Galactomannans solution properties

Robinson, G., Ross-Murphy, S. B., and Morris, E. R. (1982). Viscosity-molecular weight relationships, intrinsic chain flexibility, and dynamic solution properties of guar galactomannan. Carbohydr. Res. 107 17-32. 

Ganter J., MUas M., Rinaudo M., Study of solution properties of galactomannan from the seeds of Mimosa scabreUa, Carbohydr. Polym., 17, 1992, 171-175. 

Two fundamental properties determine much of the behavior of polymers the molecular weight and the conformation (molecular shape). Because of the very high viscosities of even dilute solutions of galactomannans, determinations of the molecular weight are technically difficult. 

The linear, but highly branched, molecular structure of the galactomannans is the reason for some specific properties which are quite different from those of the unbranched cellulose-like and water-insoluble mannans and glucomannans. Galactomannans are hydrated in cold water and give stable solutions even in acidic formulas. The interactions of galactomannans with other polysaccharides are the base of a variety of industrial applications. 

DoubUer, J. L., and Launay, B. (1976). Rheological properties of galactomannan in aqueous solutions Effect of concentration and molecular weight. Proc. Int. Congr. Rheol, 6th, pp. 532-533. 

Although the water solubility of galactomannans is relatively low, the ensuing solutions display interesting rheological properties as thickeners. They have been modified by the specific oxidation at C-6 position with TEMPO in order to increase their solubility by transforming them into new polyelectrolytes [98, 99]. 

The molecular weight of the galactomannan is close to 310kdal. Physical properties correspond to those of guar gum, except the viscosity of the solution is not as high (cf. Table 4.21). 

McCleary B.V., Amado R., Waibel R., Neukon H. (1981). Effect of galactose content on the solution and interaction properties of guar and carob galactomannans. Carbohydrate Research, 92, 269-285. 

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