3.2. Sweet sorghum grains: compositional analysis and enzymatic
activities
The starch content in the sorghum grains was 79% (dry mass),
which corresponds to 68% in wet mass. The protein, crude fiber,
crude fat and ash contents were 10.0, 1.4, 3.4 and 1.1%, respectively.
Enzyme activities for a-amylase at 90 C and glucoamylase at 55 C
were 494 U mL1 and 465 U mL1, respectively, which were
quantified using acetate buffer and soluble potato starch as a
substrate.
3.3. Sweet sorghum grains: kinetic profile of enzymatic hydrolysis
and fermentation
Enzymatic hydrolysis of sweet sorghum grains, performed under
the optimal conditions determined by Barcelos et al. [11],
resulted in a final sugar concentration of 250 g L1, which corresponds
to a hydrolysis conversion efficiency of 99% (Fig. 3).