Fructan

2000, Nordic Council of Ministers, Safety evaluation of fructans, TemaNord, page 17, Fructans are also produced by algae, fungi and bacteria (Nelson & Smith, 1986) There is a substantial variation in both linkage types and number of carbohydrate monomers making up the fructans. The functionality, if any, of the different fructan structures is as yet not clear.

2010, Peter J. O'Brien, Cynthia Y. Feng, Owen Lee, Q. Dong, Rhea Mehta, Jeff Bruce, W. Robert Bruce, 7: Fructose-Derived Endogenous Toxins, Peter J. O'Brien, William Robert Bruce (editors), Endogenous Toxins: Targets for Disease Treatment and Prevention, Volume 1, Wiley (Wiley-VCH), page 176, Fructose can also exist in the diet as fructans and dietary sugar alcohols. Fructans (fructo-oligosaccharides) are polymers of fructose molecules that are not absorbed by the intestine but are metabolized by anaerobic colonic bacteria.

All the listed cultivars contain fructans in different amounts as reserve carbohydrate. Another source of fructans are caryopses of grasses and flours of wheat, rye, oat, and barley, which contain between 1 and 7% fructans, depending on the degree of fine milling and applied technological processing.