Metschnikowia pulcherrima (Mp) is a ubiquitous yeast that frequently appears in spontaneous fermentations. The current interest in Mp is supported by the expression of many extracellular activities, some of which enhance the release of varietal aromatic compounds. The low fermentative power of Mp makes necessary the sequential or mixed use with Saccharomyces cerevisiae (Sc) to completely ferment grape musts. Mp has a respiratory metabolism that can help to lower ethanol content when used under aerobic conditions. Also, Mp shows good compatibility with Sc in producing a low-to-moderate global volatile acidity and, with suitable strains, a reduced level of H₂S. The excretion of pulcherrimin gives Mp some competitive advantages over other non-Saccharomyces yeasts as well as providing some antifungal properties.

Lachancea (kluyveromyces) thermotolerans is a ubiquitous yeast that can be naturally found in grapes but also in other habitats as soil, insects and plants, extensively distributed around the world. In a 3-day culture, it shows spherical to ellipsoidal morphology appearing in single, paired cells or short clusters. It is a teleomorph yeast with 1–4 spherical ascospores and it is characterized by a low production of volatile acidity that helps to control global acetic acid levels in mixed or sequential inoculations with either S. cerevisiae or other non-Saccharomyces species. It has a medium fermentative power, so it must be used in sequential or mixed inoculations with S. cerevisiae to get dry wines. It shows a high production of lactic acid able to affect strongly wine pH, sometimes decreasing wine pH by 0.5 units or more during fermentation. Most of the acidification is produced at the beginning of fermentation facilitating the effect in sequential fermentations because it is more competitive at low alcoholic degree. This application is especially useful in warm areas affected by climatic change. pH reduction is produced in a natural way during fermentation and prevents the addition of tartaric acid, that produces tartrate precipitations, or the use of cation exchangers resins highly efficient reducing pH but with undesirable effects on wine quality. Production of lactic acid is done from sugars thus reducing slightly the alcoholic degree, especially in strains with high production of lactic acid. Also, an improvement in the production of 2-phenylethanol and glycerol has been described.

Freshness, although it is a concept difficult to define in wines, can be understood as a combination of different circumstances. Organolepticwise, bluish red, floral and fruity, more acidic and full-bodied wines, are perceived as younger and fresher by consumers. In traditional winemaking processes, these attributes are hard to boost if no other technology or biotechnology is involved. In this regard, the right selection of yeast strains plays an important role in meeting these parameters and obtaining wines with fresher profiles. Another approach in getting fresh wines is through the use of novel non-thermal technologies during winemaking. Herein, the contributions of non-Saccharomyces yeasts and emerging technologies to these parameters are reviewed and discussed.