Simultaneous production of bioethanol and value-added D-psicose from Jerusalem artichoke (Helianthus tuberosus L.) tubers

In this study, the production of bioethanol and value added D-psicose from Jerusalem artichoke ( JA) was attempted by an enzymatic method. An enzyme mixture used for hydrolysis of 100 mg mL(-1) JA. The resulting concentrations of released D-fructose and D-glucose were measured at approximately 56 mg mL(-1) and 15 mg mL(-1), respectively. The D-psicose was epimerized from the JA hydrolyzate, and the conversion rate was calculated to be 32.1%. The residual fructose was further converted into ethanol at 18.0 g L-1 and the yield was approximately 72%. Bioethanol and D-psicose were separated by pervaporation. This is the first study to report simultaneous D-psicose production and bioethanol fermentation from JA.