| Abstract
| - The aim of this work was to study the survival of yeast cells exposed to a combination of thermal andosmotic treatments, as occurs during drying processes, and assess associated changes in fluidity ofthe plasma membrane, which have been studied previously in this laboratory. Cells that weremaintained at a nonlethal dehydration temperature (5 or 30 °C) were rapidly dehydrated up to 120MPa, and then thermal stress was suddenly applied between 5 and 30 °C. Cell viability was measuredafter a return to initial conditions (i.e., 1.38 MPa and 25 °C). Results showed that the viability ofyeast cells exposed to identical combined thermal and osmotic treatments was dependent on thechronology of the stress application. Finally, the temperature at which the dehydration was conducted,up to 120 MPa, appeared to be the main factor involved in cell survival and could be related tofluidity variations of the plasma membrane. Keywords: Saccharomyces cerevisiae; osmotic pressure; temperature; viability; plasma membranephase; fluorescence anisotropy
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