2009_Book_FoodChemistry

4.4 Polysaccharides 309
aroma concentrates. For example, essential oils
are emulsified with gum arabic solution and then
spray-dried. In this process, the polysaccharide
forms a film surrounding the oil droplet, which
then protects the oil against oxidation and other
changes.
4.4.4.6 Gum Ghatti
4.4.4.6.1 Occurrence
Gum ghatti is an exudate from the tree Anogeissus
latifolia found in India and Ceylon.
4.4.4.6.2 Structure, Properties
Fig. 4.21. Viscosity curve of an aqueous gum arabic
solution (according to Whistler, 1973) (25.5 ◦ C, Brookfield
viscometer)
4.4.4.5.3 Utilization
Gum arabic is used as an emulsifier and stabilizer,
e. g., in baked products. It retards sugar crystallization
and fat separation in confectionery products
and large ice crystal formation in ice creams,
and can be used as a foam stabilizer in bever
ages. Gum arabic is also applied as a flavor fixative
in the production of encapsulated, powdered
The building blocks are L-arabinose, D-galactose,
D-mannose, D-xylose, and D-glucuronic acid.
L-Rhamnose has also been detected. The sugars
are partially acetylated (5.5% acetyl groups based
on dry weight). Three characteristic structural
elements have been detected (cf. Formula 4.141).
This acidic polysaccharide occurs as a Ca/Mg
salt. Gum ghatti is soluble in water to the extent
of ca. 90% and dispersible. Although it produces
solutions that are more viscous than gum arabic,
it is less soluble.
4.4.4.6.3 Utilization
Like gum arabic, gum ghatti can be used for the
stabilization of suspensions and emulsions.
(4.141)