Publisher Summary This chapter discusses polyfructosans and difructose anhydrides. Polyfructosans are prepared by enzymic action on sucrose. The different types of polyfructosans are insulin, levans, asparagosins, sinistrin, graminin, phlein, poan, secalin, triticin, and irisin. Inulin can be prepared from dahlia tubers, in somewhat lower yield from chicory, and in much lower yield from Jerusalem artichokes. Difructose anhydrides include diheterolevulosan, difructose anhydride I, difructose anhydride II, difructose anhydride III. Difructose anhydrides I, II, and III have been isolated from the nonreducing residue that remains after the removal of D-fructose and D-glucose from acid-hydrolyzed inulin. The polyfructosans, in contrast to the difructose anhydrides, are readily hydrolyzed in acid solution.