Effects of the synergy between T. delbrueckii and S. cerevisiae in the winemaking of traditional cultivars from southeastern Italy

Abstract

The combination of Torulaspora delbrueckii and Saccharomyces cerevisiae in co-inoculation and sequential inoculation in winemaking was investigated as an innovative strategy to increase the aromatic profile of wines like Verdeca and Nero di Troia wines, two traditional varieties from south-eastern Italy (Apulia Region). The study was conducted on a pilot scale with the objective of evaluating the effect of different inoculation methods on fermentation kinetics, enological parameters and sensory quality of the wines produced. The results show that sequential inoculation with T. delbrueckii produced less volatile acidity and positively modulated sugar metabolism, promoting a more balanced fermentation.  Analysis of the volatile profile of the wines produced in this study revealed particularly interesting results, with significant sensory differentiation between the samples. Among these, a marked increase in ethyl esters derived from saturated and unsaturated fatty acids was observed in the samples obtained through sequential inoculation with S. cerevisiae and T. delbrueckii. These compounds played a key role in the aromatic characterisation of the wines, contributing significantly to the distinction between the different fermentation conditions analysed. The increased presence of these esters, known for their positive impact on wine sensory characteristics, suggests that the combined use of these yeasts may represent an effective approach to modulate the aromatic profile and improve the olfactory complexity of the final product.

Sensory analysis showed a significant impact on aromatic complexity, with an enhancement of fruity notes, particularly in rosé wines made from Nero di Troia. In these samples, fermentations with T. delbrueckii intensified the desirable red fruit characters, giving greater freshness and taste-olfactory persistence. These results confirm the potential of non-Saccharomyces yeasts in the vinification of Apulian native varieties, offering new opportunities to enhance territorial identity and improve the sensory quality of these wines. The integration of T. delbrueckii in oenological protocols could represent an effective strategy to respond to the needs of a market increasingly oriented towards distinctive, high-quality products.