Production of alcohol from raw wheat flour by Amyloglucosidase and Saccharomyces cerevisiae

Ethanol production, by a simultaneous saccharification and fermentation process from raw wheat flour, has been performed by Saccharomyces cerevisiae and a low level of amyloglucosidase enzyme. The fermentation time was about 60 h after a 6 h pre-saccharification, with an amyloglucosidase (AMG) level of 270 AGU · kg−1 starch, but only 31 h with a simultaneous saccharification fermentation process (SSF). When an AMG level of 540 AGU · kg−1 starch was used, the time decreased to 21 h, giving an ethanol concentration of 67 g · l−1. Sugar composition of the wort after the liquefaction may be responsible of the difference between these two process. Maltose, a fermentable sugar, was produced in high concentration during the liquefaction, allowing a shorter process period, counteracting the effect of the slow starch hydrolysis at 35°C (SSF temperature).