Food Chemistry

4.4 Polysaccharides 309

Fig. 4.21.Viscosity curve of an aqueous gum arabic
solution (according toWhistler, 1973) (25. 5 ◦C, Brook-
field viscometer)

4.4.4.5.3 Utilization

Gum arabic is used as an emulsifier and stabilizer,
e. g., in baked products. It retards sugar crystal-
lization and fat separation in confectionery prod-
ucts 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 fix-
ative in the production of encapsulated, powdered

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 GumGhatti

4.4.4.6.1 Occurrence.............................................

Gum ghatti is an exudate from the treeAnogeissus

latifoliafound in India and Ceylon.

4.4.4.6.2 Structure,Properties.....................................

The building blocks areL-arabinose,D-galactose,

D-mannose, D-xylose, andD-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)