Linkage-resolved profiling of isomalto-oligosaccharides using porous graphitic carbon liquid chromatography–orbitrap tandem mass spectrometry
Journal
Food Chemistry
Journal Volume
507
Start Page
148278
ISSN
0308-8146
Date Issued
2026-04
Author(s)
Abstract
The digestibility and glycemic response of isomalto-oligosaccharides are determined by their glycosidic linkage and chain length. However, linkage-resolved profiling beyond tetrasaccharides remains limited. Herein, forty structures from disaccharides to hexasaccharides in eight commercial materials were characterized using porous graphitic carbon liquid chromatography–Orbitrap tandem mass spectrometry. Linkage profiles were dominated by α-1 → 6 and α-1 → 4, displaying a chain-length-dependent shift. Generally, α-1 → 4 linkages accounted for ∼10% of total linkages in disaccharides, rising to ∼80% in hexasaccharides. In one sample, α-1 → 4 linkages were 1.6-fold more abundant than α-1 → 6. With contents of 62.5–81.5%, no product met the European Food Safety Authority description for isomaltose plus trisaccharide–nonasaccharide content (≥90% dry basis). Even in products labeled “total isomalto-oligosaccharides ≥90% (dry basis),” α-1 → 6 linkages accounted for only ∼50% of glycosidic linkages. This suggests the need for linkage-resolved isomalto-oligosaccharide labeling frameworks that extend beyond total content claims to more precisely reflect the digestibility and glycemic impact.
Subjects
Dietary fiber labeling
Glycosidic linkage profiling
Isomalto-oligosaccharides
Orbitrap tandem mass spectrometry
Porous graphitic carbon liquid chromatography
Publisher
Elsevier BV
Description
Article number 148278
Type
journal article