Control of bacterial growth in carbonic maceration winemaking through yeast inoculation
Controlling the development of the bacterial population during the winemaking process is essential for obtaining correct wines. Carbonic Maceration (CM) wines are recognised as high-quality young wines. However, due to its particularities, CM winemaking implies a higher risk of bacterial growth: lower SO2 levels, enrichment of the must in nutrients, oxygen trapped between the clusters… Therefore, wines produced by CM have slightly higher volatile acidity values than those produced by the destemming/crushing method.
In this work, the bacteria present in CM vinifications under different yeast inoculation conditions were studied, in order to evaluate inoculation as a bacterial control strategy. For this purpose, three conditions were assayed: spontaneous fermentation, “pied de cuve”, and active dry yeast (ADY) inoculation.
The results showed that in the non-inoculated wines, a high bacterial population development was present in the tanks, and the finished wines showed high volatile acidity values, which did not occur in the inoculated vinifications. Thus, the control of the yeast population seems to be an effective tool to avoid bacterial alterations in CM vinifications.
Acknowledgements: This study has been financed from the Project RTI2018-096051-R-C31/C33 (MCIU/AEI/FEDER; UE).
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2) Santamaría P. et al (2022) Difficulties associated with small-scale production of carbonic maceration wines. Fermentation, 8, 27. https://doi.org/10.3390/fermentation8010027
Issue: ICGWS 2023
1 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
2 Departamento de Agricultura y Alimentación. Universidad de La Rioja, Spain