**Do Non-***Saccharomyces* **Yeasts Work Equally with Three Di**ff**erent Red Grape Varieties?**

#### **Rocío Escribano-Viana, Patrocinio Garijo, Isabel <sup>L</sup>ópez-Alfaro, Rosa <sup>L</sup>ópez, Pilar Santamaría, Ana Rosa Gutiérrez and Lucía González-Arenzana \***

ICVV, Instituto de Ciencias de la Vid y el Vino, Universidad de La Rioja, Gobierno de La Rioja, CSIC. Finca La Grajera, Ctra LO-20- salida, 13, 26071 Logroño, Spain; rocio.escribano@icvv.es (R.E.-V.); pgarijo@larioja.org (P.G.); isabel.lopez@unirioja.es (I.L.-A.); rosa.lopez@icvv.es (R.L.); psantamaria@larioja.org (P.S.); ana-rosa.gutierrez@unirioja.es (A.R.G.)

**\*** Correspondence: lucia.gonzalez@icvv.es; Tel.: +34-941894980

Received: 4 November 2019; Accepted: 27 December 2019; Published: 31 December 2019

**Abstract:** The present study aimed to investigate the oenological changes induced by non-*Saccharomyces* yeasts in three red grape varieties from the Rioja Qualified Designation of Origin. Pilot plants fermentation of three different varieties, were conducted following early inoculations with *Metschnikowia pulcherrima* and with mixed inoculum of *Lachancea thermotolerans*-*Torulaspora delbrueckii* from La Rioja and compared to a wine inoculated with *Saccharomyces cerevisiae*. The microbiological and physicochemical characteristics of vinifications were analysed. Results showed that most of the variations due to inoculation strategies were observed in Tempranillo just after the alcoholic fermentation, probably because of the better adaptation of the inocula to the must's oenological properties. Finally, after the malolactic fermentation the inoculation with the mix of *Lachancea thermotolerans* and *Torulaspora delbrueckii* caused more changes in Tempranillo and Grenache wines while the early inoculation with *Metschnikowia pulcherrima* had more effects on Grenache wines. Therefore, the study was aimed to identify the fermentation effects of each inoculation strategy by using different non-*Saccharomyces* yeasts and different grape varieties.

**Keywords:** *Metschnikowia pulcherrima*; *Lachancea thermotolerans*; *Torulaspora delbrueckii*; Grenache; Graciano
