## 1 Introduction
The beneficial role of cork stoppers in still-wine aging is extensively studied. In this sense, some volatile and phenolic compounds can be transferred from cork to wine, contributing positively to wine aspects such as flavor, color or astringency development [10; 19]. The selection of the type of closure goes beyond the quality of the final product because it has also an effect on sustainability. Cork is a material obtained from the cork oak, and its extraction does not affect the viability of the tree--on the contrary, its use implies ecological and socio-economic roles [13; 20]. On the one hand, cork oak trees prevent soil degradation and desertification, contribute to biodiversity, and regulate the hydrological cycle [21; 22]. On the other hand, social and economic improvements are also related to cork-stopper production because cork extraction means there is an increase in jobs in rural areas and is combined with other jobs such as beekeeping. In the case of sparkling wine, the aromatic profile has been described previously for cava [23; 24; 25; 26], champagne [14; 27; 28], and Australian sparkling white wine [29]. This is also the case for ciders [30; 31] and beer [32; 33]. Overall, little is known about the impact of the type of closure on aroma evolution during second fermentation inside bottles [7; 34]. Ref. [7] proposed that the effect of cork as a closure is evident in the sensory attributes because samples closured with cork stoppers showed less autolytic character, a longer aftertaste, and visually more and smaller bubbles. Also, agglomerate cork stoppers help to preserve effervescence and aromas [18]. The characterization of aromatic compounds is an arduous task because the volatile fraction is composed of multiple substances with different physicochemical properties. Currently, there exist various devices for techniques such as headspace procedures. Headspace techniques are solvent-free procedures used in combination with GC-MS to isolate the aromatic compounds of several matrices according to their volatility [1]. This solventless preparation technique allows for the simultaneous extraction of several compounds. The HS-SPME method is the first headspace sampling technique developed by [35]. This is one of the commonly used methods for analyzing volatile and semi-volatile compounds in a wide range of matrices, such as wine [36; 37; 38; 39; 40]. On the other hand, the thermal desorption (TD) method stands out as an alternative to HP-SPME due to its capacity for a large sorbent phase and the use of a cryogenic focusing step to increase the sensitivity of the methodology [41]. The TD method has been widely studied because of its beneficial properties, such as its versatility or its high capacity of concentration of the selected compounds (up to 106) [42]. In TD, the first step is the concentration of headspace components in a desorption tube filled with the selected adsorbent. In the case of wine, Tenax (2,6-diphenyl-p-phenylene oxide) is an excellent adsorbent because of its low water- and ethanol-adsorbing capacities and its high adsorbing capacity for wine aromatic compounds [40]. Then, the charged tubes are thermally desorbed and intermediately trapped in a cryogenic trap, before being immediately injected into a gas chromatograph (GC-MS) after rapidly heating the filled trap. The detection power of this technique is enhanced with this trapping stage. It must be noted that this analysis is carried out with a compound that is thermally stable to avoid the decomposition process [41]. No studies have so far directly linked aroma compounds and the type of closure used for second fermentation and aging in bottle products. For this reason, a base wine in contact with yeast lees was closured using six types of closures with cork and screw-cap features for 94 months. The effect of the type of closure on the aroma profile of a sparkling wine obtained after second fermentation and aging in a bottle was studied.