Abstract
Ethanol and fructose are important materials for the fuel and food markets; high fructose syrup production processes are still costly. The effect of inoculum medium composition on the production of fructose and ethanol from dates by selective fermentation was investigated. The addition of minerals improved the fructose content in the produced syrup and ethanol productivity. The addition of malt extract to the medium increased fructose yield from 94% to 97%, but decreased ethanol yield from 78% to 69%. The presence of peptone increased ethanol productivity and fructose fraction in sugar, while iron increased fructose yield to 100% in syrups with 371 g initial sugar/L. Compared to the commonly marketed 55% fructose, selective fermentation of date extract produced sugar syrups with at least 82% fructose and significant amounts of ethanol. The excellent fit by the new expanded model prediction to the experimental data makes them valuable tools for further process development or industrial applications.