Craft distilling has seen a surge of creative growth in the last decade, and gin is among the main spirit categories experiencing this boom. Gin production relies heavily on juniper and other botanicals to create the category’s signature flavors. There are two basic methods used to make gin: There’s compounded gin, which is made by soaking raw botanicals in a high-proof base spirit. And then there is distilled gin, which is far costlier and labor intensive to produce, but is the primary method for making the highest quality, most flavorful gins.
Most modern gin production starts with concentrated ethanol as the base spirit. These base alcohol ingredients usually come from grain, but some may also be produced using grapes or molasses. The finest gins involve a purification step of redistillation — or rectification — of the base alcohol. The majority of gin distillers purchase their neutral base alcohol from larger suppliers, rather than making it in-house, and then they may rectify it to meet the quality demands of a particular product.
Apart from ethanol and water, the primary botanical used to create the predominant flavor of gin is juniper. It’s no exaggeration to say that ethanol and juniper work together magically. Ethanol draws out a very specific set of oils from within the juniper berries —mainly monoterpenes and sesquiterpenes — which are among a suite of flavor molecules found in juniper berries: α-pinene (piney), sabinene (earthy, spicy), limonene (citrus), borneol (woody), β-myrcene (musty, spicy), p-cymene (pungent, citrus), camphene (woody), cineole (mint), terpinene (woody) and terpinen-4-ol (nutmeg), farnesene (floral), cadinene (woody), and caryophyllene (spicy). The flavor molecules and their proportions vary between different varieties of juniper, and where they grow. Distillers often have preferred botanical suppliers that source their botanicals from specific regions. Most juniper used in gin production comes from Italy.
Whereas juniper forms the basis of most gins, a wide range of other botanicals — angelica, orris root, lemon, coriander, cardamom, to name just a few — help to fill out the overall flavor profile of a fine gin. The taste of the end product, however, is not just the sum of its botanical complement: Flavor molecules interact in different and often unpredictable ways when a gin is mixed in a cocktail, all of which is a product of the unique components used to make a gin. Two separate gins, each made with juniper as the predominant flavor ingredient, could differ hugely depending on the other botanicals used.
Mixers also play a huge role in the flavor experience of gin. The combination of various cocktail ingredients can create unique flavors that are very different from the gin itself. This is why careful attention to every step of gin production is so crucial. An award-winning gin recipe is ultimately the result of far more than just the initial flavors derived from the primary botanical ingredients.
Selecting the right botanicals in the correct ratios is only one important variable in gin production. Whether a recipe involves maceration (soaking) or using a gin basket (vapor extraction), production methods have a huge impact on the final taste of the gin.
The shape of the still can also affect the flavor. The amount of liquid spirit that condenses and drains back into the kettle — called reflux— during the distillation process varies widely among stills of different shapes and configurations. Low reflux stills tend to be shorter, allowing heavier oils to carry over quickly. A taller still makes a more pure but less flavorful spirit due to repeated condensation cycles that concentrate the alcohol at the expense of losing more dense flavor molecules.
Collecting the Distillate
The taste and smell of the gin distillate changes quite noticeably over the course of a run, which means a gin distiller must pay close attention throughout the process. This is one of the most exciting things about making gin — different flavors emerge and evolve throughout the run, which gives the distiller the power to precisely shape the final flavor profile.
Distillers may blend distillates from different runs to help even out flavor consistency. Quality control is always subjective — it requires careful tasting and nosing for aromas. Some distilleries may add trace amounts of sugar or other adjuncts to shape the overall taste experience, but adjustments of that sort are generally frowned upon. Finally, water is added to bring the distillate to bottling proof, and the gin is packaged and made ready for the bar or store shelf.