There is a need for new approaches to isolate thermotolerant yeast strains that can be utilized for the efficient production of ethanol .The application of high-potential thermotolerant yeasts is a key factor for successful ethanol production at high temperatures The use of thermotolerant yeast is a vital to avoid the use of expensive cooling systems. In addition, avoids fermentation stops due to overheating, reducing the chance of infection and minimizes the volume of wastewater generated in the distilleries. Ninety strains of Saccharomyces cerevisiae were screened on sugar cane molasses medium for ethanol production .The higher fourteen strains were subjected to select the more osmotolerant strains on high gravity sugar cane molasses medium( 20% w/v fermentable sugars ), Thee promising osmotolerant were testing to select the faster fermentation rate .Three most patents were subjected to different temperature from 40oC to 55oC f0r different periods i.e 20 min to 18 hrs. The thermal tolerance of three selected strains were evaluated at temperatures between 28 to 44 °C. The high ethanol yield 11.42 % v/v, 11.55 % v/v and 11.64 at 40 °C were achieved by S. cerevisiaeF-96, S. cerevisiaeF-50and S. cerevisiae FE-403 respectively comparable to 9.65 % v/v,9.45 and 8.90 % v/v at 40°C achieved with the same strains respectively before heat shock treatment. Additionally, more than 96 % fermentable sugars utilization was achieved.
