It seems as if most of the cocktail world has been focused more on spirits and bitters than on the category of liqueurs. This is unfortunate, as liqueurs are not only such a key flavoring and balancing ingredient in so many cocktails but they can be such a key component in a customer’s experience, whether served as a cordial or as an ingredient in culinary dishes or desserts.
Liqueurs are defined in the U.S. as a spirit that contains not less than 2.5% sugar by weight and has been flavored with fruits, seeds, nuts, herbs, flowers, spices, or cream. Artificial coloring is allowed. Most liqueurs have lower alcohol content than spirits, averaging 15% to 30% alcohol by volume.
In the U.S., the term “liqueur” is synonymous with cordials and is derived from the Latin liquefacere, meaning to liquefy. It refers to the early Middle Ages monastic practice of extracting the essence of botanicals, which were added to base spirits and believed to have medicinal properties.
For example, Chartreuse is made through a complex process involving redistillation, infusion, and maceration of over 130 herbs and botanicals using a grape brandy base. The Italian Aurum or the better-known Bénédictine both have their origin in other monastic orders. It became the practice to serve liqueurs as digestifs, holding to their original almost medicinal purpose of aiding digestion; then they became a critical component in the barman’s trade, as well as in the chef’s or pastry chef’s repertoire of recipes.
The best way to understand the myriad of liqueurs available to bartenders and mixologists is to categorize them by sub-types, such as fruit-flavored (e.g., Curacao), seed (e.g., Kummel®), aniseed (e.g., Anisette) or nut-based (e.g., Frangelico®), floral-based (e.g., St. Germain®), herbal-based (e.g., Chartreuse®), cream-based (e.g., Bailey’s Irish Cream®), peel-based (e.g., Cointreau ®), or as fruit brandies (e.g., Maraschino ®). Another category that has been a stalwart presence in the Mediterranean is pastis, an anise or licorice-based liqueur derived from absinthe until its banishment in 1915. Absinthe has made a return to the cocktail world, with limits on the amount of the active wormwood component, thujone, it can contain. However, it is not technically a liqueur as it lacks the requisite sweetness and is therefore more accurately classed as a flavored liquor.
The source of the added flavoring compound determines the method of extraction to most effectively preserve the original aromatic profile. These methods include infusion, whereby the compound is steeped in a hot liquid to extract flavors; maceration, whereby the flavoring agent is immersed in a spirit to extract the aromatic compounds; percolation, in which the flavoring agents are placed in a container or basket and the base liquor is passed through them repeatedly until all flavors are extracted; redistillation, used mostly for seeds, citrus peels, and botanicals such as mint, and may be performed under a vacuum so the lower temperatures preserve the flavors; and cold compounding, in which essences or concentrates are added to base spirits, a method used for the least complex liqueurs.
Liqueurs are known as a generic product, such as a crème de menthe, or as a proprietary brand, such as Grand Marnier®, the latter representing a unique recipe or process or combination of processes to lend complexity. There are literally well over 200 liqueurs; such a wide range of choices provides restaurants and bartenders many opportunities to differentiate themselves. Whether served straight up as a digestif in a carefully-selected glass, or on shaved ice as a frappé, or as key ingredients to such classic cocktails as the Aviation, using maraschino liqueur and crème de violette, liqueurs are all too often overlooked by restaurateurs and mixologists who focus on top quality spirits but may fail to notice the impact of the liqueur used in their recipes, which merely shortchanges the customer’s potential experience.