- Verbascose is a plant-derived oligosaccharide belonging to the raffinose family of oligosaccharides (RFOs). It is a pentasaccharide with the molecular formula C₃₀H₅₂O₂₆, composed of three galactose units, one glucose unit, and one fructose unit.
- Structurally, verbascose can be described as an extension of stachyose (galactose–galactose–glucose–fructose) with an additional galactose residue, resulting in galactose–galactose–galactose–glucose–fructose. Like other RFOs, verbascose is non-reducing, highly soluble in water, and accumulates predominantly in seeds, legumes, root vegetables, and certain leafy plants.
- In plants, verbascose functions as a storage and transport carbohydrate. Many higher plants, especially legumes, rely on raffinose-series oligosaccharides such as raffinose, stachyose, and verbascose to move sugars through the phloem instead of relying solely on sucrose. This adaptation offers several physiological advantages: RFOs are more stable during phloem transport, less susceptible to degradation by pathogens, and contribute to stress tolerance under drought, cold, and oxidative conditions. In seeds, verbascose and its related oligosaccharides accumulate during maturation and desiccation, protecting cellular membranes and proteins and enhancing seed longevity.
- From a nutritional standpoint, verbascose shares similar characteristics with raffinose and stachyose in being indigestible to humans and many animals due to the absence of the enzyme α-galactosidase, which is required to hydrolyze the α-1,6-galactosidic linkages. Consequently, verbascose passes undigested into the large intestine, where it is fermented by gut microbiota, producing gases such as hydrogen, carbon dioxide, and methane. This explains its association with flatulence and gastrointestinal discomfort after the consumption of beans, lentils, and other legumes rich in RFOs. At the same time, verbascose has prebiotic properties, as it promotes the growth of beneficial gut bacteria such as Bifidobacteria and Lactobacilli, thereby supporting digestive health and microbial balance.
- In applied contexts, verbascose and other RFOs are being studied for their potential as functional food ingredients. Their role as prebiotics offers opportunities in improving gut health, mineral absorption, and immune function. Plant breeders and food technologists are working on strategies to reduce RFO content in legumes—either by selective breeding or enzymatic processing—to minimize flatulence while preserving their nutritional and health-promoting properties. Additionally, research has suggested that verbascose-containing oligosaccharides may exhibit antioxidant, antidiabetic, and immunomodulatory effects, although further studies are needed to confirm these benefits.
