Fermentation Conditions and Sugar Metabolism of High-sugar Cane Juice

In this study,the fermentation conditions of high-sugar( 25 °BX) cane juice with a yeast strain having good resistance to alcohol and sugar were optimized by one-factor-at-a-time and orthogonal array design methods for maximizing alcohol production.The results indicate that the alcohol content in fermentation broth at the end of fermentation was up to 19.02% under the following optimal conditions: initial brix of fermentation liquor of 30 °BX,fermentation pH of 4.5,fermentation temperature of 30 ℃ and inoculation amount of 10%,which was much higher than that obtained by ordinary fermentation(10%-15%).Sugar utilization was also investigated at different brix levels during the fermentation process.When the brix was 30°BX,sugars could be fully utilized.However,fructose could not be utilized at the brix level of 35°BX.Moreover,neither fructose nor glucose could be utilized at the brix level of 40°BX.In fermentation broth,the osmotic pressure of sugars had a negative linear relationship with fermentation time and a negative linear relationship between sugar consumption rate and initial brix level was also observed.