Sugarcane molasses is the main source for ethanol production in India. Sweet sorghum
with its juicy stem containing sugars equivalent to that of sugarcane is a very good
alternative for bio-ethanol production to meet the energy needs of the country. Sweet
sorghum is drought resistant, water logging resistant and saline–alkaline tolerant. Growing
sweet sorghum for ethanol production is relatively easy and economical and ethanol
produced from sweet sorghum is eco-friendly. In view of this, it is important to identify
superior genotypes for ethanol production in terms of percent juice brix, juice extractability, total fermentable sugars, ethanol yield and fermentation efficiency. This paper
presents the study on the variability observed for the production of ethanol by various
sweet sorghum genotypes in a laboratory fermentor. Five Sweet Sorghum (Sorghum bicolor
L. Moench) genotypes were evaluated for ethanol production from stalk juice (Keller, SSV
84, Wray, NSSH 104 and BJ 248). Sweet sorghum juice differs from cane juice mainly in its
higher content of starch and aconitic acid. Data were collected for biomass yield; stalk
sugar yield and ethanol production in five genotypes. Maximum ethanol production of
9.0%w/v ethanol was obtained with Keller variety (20% sugar concentration was used), and
decreased for other genotypes. A distiller’s strain of Saccharomyces cerevisiae (gifted by
Seagram Distilleries Ltd.) was employed for fermentation. The fermentation efficiency (FE)
was 94.7% for this strain. High biomass of yeast was obtained with BJ 248 variety. When the
similar experiments were conducted with unsterile sweet sorghum juice (15% sugar
concentration) 6.47%w/v ethanol was produced.