Impact of Climatic Conditions on the Growth and Population Dynamics of Flor Yeasts in Biologically Aged Sherry Wines

INTRODUCTION

The biological aging of certain fortified wines from the D.O. Jerez/Xérès/Sherry is characterized by the development of a surface yeast biofilm known as velo de flor.

Among the most influential stress factors affecting flor yeast development are the thermohygrometric conditions within the aging cellars (Navia-Osorio et al., 2023).

This study examines three soleras of Fino wine to investigate the relationship between temperature and humidity variations and the yeast population dynamics and analytical composition of the wines aged in these areas.

MATERIALS AND METHODS

Temperature and humidity within the cellar were monitored by meteorological stations in three distinct zones. Additionally, an external environmental monitoring system was installed outside the building.

The population distribution of velo de flor yeasts in the three soleras was assessed using molecular biology techniques: PCR–ITS region of ribosomal DNA (Kurtzman et al., 2011) and multiplex microsatellite analysis (Vaudano et al., 2008).

The volatile composition of the wines was analyzed by gas chromatography (GC).

RESULTS

The results correlate the environmental thermohygrometric conditions and the development of the velo de flor. The architecture of the cellar allows for the identification of areas with more favorable climatic inertia for the development of the biological aging of Finos.