Guar is a Hindi word and its mean is “ Cow Food” . It is a drought tolerant legume which grows in hot . In the Asian sub-content It has historical uses .Guar is still used as cattle feed in India and Pakistan. The Gum pods and picked young used in cooking (Without removing the Try Sperm inhibitor by toasting it, Guar protein is not usable for human).
Guar has been cultivated in India and Pakistan for ages for use of its tender pods as fresh vegetables and other parts of the plant to be used as cattle feed. When in abundance the pods could also be used as cattle feed. Guar grows well in the semi-arid regions of North- Western India and adjoining areas of Pakistan.
Guar Gum is emulsifier , Thickener and stabilizer approved for use in wide range of foods. Cosmetics Pharmaceuticals . It is sold as a white to yellow odorless white powder which is available in different Viscosity’s and different Granulometry depending on the desired viscosity’s as a function of temperature , Time , and concentration . One advantages property of Guar Gum is that thickens without the application of heat.
Chemical Composition of Seed
Surprisingly, although guar primarily is grown for its gum content, very little is known about the variability of gum content in the seed of Cynamopsis Tetragonolobus. In his pioneering work, Anderson screened seeds of 163 speciesof legumes for sources of endosperm gums. He reported that guar seed contained about 50% endosperm and yielded approximately 42% gum. According to Goldstein and Alter the three major components of guar seed are the seed are the seed coat (14 – 17%)endosperm (35-42%) and germ (43-47%). The germ contains most of the protein in the seed while the endosperm contains the galactomanman gum. The chemical structure of guar gum consists of a linear chain of Diagnose units linked together by B-(1—4) glycoside linkages and having on certain D-mannose units a single D-galactose unit joined by an a (1—6) glycoside linkage. On the average, alternate D-mannose units bear a D-galactose unit. For additional information on the chemicals of guar gum.
Guar Gum is derived from the ground endosperm of the Guar plant , Cynamopsis ,Tetragonolobus belonging to the family leguminous . The Gaur plant is mainly grown in India and Pakistan the month of July to December . At harvest time the seed are extracted from the pod of the plant and then ground into Guar Gum.
The Guar gums , are extracted from guar seed . The plants are botanically known as Cynamopsis Tetragonolobus which belongs to the Leguminous family.
The Industrial processing of guar seed results in Two major products .
- The Gaur Gum
- The Gaur Meal (Guar Protein)
The Gaur meal is reach in protein content having 38% to 42% protein. The Guar meal is very important for poultry feed and cattle feed .It improve egg laying capacity of the poultry . Productivity of milk in enhanced when used in cattle feed The Guar meal is basically the husk and germ of the seed , Which is processed in multistage toaster by steam for detoxification .
Guar Gum is natural high molecular weight Polysaccharides composed of galactan and manna units. Polysaccharides are complex sugar molecules with nine or more simple sugars (monosaccharide) linked together. Examples of others types of Polysaccharides include starch and cellulose. Guar gum is a plant seed extract, containing about 80% of galactomanman, 10% moisture,
10% protein and trace amounts of heavy metals and ash. The amount of these impurities depends on the species, sources and purification process. Because the protein molecules are not chemically bounded to the galactomanman, guar gum can be easily purified by centrifugation.
The galactomanman of guar gum consists of a long linear mannan backbone and side chains of a single galactose unit. This feature allows guar gum to be soluble and gelling in water. Guar gum hydrates and swells rapidly in aqueous media to form viscous dispersions or gels. Consequently, chemicals or particles need “more energy” to “move around “inside this “more viscous” medium. Probably, because it forms a high viscous solution in aqueous medium, consumption of guar gum may retard chemicals like cholesterol and triglyceride travel to the intestine wall for absorption. Consequently, guar gum is observed to prevent cholesterol absorption and it lowers serum LDL cholesterol and triglyceride and increases glucose tolerance.
One of the important properties of guaran is its ability to hydrate rapidly in cold water to produced highly viscous solution. Hydration rates and water-binding properties of guar are dependent on the processing techniques used in making the gum and upon the finial condition of the solid material ,particularly Its particle size . Guar gum when completely hydrated forms a various colloidal thixotropic dispersion.
Solution of guar gum less then1% Are less Thixotropic them solutions of concentration of 1 % of higher. Viscosities of 0.3% solutions change only slightly with increasing shear rates, while at the same shear rate, solution of 1% concentration of higher change markedly as with most other gums , the viscosity of guar is dependent on time , Temperature , concentration , ph , Ionic strength , and the type of agitation . A 1% Aqueous dispersion of a good –quality guar gum has a viscosity of 3,000 to 6,000 cps.
In particle application, a hydration time about 2 hours is required to reach maximum viscosity . For some application in which there is a need for an immediate high initial viscosities , very fine mesh guar gum can be used.
|Gum Arabic 20% by wt)||50|
|Locust bean gum||100|
|High Viscosity Sodium Carboxyl methyl cellulose||300|