SENSORY CHARACTERIZATION OF COGNAC EAUX-DE-VIE AGED IN BARRELS REPRESENTING DIFFERENT TOASTING PROCESS

Abstract

Cognac is an outstanding french wine spirit appreciated around the world and produced exclusively in the Nouvelle-Aquitaine region, and more precisely in the Cognac area. According to AOC regulations (Appellation D’origine Controlée), the spirit required at least 2 years of continuous ageing in oak barrels to be granted the title of Cognac. The oak wood will import color, structure and organoleptic complexity. The different steps during barrel-making process, such as seasoning and toasting, influence the above quality attributes in both wines and spirits. Barrel toasting is probably the most important step in barrel manufacturing, as it influences oak wood chemical composition, which is then likely to migrate into the wine and spirits during ageing, affecting their organoleptic properties. From a sensory point of view, no studies have been conducted focusing on the influence of barrel toasting on Cognac eaux-de-vie. Therefore, the aim of our study is to perform a sensory characterization of Cognac eaux-de-vie aged for 12 months in barrels representing different toasting levels. Eight eaux-de-vie aged in barrels with 8 different toastings were studied. The 8 toastings represented 4 different temperatures (low, medium, medium plus and high) and two toasting lengths for each temperature (one so-called “normal” and the other “slow”). Sensory analysis was carried out on these eaux-de-vie through several tests. First, a sor- ting test showed the differences between the samples and then training was carried out on previously chosen descriptors in order to build a sensory profile and perform a ranking test. The study was realised at an alcohol level of 40 % (v/v), which is the alcohol level of a commercial Cognac. The results showed that the eaux-de-vie are strongly impacted by the toasting of the barrel during the first year of ageing and it is possible to differenciate them according to the toasting used. Light barrel toasting results in significantly different eaux-de-vie from those aged in high-toast barrels. The latter tends to result in high quality eaux-de-vie. This study is a first step in the characterisation of Cognac eaux-de-vie aged in barrels made with different toastings and can lead to practical recommendations in order to obtain the ideal toasting temperatures that give the best olfactory and gustatory profiles in eaux-de-vie.