Cereal Chem 54:813 - 819.  |  VIEW ARTICLE
Water-Soluble Nonstarchy Polysaccharides of Composite Flours. II. The Effect of Polysaccharides from Yam (Dioscorea) and Cassava Flours on the Rheological Behavior of Wheat Dough.

S. Sefa-Dedeh, B. MacDonald, and V. F. Rasper. Copyright 1977 by the American Association of Cereal Chemists, Inc. 

Water-soluble nonstarchy polysaccharides (W.S.N.P.) extracted from flours milled from dried tubers of the two most common West African species of yam (Dioscorea rotundata Poir. and D. alata L.) and roots of cassava (Manihot utilissima Pohl., cv. Ankra) were tested for their effect on the rheological behavior of wheat dough during mixing and in simple tension. W.S.N.P. were prepared in the same way as water- soluble wheat "pentosans" of a typical bread flour which were used as a standard for comparison. While 1% replacement of wheat flour with an equal amount of cassava W.S.N.P. resulted in a reduced farinograph absorption of the mixture, yam W.S.N.P. as well as wheat pentosans exhibited an oposite effect. The highest increase in farinograph absorption (4.7%) followed the substitution of wheat flour with W.S.N.P. of D. rotundata Poir. origin. Analysis of data obtained in simple tension revealed that the tested materials (with the exception of D. rotundata Poir. W.S.N.P.) behaved as a rheologically inert material showing no significant effect on parameters other than those influenced by the changes in the water absorption characteristics. A distinct "strengthening" effect was noticed with doughs containing D. rotundata Poir. W.S.N.P., which was unrelated to the high water-binding capacity of this material. In rheological tests on bromated doughs, all W.S.N.P. appeared as an inert material with respect to the bromate reaction.