A pretreated peel (at a concentration of 20 g/L) in 0.01 M phosphate buffer with pH 6 was used as the
SHF medium. The SHF experiments started with the inoculation of pineapple peel with the addition of the
enzyme solution (Cellulase, 100 FPU/mL) in 50 mL working volume for 0-96 h. Therefore, a filtersteriled
hydrolysate produce from pineapple peel under optimal condition was used as fermentation
medium with no nutrient supplementation. Afterward free and immobilized cell of S. cerevisiae and E.
aerogenes with a loading of 20% (w/v) was operated under anaerobic condition and a temperature
controlled at 30oC. The samples were collected every 6 h for 4 days (96 h) to determined sugar
concentration and the production of ethanol and hydrogen.