Impact of closure material on the chemical and sensory profiles of grappa during storage in bottle

The effects of different closure materials for stoppers were evaluated on the volatile and non-volatile composition and sensory profile of an Italian grappa (a fermented grape pomace brandy) stored in bottles for 12 months. With respect to technical stoppers, common micro-granulated cork stoppers increasingly absorbed the distillate over storage and released more intense non-volatile compounds determining the browning of grappa. Higher alcohols and esters were the main compounds contributing to the volatile profile of grappa and were correlated to pungent and floral/fruity aromas, respectively. Esters and alcohols from C3 to C8 (ethyl acetate, ethyl hexanoate, 3methyl-1-butanol acetate, 2-methyl-1-propanol, 3-methyl-1-butanol and 1-hexanol) decreased from three to six months of storage and further increased. Instead, the esters methyl decanoate, ethyl decanoate and ethyl dodecanoate increased from three to six months and then decreased. The sensory profile of grappa was also affected by the common micro-granulated cork stopper after one-year of storage in bottle as determined by the trained panel.