BRANCHED OLIGOSACCHARIDES CONCENTRATED BY YEAST FERMENTATION AND EFFECTIVENESS AS A LOW SWEETNESS HUMECTANT

A branched oligosaccharides (BOS) mixture was prepared from liquefied corn starch using Bacillus licheniformis maltogenic amylase (BLMA). A highly concentrated BOS was prepared by removing glucose and maltose t hrough yeast fermentation, which increased the BOS content. Water acti vity (a(w)) of bread went from 0.87 to 0.82 when 10% (w/w) or to 0.78 when 20% (w/w) BOS was added. BOS lowered a(w) more effectively as con centration of BOS increased. The water sorption isotherm of BOS was mu ch higher than that of sucrose at a(w), 0.1-0.8. BOS also prevented st arch retrogradation in bread, probably due to steric hinderance and to the state of water retained by BOS. Relative sweetness of BOS was app roximate to 17.5% of sucrose. The BOS mixture produced by BLMA might p rovide a new type humectant for foods that is low in sweetness and ret ards retrogradation.