Galactomannan solutions are rather stable and show practically no change in viscosity upon standing at room temperature (provided no microbial degradation occurs), slight pH changes or addition of salts. Prolonged heating at high temperature (boiling) reduces the viscosity. Similar to other hydrocolloids, galactomannans can be hydrolysed by microorganisms, consequently solutions should be sterilised or preserved for storage.
Interaction with other polysaccharides: One of the most interesting and useful properties of CBG (LBG) is its interaction with specific hydrocolloids resulting in a substantial viscosity increase or gel formation. The interaction is particularly strong with carrageenan and xanthan gum, producing soft or highly elastic gels, depending on the concentration of the gums. This synergistic effect of CBG (LBG) has found many important applications.
From a nutritional stand point, CBG (LBG) is regarded as a soluble dietary fibre. As such it is, contrary to starch, not digestible in the digestive tract (small intestine). CBG (LBG) is however partially fermented in the large intestine by microorganisms resulting in gas formation and production of short chain fatty acids (acetate, propionate) and, therefore, providing some energy to the organism. Since the exact digestibility is not yet known, the caloric value of nil is used for CBG (LBG) as well as dietary fibres in general, when calculating the energy value of foods. A discussion of this topic is in progress and a caloric value of 1 or 2 kcal/g can be expected in the future.