Process for enzymatic preparation of cellooligosaccharides

A continuous process for preparing cellooligosaccharide from a cellulose-containing substance in an aqueous medium comprising the steps of, in a reaction vessel,

• reacting the cellulose in the aqueous medium with cellulase produced by a microorganism designated cellvibrio gilvus, to produce a saccharification solution including the cellooligosaccharide and the reaction products;
• continuously separating the saccharification solution from the cellulose to obtain the cellooligosaccharide;
• and
• continuously adding aqueous medium to the reaction vessel to replace separated saccharification solution, and wherein
• the reaction vessel is an ultrafiltration reactor and
• the continuous separation step comprises ultrafiltering the saccharification solution using a membrane having a fractional molecular weight of 1,000 to 20,000 and removing the filtered saccharification solution from the reactor.