Solid‐state cultivation of Chaetomium cellulolyticum on alkali‐pretreated sawdust

Solid‐state fermentations (78% initial moisture content) of alkali‐pretreated Eastern Hard Maple sawdust were conducted in tray and tumble fermentors using chaetomium cellulolyticum . Crude protein content of the solids rose from 0.9 to 11% in the tray fermentor and 8% in the tumble fermentor in 20 days. These levels were almost equal to those achieved in corresponding slurry‐state fermentations (1–5% (w/v)) of the same substrate. Specific growth rates were two to four times lower in the solid‐state fermentors but this was offset by their greater solids‐handling capacity: the rate of protein production per unit volume of fermentation mixture was comparable to that of the 5% (w/v) slurry and two to three times higher than that of the 1% (w/v) slurry.