conditions. The reducing sugars concentrations were calculated
using a calibration curve and reading the absorbance of the samples
at 550 nm. The ethanol concentration was determined for all
fractions collected from distillation by the dichromate method
(Williams and Reese, 1950). This chemical oxidation method is
based on the complete oxidation of ethanol by dichromate in the
presence of sulfuric acid with the formation of acetic acid.