Taste Perception of Branched Maltooligosaccharides

Oral processing of starch generates linear and branched maltooligosaccharides (MOS). This study investigates the impact of branching and the degree of polymerization (DP) on MOS taste detection. Three branched MOS samples (A-C) were enzymatically prepared from gelatinized waxy corn starch and characterized using reducing-end assays, MALDI-TOF MS, β-amylase hydrolysis, and GC-MS linkage analysis. Samples A, B, and C had average DPs of 6, 10, and 18, respectively, with α-1,6 branch points comprising 9-13% of glycosidic bonds; linear MOS were negligible. In triangle tests, participants evaluated MOS samples and a maltose control at 75 mM, with and without lactisole, a sweet receptor inhibitor. All samples were detectable without lactisole (d' = 1.81-2.9; p < 0.05), but not with lactisole (d' = 0-0.61; p > 0.05). These findings demonstrate that α-1,6 branching enables MOS detection via the sweet receptor, not the putative "starchy" receptor, underscoring the critical role of glycosidic structure in carbohydrate taste perception.