Novel technique for saccharification of cassava fibrous waste for alcohol production.

A novel technique, involving the hydrolysis of starch present in cassava fibrous waste in shallow layers in stainlcss steel trays, is developed to facilitate the use of higher slurry concentrations. The use of slurry containing 30% solids. 4% sulphuric acid, 30 min saccharification time at 121°C resulted in the complete conversion of the starch into reducing sugars. The spent residue, after separation of the hydrolysate, contained about 24% of the total sugars formed and these were recovered to the extent of 90-94% by using a counter-current extraction technique. A large scale saccarification of a 75 kg batch gave 75 I pooled hydrolysate containing 15% reducing sugars. An overall process efficiency of 76.4% was observed with the fermentation of hydrolysate pooled with the counter-current extract for alcohol production. However, fermentation of the whole saccharified pulp without the separation of the hydrolysate and acid-enzyme hydrolysis of the waste gave lower efficiencies.