## 1 Introduction  
Spirit drinks are defined by the European regulation as beverages intended for human consumption with a minimum alcoholic strength of 15%. They possess particular organoleptic qualities and can be produced using specific methods, including distillation of fermented products and maceration of plant materials in agricultural ethyl alcohol [1]. Flavor compounds in distilled spirits present a large variety of chemical classes, such as esters, alcohols, fatty acids, carbonyls, sulfur compounds, terpenoids, volatile phenols, and heterocyclic compounds. Therefore, they present very diverse aromas. For instance, esters generally have a positive contribution to the flavor profile with fruity notes and heterocycles like furans are responsible for caramellic aromas. They are formed during different stages of the production process [2]. Raw materials containing carbohydrates subjected to alcoholic fermentation are a primary source of aromas. In addition to ethanol and carbon dioxide, the action of yeasts leads to the formation of volatile compounds that participate to the flavor profile. Distillation further enables the concentration of desirable organoleptic compounds as well as the reduction of unpleasant sulfur compounds [3]. Finally, during aging in oak casks, molecules such as whiskey lactones or volatile phenols are extracted from toasted wood. The participation of an individual compound to the flavor profile is not only related to its concentration, which can cover wide ranges in distilled spirits, but could also result of its odor perception threshold, defined as the lowest concentration than can be detected by smelling. Therefore, some substances found in liquors present at very low levels contribute significantly to the overall aroma profile of the beverage. Over the last few years, a large increase in the number of micro-distilleries has been observed. This type of distillery, which is not officially defined, can be described as a small-scale distillery that focuses on developing superior quality products rather than producing high quantities of spirit. Small scale production enables numerous variations at each stage of the process, facilitating the development of innovative fermentation, distillation and aging techniques and offering new aromas and flavors for distilled spirits. Micro-distilleries generally offer diverse types of liquors and several variations of each product [4]. Until recently, however, there has been a lack in chemical analysis of the distilled spirits produced, mostly because it requires efficient, reliable, and fast methods based on expensive apparatus and qualified staff. Consequently, the flavor singularity of their liquors is generally not demonstrated on a chemical point of view. Currently, the easiest way for small distilleries to analyze their product is to subcontract analyses of distilled spirits to dedicated laboratories. Occasional access to such analytical equipment is possible through agreements and scientific collaboration with academic research laboratories, for example, but some structures might prefer to carry out analysis of their spirits themselves. For those, analytical equipment is now becoming more affordable, a GC equipped with a flame ionization detector (FID) or a single quadrupole GC-MS being, for instance, in the range of 30,000 euros. Obviously, it implies hiring qualified personnel. In every case, proposing a versatile and easy to implement method applicable to different types of spirits, is relevant for private or public laboratories having to develop analytical methods to carry out such analyses and for small distilleries willing to perform analyses of their products on their own. Chemical analyses of distilled spirits have most frequently been carried out using gas chromatography because it enables the identification of a large number of analytes and can be coupled to various detectors [5]. When a classic chromatographic system is used (GC/FID or single quadrupole GC-MS), direct injection of the spirit enables to detect major components.