PRODUCTION OF HIGH-PURITY FRUCTOLIGOSACCHARIDE

PURPOSE:To efficiently obtain a high-purity fructoligosaccharide without requiring removal of unnecessary substances by immobilizing glucose isomerase and fructofuranosidase on the same carrier and then bringing the resultant carrier into contact with a sucrose solution. CONSTITUTION:Glucose isomerase 3 capable of producing fructose (F) from glucose (G) and fructofuranosidase 4 capable of producing a fructoligosaccharide by transfer reaction are immobilized on a carrier 2 and arranged in a bioreactor 1. A solution of sucrose (GF) is then fed into the aforementioned bioreactor 1 to convert the glucose molecules (G) into fructose molecules (F) with the glucose isomerase 3. The activated fructose molecules (F) just after the formation thereof are bound to other molecules of the glucose (G) or sucrose (GF) with the fructofuranosidase 4 to produce fructoligosaccharides (GFF), (GFFF), etc. Nonoligosaccharide ingredients (G) and (GF), as necessary, are subsequently separated and removed by using a loose reverse osmosis membrane 5.