Baobab Monograph.pdf - Crops for the Future

4.4 Other constituents
4.4.1 Mucilage
Numerous foodstuffs, particularly in West Africa, are mucilaginous: this
provides a desired slimy consistency to local soups and stews. Woolfe et al.,
(1977) in Ghana conducted a detailed study of the mucilage produced from
baobab leaves.
The most interesting feature is the high protein and mineral content both in
crude and purified mucilage. The mucilage contains a very small amount of
neutral sugars: rhamnose and galactose. Uronic acid is present as a mixture
of galacturonic and glucuronic acids. The relatively high proportion of
uronic acids classifies the mucilage as a galacturonorhamnan polysaccharide
which is acidic.
Viscosity depends on the mix of carbohydrates, proteins and minerals in the
mucilage and is lowered with cooking at high temperatures. Nonetheless,
baobab mucilage has great potential as a thickening agent.
4.4.2 Pectin
Fruit pulp is rich in pectin, most of it being water soluble with a low content
of protopectin. It was found to have a low degree of esterificaton. Intrinsic
viscosity values of the water soluble pectin are about one fifth of those of
commercial apple pectin and hence does not give a good jelly of high solids
content because it tends to precipitate rapidly in acid media to form irregular
gels (Nour et al., 1980).
4.4.3 Anti-nutritional factors
Upon cooking or frying, polyunsaturated fatty acids of seed oil undergo
transformations such as oxidation, polymerisation and cyclisation. Some of
the cyclic components may be toxic. The species of Adansonia contain
cyclopropene and cyclopropane fatty acids. Whereas cyclopropane fatty
acids appear to have no adverse effect on normal fatty acid metabolism,
cyclopropene fatty acids or sterculic acid can have adverse effects. This
summary is abstracted from Sebedio and Grandgirard (1989) who provided
the data in table 4.11 based on earlier analysis by others.
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