Many leguminous plant seeds contain galactomannans. Guar gum is obtained from the seeds of Cyamopsis tetragonolobus, an annual leguminous plant originating in India and Pakistan. Guar gum is known for its thickening properties. It is also cultivated in the United States.

Guar gum comes from the guar fruit pod; its seeds have an average diameter of about 5 mm. They contain a reserve substance, the albumen. From the outside to the interior, the fruit consists of:

• The hull.
• The albumen or endosperm, which is light cream in color, is made up of two hemispherical segments (splits) which surround the germ. Its major constituent is the polysaccharide.
• The germ which is rich in protein.

Interest in guar gum is fairly recent: its initial development was due to a lack of locust bean gum in the 1940s. Its large-scale industrial production dates from the 1950s.

Guar Gum Properties

• Instant viscosity development at room temperature (cold soluble)
• Creates a long (slimy) texture with a reduced flavor release
• No interaction (gelation) with other polysaccharides but high synergistic effect with xanthan (viscosity)