 Cellulose is not conventionally considered a β-glucan, as it is insoluble and does not exhibit the same physicochemical properties as other cereal or yeast β-glucans.Some β-glucan molecules have branching glucose side-chains attached to other positions on the main D-glucose chain, which branch off the β-glucan backbone.In addition, these side-chains can be attached to other types of molecules, like proteins, as in polysaccharide-K.