title: Yeast population dynamics during prefermentative cold soak of Cabernet Sauvignon and Malbec wines.
abstract: Prefermentative cold soak is a widely used technique in red wine production, but the impact on the development of native yeast species is hardly described. The aim of this work was to analyse the dynamics and diversity of yeast populations during prefermentative cold soak in red wines. Three different temperatures (14 ± 1 °C; 8 ± 1 °C and 2.5 ± 1 °C) were used for prefermentative cold soak in Cabernet Sauvignon and Malbec grape musts. Saccharomyces and non-Saccharomyces populations during cold soak and alcoholic fermentation were analysed. In addition, the impact on chemical and sensory properties of the wines was examined. Yeast dynamics during prefermentative cold soak were temperature dependent. At 14 ± 1 °C, the total yeast population progressively increased throughout the cold soak period. Conversely, at 2.5 ± 1 °C, the yeast populations maintained stable during the same period. Prefermentative cold soak conducted at 14±1°C favoured development of Hanseniospora uvarum and Candida zemplinina, whereas cold soak conducted at 8 ± 1 °C favoured growth of Saccharomyces cerevisiae. At 2.5 ± 1 °C, no changes in yeast species were recorded. Acidity and bitterness, two sensory descriptors, appear to be related to wines produced with prefermentative cold soak carried out at 14 ± 1 °C. This fact could be associated with the increase in non-Saccharomyces during the prefermentation stage. Our results emphasise the importance of the temperature as a determinant factor to allow an increase in non-Saccharomyces population during prefermentative cold soak and consequently to modify sensorial attributes of wines as well as their sensorial impact.
authors.affiliation: Instituto de Biotecnología, UNSJ, Av. San Martín 1109 (O), San Juan, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Argentina.
authors.forename: Y Paola
authors.initials: YP
authors.lastname: Maturano
authors.affiliation: Instituto de Biotecnología, UNSJ, Av. San Martín 1109 (O), San Juan, Argentina.
authors.forename: M Victoria
authors.initials: MV
authors.lastname: Mestre
authors.affiliation: Biotecnologia Enològica, Departament de Bioquímica i Biotecnologia, Facultat d' Enologia, Universitat Rovira i Virgili, Marcel·lı' Domingo s/n, Tarragona 43007, Spain.
authors.forename: Braulio
authors.initials: B
authors.lastname: Esteve-Zarzoso
authors.affiliation: Instituto de Biotecnología, UNSJ, Av. San Martín 1109 (O), San Juan, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Argentina.
authors.forename: María Cristina
authors.initials: MC
authors.lastname: Nally
authors.affiliation: Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Argentina; Estación Experimental Agropecuaria Mendoza, Instituto Nacional de Tecnología Agropecuaria (INTA), Argentina.
authors.forename: María Cecilia
authors.initials: MC
authors.lastname: Lerena
authors.affiliation: Instituto de Biotecnología, UNSJ, Av. San Martín 1109 (O), San Juan, Argentina.
authors.forename: María Eugenia
authors.initials: ME
authors.lastname: Toro
authors.affiliation: Instituto de Biotecnología, UNSJ, Av. San Martín 1109 (O), San Juan, Argentina.
authors.forename: Fabio
authors.initials: F
authors.lastname: Vazquez
authors.affiliation: Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Argentina; Estación Experimental Agropecuaria Mendoza, Instituto Nacional de Tecnología Agropecuaria (INTA), Argentina. Electronic address: combina.mariana@inta.gob.ar.
authors.forename: Mariana
authors.initials: M
authors.lastname: Combina
mesh_terms: D003080:Cold Temperature; D005285:Fermentation; D011157:Population Dynamics; D012440:Saccharomyces / Q000254:growth & development / Q000502:physiology; D013649:Taste; D027843:Vitis / Q000382:microbiology*; D014867:Water; D014920:Wine / Q000032:analysis / Q000382:microbiology*; D015003:Yeasts / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*
chemical_list: D014867:Water
keywords: Low temperature; Prefermentative cold soak; Red wine; Sensory analysis; Yeast