Juniper is the essence of gin, in both senses of the word: it is the defining feature and the primary flavoring agent. Gin has been with us for about 300 years, yet non-alcoholic beverages flavored with juniper go back thousands of years. The early use of juniper in beverages, typically in combination with other herbs, fruit, and sweeteners, had two aims. First, juniper’s strong flavor improved, or at least overshadowed, poor-tasting base liquids. Additionally, infusions were a convenient way to deliver the essential compounds of juniper, which were perceived to have medicinal benefits.
Over the centuries, juniper extract has been thought to cure headaches and toothaches, calm angry kidneys and bowels, aid the bladder, slow the growth of tumors, inhibit seizures, and soothe back pain. It has been used to both prevent and terminate pregnancy. Juniper has been employed as insect repellent and, in the Middle Ages, to ward off plague. Alas, none of these claims are supported by science. Modern research does indicate that certain species of juniper have anti-bacterial properties, but realistically, juniper’s best application is the one dearest to us: gin.
No historical timeline for the development and evolution of gin can be completely authoritative. Benedictine monks in southern Italy in the 10th century were probably the first to combine juniper and a distilled spirit. This followed pioneering work in distillation by two Arab alchemists who evangelized spirits for maximizing extraction of medically beneficial compounds from herbs and roots. One of those scholars, Jabir Ibn Hayyan, also created the first alembic still. It is widely believed that genever was created first in the area which is now Belgium, between the 13th and 15th centuries. Over time, that juniper infusion became a drink of pleasure, not just medicine.
Additional details on the history of gin will be discussed later in this article, but for a more in-depth discussion, also see Mark Ridgwell’s GuildSomm article “Gin: The Perfect Storm of Tradition and Innovation."
This article aims to give a broad overview of the spirit, covering methods of production, styles of gin, and the classic cocktails that you should know well.
While there are many styles of gin production and almost countless botanicals added for balance, flavor, and complexity, juniper alone is very complex. There are at least 67 species of juniper, though only a few are food safe and suitable for gin. EU regulations sanction just two for gin production: Juniperus communis L. and Juniperus oxicedrus L. (Note that some species of juniper are very poisonous. If you make gin at home, don’t forage for your juniper unless you are with an expert!)
Juniper berries have more than 100 volatile compounds. The character of those compounds varies substantially between species, growing regions, and even fresh versus dried berries. Ripeness of the berries and the method and temperature of extraction also create substantial variation.
There are a variety of ways juniper and other botanicals are introduced to the spirit, all with pros and cons. The methods differ in efficiency of extraction and the tone of flavors they produce. Yet the final product is not significantly impacted by the method; rather, the recipe and process are most affected. Regardless of method, the EU stipulates that the dominant flavor must be derived from juniper berries.
Relatively few gin producers create their own neutral spirit. That type of distilling requires considerable space, equipment, additional steps, and disciplines. And, since the spirit is supposed to be neutral anyway, most producers are happy to purchase it from a reputable supplier.
Botanicals can simply steep in the spirit, before or after a final distillation. This, however, does not produce gin as defined by the EU regulations, but rather a “juniper-flavored spirit beverage.”
Botanicals are added to the neutral spirit before distillation. Sipsmith prides itself on using only a single co-distillation for each batch. St. George Spirits uses this method as well as the carter-head still, described below.
Extremely intense botanical spirits are created by introducing the botanicals, together or separately, to a small amount of neutral alcohol. This product is then blended with a much larger amount of spirit to create the final product. The concentrate can be made using any of the other methods listed here. This method increases the capacity and scheduling flexibility of a distiller. Used by craft distillers and large producers alike, it is by far the most common method because it is efficient and less prone to variation.
Alcohol boils at a lower temperature under vacuum. The character of volatile compounds in many botanicals is different at lower temperatures, so this method gives the distiller different notes with which to work. Though they do not use it for production, Dunnet Bay employs a small vacuum distiller for research and development.
Botanicals are held in a large perforated basket or pot. Spirit vapors exiting at the top of the main still pass through the basket prior to condensing. St. George Spirits uses the carter-head still in addition to co-distillation, as mentioned above. They determine which of these methods to use based on the character of the specific botanical being infused, considering flavor, how its essence will be best extracted, and how sensitive it is to heat.
Scotland’s Caorunn has the only working Copper Berry Chamber in the gin business. This chamber was created for the perfume industry. It’s similar to a Carter-head but, instead of all the botanicals being placed in a single pot, they are placed in thin layers on multiple, perforated trays within a large chamber. The ensures more even and thorough extraction.
Technically, genever isn’t gin. Also known as jenever, genièvre, Hollands, and Dutch Gin, genever translates to “juniper” and is the spirit which begat gin. Unlike gin, the base of which is a neutral spirit made from anything, a significant part of genever’s base spirit must be from malted grain.
The exact year of genever’s creation is not known. It evolved from brandy and unadulterated grain spirits sometime in 13th-to-16th-century Belgium, in part because of juniper’s supposed medicinal value. Demand increased dramatically during the plague years, as juniper was thought to ward off that disease. At some point during that period, people began drinking genever for pleasure as well.
The age of exploration drove the next phase of genever’s expansion. In hope of preventing scurvy and other diseases, the Dutch East India Company, a global enterprise with a massive fleet, took genever wherever it went. Even after the collapse of the Dutch East India Company in 1799, genever continued to grow in popularity. It had become a spirit of choice in England and the United States. Production didn’t peak until late in the 19th century.
There are three main styles of genever: oude (“old”), jonge (“young”), and korenwijn (“corn wine”). The lightest is jonge genever, a “younger” style developed in the early 1900s. It must contain less than 15% malted spirits and less than 10 grams per liter of sugar. This contrasts with oude genever, which must have more than 15% malted spirits and less than 20 grams per liter of sugar. Korenwijn raises the bar even further. It must be 51% to 70% malted spirit, with less than 20 grams per liter of sugar.
While there are genever-style products made in several countries, the term is geographically protected. Only spirits made in Belgium, the Netherlands, Germany, and France (or portions thereof) can be labeled with the term. There are 11 genever-certified regions.
Traditional producers still popular today are Bols and De Kuyper, both in Holland. Perhaps the most classic genever cocktail is the John Collins. Genever can also be substituted for gin, or even whisky, in many recipes from the Negroni to the Old Fashioned. In the Netherlands, it is often served straight, either freezing cold in a shot glass or at room temperature with a beer chaser.
The etymology of “Old Tom” is a matter of debate but, regardless of origin, the name was synonymous with gin, especially in Britain, for nearly a century starting in the mid-18th century. Both drier and lighter than genever, Old Tom was sweetened at the distillery to hide off-flavors resulting from the relatively primitive distilling techniques of the day.
Initially, the base spirit was heavy with malt character and quite sweet. The invention of the Coffey still around 1830 allowed production of more refined base spirits with cleaner, more neutral aromas and flavors. Added sugar was no longer a necessity. This gave rise to drier Old Tom that highlighted botanicals more clearly.
As the 19th century progressed, consumer taste moved increasingly to dry gin. Eventually, London Dry almost entirely displaced Old Tom in the glasses of gin drinkers. But because Old Tom was called for by name in such cocktail classics as the Martinez and Tom Collins, a couple of producers remained, albeit with a minimal share of the overall market.
In the past decade, interest in cocktail history has spawned a small Old Tom revival. However, lack of definitive recipes and Old Tom’s evolution means there’s no consensus on historical authenticity. Some contemporary products, like Hayman’s and Hernö, differ from “regular” gin solely in their distinctly elevated sweetness. Others, such as Ransom and Greenhook Ginsmiths, are heavier, pot-distilled spirits, colored to both eye and nose by barrel aging. All modern Old Toms use a much cleaner spirit than would have been available for the original product.
Despite its name and otherwise strict legal requirements, London Gin has no geographical restrictions. The word “dry” is optional but has import when used, distinguishing the gin from sweeter styles. By regulation, sugar content in London Dry Gin must be below 0.1 grams per liter.
London Gin cannot include coloring or artificial flavors. Neither can any flavors be added after the distillation process. Minimum allowable alcohol is 37.5% (40% in the US).
Production methods are more flexible. Various types of stills can be employed. Botanical character can come through co-distillation, alcohol steam infusion, or blending with separately distilled botanical concentrate. That said, juniper flavoring must be achieved through distillation, not maceration.
The aim for most London Dry Gins is balance and the ability to work in most any classic gin drink. While London Dry Gin is much drier than genever or Old Tom, it is also more botanical. Good examples are produced on both the industrial and craft levels.
Plymouth Gin used to be a protected geographical indication (PGI). Historically, distillers had to be based in Plymouth, England, to use the name. However, there’s only one distillery left in Plymouth: Black Friars, which makes the Plymouth brand. Its owner, Pernod Ricard, recently allowed the PGI to lapse, believing they would benefit from growth of the “Plymouth” category more than from continued exclusivity.
The success and eventual fame of Plymouth Gin arose in the 19th century from local distilleries’ contracts with the British navy, for whom the city was a major port. It was in Plymouth that “Navy Gin” was born. As the PGI was applicable to any gin produced in Plymouth, historically, there wasn't a style associated with it per se. That said, since it was the navy contract that really put Plymouth on the map, the Plymouth Navy Strength Gin is probably the most iconic example. It comes in at 57% alcohol, compared to 41% for the Plymouth Original Gin. Both are made with the same seven botanicals, though the ratios may differ.
Navy Strength Gin has a higher ABV than standard gin, with a minimum of 50% as opposed to 37%. In the 18th century, law required that the British navy have gin on every ship due to its believed health benefits and its usefulness in delivering other medicinal substances, such as quinine, and purifying drinking water.
But there was a problem. Unscrupulous producers would sell the Navy watered-down gin and, since the spirit was white (clear), this was hard to detect. As the story goes, the Navy realized that if gin with alcohol of 57% or higher spilled onto gunpowder, which was typically stored near the gin, the gunpowder would ignite. At lower alcohol percentages, gin acted like water and the gunpowder would fizzle. So, the gunpowder test became proof of alcohol content and spawned a term of measurement. Spirits at 57% were dubbed 100 degrees proof.
Gin aged in barrels has existed for centuries, but using barrels with the intention of affecting a gin’s character is, with very few exceptions, a 21st-century phenomenon. In the old days, barrels were simply the best way to store and transport gin. In fact, until the British 1861 Single Bottle Act, it wasn’t even legal for British resellers to sell wine or spirits by the bottle for takeaway.
Today, producers are aging gin for varying amounts of time in new barrels, old barrels, or barrels previously used for whisky or wine. Citadelle Réserve Gin uses a solera system!
US law prohibits use of the term “aged gin” on gin bottles as well as listing the duration of aging. Some gin producers get around this by referring to their gin as “yellow.” But beware: not all yellow gin is barrel aged—it may be colored through additives. As for aging length, some distillers borrow terms like añejo.
Aging and barrel influence can have a dramatic effect on gin, meaning that aged gins may not substitute well in cocktails. Given how many different aging options there are, trial and error—or producer recommendations—are necessary. Alternately, use the aged gin in place of a whisky.
Sloe gin is very different from other gins. It’s a sweetened fruit liqueur made by macerating sloe berries, or blackthorn, in a gin base. The fruit is small and, if frozen then thawed, tastes of damson plum.
Sloe gin used to be a homemade concoction. Later, high-volume, low-price producers sold unappealing versions that used neutral spirits and different fruit or artificial flavors. Fortunately, there are now artisanal producers making very good sloe gin. They are fine enough to sip on their own or diluted with soda on ice.
Sloe gin is typically much lower in alcohol than standard gin and carries at least 2.5% sugar. There are specific cocktails designed for sloe gin, but it can also be substituted for other fruit liqueurs, such as maraschino or Chambord, or slipped in as an added ingredient. Sipsmith recommends theirs in a Negroni with equal parts gin, Campari, sweet vermouth, and sloe gin.
Gin’s simple definition allows tremendous latitude for creativity. The craft distilling movement and new technologies for micro-distillation have further unleashed innovation. Most new expressions fall into one or more basic categories.
Traditional gin is made with a neutral spirit. Using a base with more character makes a big difference.
With its focus on botanicals rather than spirit or wood, gin is a tabula rasa for local flavors.
Gin must be flavored with juniper, but juniper does not have to be the dominant flavor. Some gins pick one other flavoring agent and play it up.
Gin is an extremely versatile spirit. The range of styles, botanical accents, alcohol levels, and, usually, lack of barrel aging, let it lead or complement in a mixed drink. When evaluating character and fitness for cocktails, it’s best to sample the gin neat at room temperature, then again with a dash of water or an ice cube.
After that, there are three essential cocktails. Each has many variants, substituting one ingredient or another, changing garnishes, or making them “dry” by increasing the proportion of gin.
The Gin and Tonic dates to Britain’s colonial days in India. In 1870, tonic became a delivery medium for quinine, which helps prevent malaria, one of the leading killers in India at the time.
Today, inclusion of quinine in tonic is token. Tonic water simply dilutes and adds touches of sweetness, bitterness, and flavor. Mixologists add garnishes that highlight or complement the botanical accents of the gin. Lemon or lime are classic, but other fruits, juniper berries, flowers, and herbs are regularly used.
Caorunn, a lovely and balanced craft gin from the Speyside region of Scotland, includes a local apple, Coul Blush, among their botanicals. At the distillery, their Gin and Tonic features a slice of Coul Blush. It’s hard to find elsewhere, so try Gala apples instead for a very refreshing drink.
Martinis originated in the late 19th century. Though the origin is murky, many believe it started out with relatively sweet gin, Old Tom, and a large quantity of vermouth. Over the years, the gin became drier and the amount of vermouth decreased.
During Prohibition, with plentiful but poor quality gin, the ratio was 2:1. Now 6:1 is the standard, and some people prefer 10:1. That said, the craft movement is improving vermouth, making it more welcome in martinis.
Regardless of the exact ratio, gin is relatively undiluted, the feature attraction in martinis. Gin choice is crucial and based on the drinker’s preference in botanicals and balance.
The third star among gin-based cocktails today is the Negroni. Created in 1919, it has gained significant traction in recent years. It is a bold, bitter cocktail that teams gin with Campari and sweet vermouth. A classic Negroni is an equal parts cocktail, but many drinkers prefer a 2:1:1 ratio, with gin the larger portion.
How well a particular gin works will depend on ratios, which sweet vermouth is used, and the drinker’s preference. Are they ordering a Negroni because they like gin, or because they want it hidden?
Gin is a key aspect of any cocktail program. An understanding of production, styles, and basic history is crucial for any beverage professional. Both the lore of gin and the liquid itself are lively and memorable, offering plenty of opportunities to delight guests with varied selection, inspired cocktails, and amusing anecdotes.
Distiller Magazine, a quarterly published by the American Distilling Institute. Also online.
Knoll, Aaron. Gin: The Art and Craft of the Artisan Revival. London: Jacqui Small, 2015.
Miller, Anistatia, and Jared Brown. Spirituous Journey: A History of Drink, Book One. London: Jared Brown, 2009.
Miller, Anistatia, and Jared Brown. Spirituous Journey: A History of Drink, Book Two. London: Jared Brown, 2010.
Solmonson, Lesley Jacobs. Gin: A Global History. London: Reaktion Books, 2012.
Teacher, Matt. The Spirit of Gin: A Stirring Miscellany of the New Gin Revival. Kennebunkport, Cider Mill Press, 2104.
Excellent work Fred!!!