The ethanol concentration was determined by gas chromatography (GC) on
a PerkinElmer autosystem XL Headspace using a FID detector and a column HPMS 30 m. The GC program was: 50◦C for 3 min; 10◦C/min, 100◦C for 1 min;
25◦C/min, 125◦C for 1 min; the injector and detector temperatures were 200 and
300◦C, respectively. Ethanol quantification was performed using a calibration curve
between 0.1% and 3.4%, v/v of ethanoThe statistical analysis of the results was performed applying a variance analysis
(ANOVA) to determine the difference between the averages and the test of Tuckey
to determine the homogenity of the variances between the groups.All the yeasts grew in the maintenance medium at 35 and
40◦C. Only two strains (IR2; IR2*) grew at 42◦C and no strain at
45◦C. The strains that grew at 40◦C in the maintenance medium
were incubated in the growth medium and the biomass and
ethanol production were evaluated at 24 h at 35, 40, 42 and
45◦C: