Comprehensive oligosaccharide profiling of commercial almond milk, soy milk, and soy flour

Oligosaccharides are known for several bioactivities on health, however, in sensitive individuals, can cause in- testinal discomfort. This study aimed to investigate the oligosaccharide profiles in selected plant-based food products. A quantification method based on high-performance anion-exchange chromatography-pulsed amper- ometric detection was developed, validated, and used to measure major oligosaccharides. Additional low- abundant oligosaccharides and glycosides were characterized by liquid chromatography-tandem mass spec- trometry and glycosidases. The summed concentration of raffinose, stachyose, and verbascose ranged from 0.12-0.19 mg/g in almond milk, 3.6-6.4 mg/g in soy milk, and 74-77 and 4.8-57 mg/g in defatted and full-fat soy four. Over 80 different oligosaccharides were characterized. Novel compounds, 2,3-butanediol glycosides, were identified in almond milk. Low-abundant oligosaccharides represented 25 %, 6 %, and 10 % of total OS in almond milk, soy milk, and soy flour, respectively. The data here are useful to estimate oligosaccharide con- sumption from dietary intake and facilitate further studies on their bioactivity.