Co-fermentation Approach of Fructose and Glucose to Ethanol from Chinese Elaeagnus angustifolia Fruit (EAF)

The soluble and fermentable carbohydrate contents was detected over 47% of glucose and fructose in Chinese Elaeagnus angustifolia fruit powder (EAF), being over 47 wt% sugar content more than that of grape. Ethanol was therefore fermented directly from EAF, and different submerged fermentation modes were comparatively employed to optimize ethanol harvest. The results indicated that glucose has certain competitive inhibition on fructose bio-utilization, as well as the EAF solid residue involved fermentation mode also hindered the fermented-ethanol titer. Pectinase addition and in situ hydrolysis seemed to assist somewhat the fermentation. The water-solute fermentation mode is preferable, and glucose and fructose components were completely consumed and converted to 80.96 g/L ethanol at 87.6% ethanol yield even under tannin and pectin inhibition. The fermentation result could provide some experimental data and an approach to not only new biomass resource explores of bioethanol and alcohol beverage production, but also the technological development on valorization commercials of EAF in global draught areas.