then a shake with ice chills it. The reverse order gives a firmer head.
• Use pasteurized egg white. That is the FDA's guidance for raw-egg recipes and Difford's standing spec.
• Egg-free: 1 oz aquafaba, three dashes of Fee Foam, or simply leave it out.

What Egg White Does

Shaken hard, egg white turns into a fine, stable foam that sits on top of the drink and coats the mouth. It adds no sweetness and almost no flavor; what it changes is texture. The acid reads softer, the drink feels fuller, and the foam carries whatever you dash onto it — the Boston Sour keeps the same sweet-sour balance, with a silky, meringue-like foam and softer acidity.

Bartenders split on whether that is an improvement. On PUNCH's 2017 judging panel, judge Fu called egg white "a good way to experience that texture and foam and mouthfeel that sours call for." Co-judge Willey preferred the drink without it, while conceding that egg white gives "a visual snap" and is "really showy." A no-egg sour is sharper and more direct; an egg-white sour is rounder and more polished.

The practice is old. Robert Vermeire wrote in 1922 that "a few drops of white of egg improves all Sours," and the Oxford Companion dates egg white in the Whisky Sour from the 1920s.

Egg White or Not: Where the Sources Land

If you want the name to match the drink: a Whiskey Sour with egg white is a Boston Sour in Difford's and PUNCH's usage. Nobody has documented why; etymologist Barry Popik's entry on the name has no dated first citation.

How Much Egg White

Half an ounce. PUNCH specifies "½ ounce or 1 small egg white," Difford's uses ½ fl oz in its Whiskey Sour, Boston Sour and Rattlesnake, and Morgenthaler's Amaretto Sour uses ½ oz lightly beaten. The IBA's "few drops" gives a thin lace rather than a head; it is the minimum, not the target. Measure it into the jigger rather than guessing from the shell — more than ½ oz makes the drink taste diluted and the foam taste of egg.

The Dry Shake, and the Reverse Dry Shake

Ice breaks foam down, so the foam has to be built either before the ice goes in or after it comes out. Those are the two methods.

Dry shake: shake everything without ice first — Julie Reiner's rule of thumb on PUNCH is about ten shakes, roughly ten seconds — then add ice and shake again, then strain. Reiner tried the reverse method and went back to this one because it gave her smaller bubbles and better mouthfeel.

Reverse dry shake: shake with ice first, strain the drink back into the tin, discard the ice, shake again without it, and pour. Difford's uses this order for its Whiskey Sour, Boston Sour, New York Sour and Rattlesnake. In a Tales of the Cocktail test on a Ramos, the reverse order produced "the firmest, most meringue-like foam." The trade-offs: larger bubbles (Reiner) and a foam that settles faster (Ray Keane), and Tristan Stephenson's warning that over-shaking without ice gives an absurdly foamy drink.

There are dissenters: Rob Krueger argues proper ice and a proper shake make dry-shaking unnecessary; Steve Schneider shakes egg drinks with a single 2×2-inch cube; Morgenthaler froths the egg white with an immersion blender before shaking with ice. Step-by-step timing for all of this is in how to shake a Whiskey Sour.

Raw Egg: What the FDA Says

A Whiskey Sour is not cooked, so the egg white in it is raw. The FDA's position is plain: "Fresh eggs, even those with clean, uncracked shells, may contain bacteria called Salmonella." The groups it names as higher-risk are children, older adults, pregnant women and people with weakened immune systems. For recipes that use raw eggs, the FDA advises shell eggs that have been "treated to destroy Salmonella" — that is, pasteurized — or pasteurized egg products.

That is why Difford's writes "egg white (pasteurised)" into every egg spec it publishes, and why a carton of pasteurized egg whites belongs in the bar fridge; they foam the same way. If you are serving anyone in the higher-risk groups, the egg-free options below make a convincing foam.

Substitutes

One of nine entries in PUNCH's 2024 contest used aquafaba, and the judges noted that bitters on top help mask off aromas from egg white and aquafaba alike.

Up or On the Rocks With Egg White

PUNCH's 2017 judges preferred it up in a coupe, especially with egg: "I think egg whites on the rocks are gross… They break down quickly." Yet the 2017 winner is served on the rocks in PUNCH's 2024 write-up, and in 2024 "nobody was mad at the drink arriving on ice." Over ice, fine strain so no shards collapse the head. The glass choice is in best Whiskey Sour glass.

Finishing the Foam

Nearly every entry in PUNCH's 2024 contest dashed Angostura on the foam (one used Peychaud's); the judges said it masks egg aromas. Perry added an expressed lemon twist; Difford's Rattlesnake drags the dashes through the foam into a pattern. More in Whiskey Sour garnish.

Where Else the Egg White Turns Up

Difford's Rattlesnake is a 100-proof rye sour with three dashes of absinthe and ½ fl oz egg white; Morgenthaler's Amaretto Sour uses ½ oz with cask-proof bourbon; the Frisco Sour lists it as optional; and the Pisco Sour treats a whole egg white as standard. The rest of the ingredient set is in the ingredients guide, and the ryes that stand up to it are in the Bottle Library.

Frequently Asked Questions

Do you need egg white in a Whiskey Sour?

No. The IBA lists it as optional and Jerry Thomas's 1887 recipe has none. Egg white adds foam and a softer, fuller texture; PUNCH prefers the drink with it, and with it the drink is commonly called a Boston Sour.

How much egg white goes in a Whiskey Sour?

About ½ oz, roughly one small egg's white. PUNCH, Difford's and Jeffrey Morgenthaler all use ½ oz; the IBA's "few drops" is the minimum and gives only a thin lace of foam.

Is raw egg white in a cocktail safe?

The FDA warns that fresh eggs may carry Salmonella and advises pasteurized shell eggs or pasteurized egg products for raw-egg recipes, especially for children, older adults, pregnant women and the immunocompromised. Difford's specifies pasteurized egg white; Fee Foam and aquafaba are egg-free alternatives.

What is a dry shake?

Shaking the drink without ice first so the egg protein emulsifies into a stable foam, then adding ice and shaking again to chill. About ten seconds dry is Julie Reiner's guide. The reverse dry shake does the ice shake first, then shakes again without ice for a firmer head.

Can I use aquafaba instead of egg white?

Yes. Use about 1 oz of unsalted chickpea liquid per drink and dry shake it 10–12 seconds, longer than egg. It changes the flavor slightly; a dash of Angostura on the foam covers it.

What is the difference between a Whiskey Sour and a Boston Sour?

Egg white. Difford's puts it plainly: a Boston Sour is simply a Whiskey Sour with egg white, and it is usually served up. No reputable source explains the name.