Nutritional and technological aspects of barley β-glucan enriched biscuits containing isomaltulose as sucrose replacer

The objective of this work was to evaluate the physicochemical, sensory and potential glycemic response properties of a biscuit (β-GB) containing barley β-glucan at 6% w/w, sufficient to satisfy the EFSA's health claims related to cholesterol lowering and fecal bulk increase, and isomaltulose as sweetener. The freshly prepared β-GB was softer (p < 0.05) than the control biscuit (formulated with sucrose and without β-glucan); differences in hardness between the two biscuit formulations diminished during storage. The glucose release kinetics, evaluated by an in vitro enzymic assay, showed that after 5 h of digestion, glucose release was significantly (p < 0.05) lower for the β-GB (16.4%) compared to the control (26.4%) or to several commercial products of similar composition, which were lacking the β-glucan as ingredient (22.7 – 33.7%). The extent of in vitro glucose released was negatively correlated (r = -0.72; p = 0.020) to the viscosity values of ‘physiological extracts’ enclosed in dialysis tubes after 5 h incubation, and to their total dietary fiber content (r = -0.79; p = 0.006) after 20 min of digestion. The fortified biscuits with β-glucan and isomaltulose were found to be satisfactory in terms of flavor, sweetness, and texture by a group of “diabetic individuals” who rated these products highly, with an average of 5.8, in a 7-point hedonic overall acceptability scale. The low extent of glucose released along with the sensory results suggested that isomaltulose containing biscuits fortified with β-glucans could simultaneously provide various health benefits and be highly acceptable by consumers with glucose metabolism disorders.