Sweetness and sensory properties of commercial and novel oligosaccharides of prebiotic potential

This study investigates the sweetness properties and other sensory attributes of ten commercial and four novel prebiotics (4-galactosyl-kojibiose, lactulosucrose, lactosyl-oligofructosides and raffinosyl-oligofructosides) of high degree of purity and assesses the influence of their chemical structure features on sweetness. The impact of the type of glycosidic linkage by testing four sucrose isomers, as well as the monomer composition and degree of polymerization on sweetness properties were determined. Data from the sensory panel combined with principal component analysis (PCA) concludes that chain length was the most relevant factor in determining the sweetness potential of a carbohydrate. Thus, disaccharides had higher sweetness values than trisaccharides which, in turn, exhibited superior sweetness than mixtures of oligosaccharides having DP above 3. Furthermore, a weak non-significant trend indicated that the presence of a ketose sugar moiety led to higher sweetness. The novel prebiotics tested in this study had between 15 and 25% of relative sweetness, in line with other commercial prebiotics, and samples varied in their extent of off flavour. Therefore, these findings suggest a potential use for clean tasting prebiotics as partial sugar replacers, or in combination with high intensity sweeteners, to provide a well-balanced sweetness profile.