The Sour family is one of the oldest cocktail categories, described by Jerry Thomas in his 1862 book How to Mix Drinks. A Sour consists of a base spirit, water, sugar and a sour component, usually lemon. Some historians suggest that it is simply a scaled-down version of punch, whose serving formula is “one part sour, two parts sweet, three parts strong and four parts weak”.
The original recipe, however, dates back another century, to a time when travelling by sea took an age and was far from easy. Food often spoiled during voyages lasting several months, and water was not considered a particularly safe drink. Scurvy, malnutrition and seasickness were common problems for sailors until the arrival of English Vice Admiral Edward Vernon. Sailors commonly carried lemons and limes to prevent scurvy, and spirits as something safe to drink. Vernon began mixing a drink for his crew, but since he did not want a ship full of drunken companions, he diluted the spirit — usually rum — and added citrus juice to mask the alcoholic taste. Here we find the beginnings of today’s Sour. Sailors brought the idea ashore and gradually refined it into the form we know today. Several base spirits were used, but whiskey was a favourite, both for its availability and its popularity among Americans.
Recipe according to the IBA:
6 cl bourbon (or a base spirit of your choice)
4 cl lemon juice
2 cl simple syrup (1:1)
The white of one egg
One ingredient, however, is nowhere to be found in the original recipe: egg. No whites, no yolks, nothing. Egg whites were added later to give the cocktail a creamy, airy texture. They made the drink easier to enjoy and improved the overall impression in the glass. Many people today are concerned about using raw eggs. The original article describes the risk as very low, and suggests that combining free-range eggs with high-proof alcohol makes it minimal.
One well-known bartender once put his view of salmonella rather bluntly: “You have a much greater chance of choking on a peanut at the bar than of getting salmonella from our eggs.”
Now for the preparation! Whiskey works beautifully with lemon juice. Perhaps that is why most bartenders experiment with the sweet part of the cocktail. Different jams, syrups, honey and other sweeteners have all been tried, so do not hesitate to play around with this excellent drink yourself.
Our method for extra creaminess is to use the shaker three times: first with just the egg white to begin foaming, then a hard shake with ice, and finally a dry shake without ice. Cheers!