**Notes**

*Chemistry and Biochemistry of Winemaking, Wine Stabilization and Aging*

as a strain-dependent characteristic [62, 63, 66, 68, 69].

comparison to *S. cerevisiae*.

strain [68–70].

**3. Conclusion**

scarce.

The contribution from the aromatic point of view of *S. pombe* has been recently reported where it has been observed that it stands out mainly for producing fewer amounts of higher alcohols in comparison to *S. cerevisiae*, which could be attributed

Benito et al. [63] reported a lower production of isobutanol, 2-methyl-butanol, 3-methyl-butanol and 2-phenyl-ethanol in white wines by *S. pombe* in comparison to *S. cerevisiae*. Similar results have been reported by Mylona et al. [66] where, fermenting red must, they observed a decrease in 2-methyl-butanol, 3-methyl-butanol and isobutanol by *S. pombe* in comparison to *S. cerevisiae*. On the other hand, Chen et al. [69] observed that *S. pombe* possesses a special ability to produce more 2, 3-butanediol, which contributes to the fruity aroma described as banana to wines.

In the case of esters, a similar phenomenon occurs, observing that

*Schizosaccharomyces* shows a tendency to produce lower concentrations of esters in comparison to *S. cerevisiae.* It has been reported to produce lower concentrations of isoamyl acetate and 2-phenyl-ethyl acetate in comparison to *S. cerevisiae* [62]. Likewise, lower production of total esters was reported by Del Fresno et al. [68] in

Finally, *S. pombe* fermentations have been reported to show higher levels of acetoin in comparison to *S. cerevisiae* controls. Also, they are commonly associated with high levels of acetic acid. These levels might vary from strain to

There are many physiological studies on the contribution of non-*Saccharomyces* yeasts to the aromatic profile of wines. However, reports at the genetic level that explain the differences observed in these yeasts with respect to *S. cerevisiae* are

Despite the little information available, it is possible to establish that the differences in aromatic potential observed in non-*Saccharomyces* yeasts are mainly due to modifications in the Ehrlich pathway and the biosynthesis of acetate esters and

The identification of most of these biological mechanisms has been possible

Given the relevance of the contribution of non-*Saccharomyces* yeasts to the quality and typicity of wines and their impact on taste, more studies with genetic approaches that explain the metabolic diversity of these yeasts are required.

The authors thank Dr. Tania Zaviezo, Paula Reyes-Bravo and Dagoberto Silva for their support in writing this manuscript. Fondo Nacional de Desarrollo Científico

ethyl esters. These changes can be summarized as follows:

thanks to the use of massive sequencing technology (NGS).

b.Absence of paralogous genes

d.Modification of enzymatic activities

c.Gene duplications

**Acknowledgements**

a.Differences in the regulation of gene expression of these routes

**82**

**Figure 2** was created with BioRender.
