Assessment of volatile and sensory profiles between base and sparkling wines.

This paper focuses on the study of the volatile, olfactometric, and sensory composition of base wines and their corresponding sparkling wines (14-24 months aging) obtained at semi-industrial scale during three consecutive harvests. The sensory profile of sparkling wine is more complex than that of base wine, with toasty, lactic, sweet, and yeasty notes being described by the panelists and an even sharper increase of these tastes in the cava reserve. On the other hand, during the second fermentation and subsequent aging in contact with lees, some compounds such as acetate and ethyl esters decrease in amount while others such as norisoprenoids, acetal, diacetyl, and furans appear or increase over time. These volatile compounds could be responsible for the sensory profile depending on their notes, as determined by sniffing. The differences in volatile composition are responsible for the changes observed in the sensory profile of cava with respect to base wine.

Different commercial yeast strains affecting the volatile and sensory profile of cava base wine.

36 semi-industrial fermentations were carried out with 6 different yeast strains in order to assess differences in the wines' chemical and volatile profile. Two of the tested strains (Y3 and Y6) showed the fastest fermentation rates throughout 3 harvests and on 2 grape varieties. The wines fermented by three of the tested strains (Y5, Y3 and Y4) stand out for their high amounts of esters and possessed the highest fruity character. Wines from strains producing low amounts of esters and high concentrations of medium chain fatty acids, higher alcohols and six-carbon alcohols were the least appreciated at the sensory analysis. The data obtained in the present study show how the yeast strain quantitatively affects the final chemical and volatile composition of cava base wines and have repercussions on their sensory profile, independently of must variety and harvest year.

Volatile compounds of red and white wines by headspace--solid-phase microextraction using different fibers.

The behavior of four fibers [polydimethylsiloxane (PDMS), PDMS-divinylbenzene (DVB), carboxen (CAR)-PDMS, PDMS-DVB-CAR), is tested for the analysis of volatile compounds of white and red wine. The PDMS-DVB-CAR fiber is the most appropriate to obtain the most wide volatile profile of wines. The better extraction conditions are 40 min at 35 degrees C. Satisfactory data about the reproducibility and uptake are obtained for more than 40 volatile compounds of red and white wine.