Aroma compounds and physical-chemical characterization of grapes and wines from Mount Etna “relic-jewels” vine genotypes

Abstract

In the last few decades, minor vine genotypes traditionally cultivated on the Mount Etna slopes, have attracted the interest of both researchers and vine growers, as they offer an interesting oenological profile. At the same time, they represent a genetic resource well adapted to the territories of origin, potentially able to face global warming. The research activity on some of these genotypes, referred to as “relic-jewels”, started in the mid-2000s, and in 2022 some wineries, located on three slopes of Mount Etna, were involved in assessing their agronomic potential.

In 2024, five red-berried genotypes (Barbarossa, Madama Nera, Terribile, Moscatella Nera, Minnella Nera) and three white-berried genotypes (Bianchetta, Madama Bianca, and Virdisi), were analyzed to assess their productive and oenological performance. Additionally, five traditional varieties (Nerello Mascalese, Nerello Cappuccio, Carricante, Grillo and Insolia) commonly cultivated on Mount Etna were used as controls. At harvest, for each genotype (relic-jewels and controls), the bunch and berry morphological traits, total soluble solids (TSS), titratable acidity, pH, anthocyanin, and polyphenol content were determined. Subsequently, the grapes underwent vinification and physicochemical analyses were carried out on the resulting wines. Particular attention was also given to the volatile aroma profile of the grapes and wines as they are one of the most important intrinsic factors influencing wine quality and consumer preferences. Headspace Solid-Phase Microextraction Gas Chromatography/Mass Spectrometry (HS-SPME-GC/MS) technique was used for the volatile aroma compounds analysis as it has a high sensitivity and allows a solvent-free analyte extraction minimizing artifact formation and allowing a direct correlation between volatile composition and consumer sensory perception. Multivariate statistical approaches were used to investigate the relationship between volatile aroma compounds in grapes and their corresponding wines.

Statistically significant differences were observed among the different genotypes. The physicochemical analysis highlighted medium-high sugar contents and moderate titratable acidity, with an important phenolic profile of grapes. The analysis of volatile aroma compounds revealed a diverse and complex aromatic profile of the grapes and the obtained wines, highlighting the presence of key varietal aroma compounds that contribute to distinctive sensory attributes. These findings underscore their potential for producing high-quality wines that are well accepted by consumers.

References

[1] Ferlito, F., Nicolosi, E., La Malfa, S., Cicala, A., & Gentile, A. (2018). Horti. Sci. 45(1).