Analysis of sparkling wine lees surface volatiles by optimized headspace solid-phase microextraction.

During sparkling wine aging, a narrow interaction is established between wine and lees of second fermentation, which remain in contact during long periods. In order to contribute to the knowledge on this interaction, volatile compounds retained by lees were described in this study. With this aim, solid phase microextraction (SPME) conditions were optimized in order to increase the sensibility for the analysis of volatiles sorbed by lees. This allowed proving the capacity of sparkling wine lees of second fermentation to retain several volatile compounds related with wine aroma: esters, aldehydes, norisoprenoids and terpenes known for their positive flavor impact were found in lees headspace. Most of them were previously described in "Cava" sparkling wine, while some compounds, such as the tentatively identified trimethyl tetrahydronaphthalenes, were not previously identified in yeasts or wine.