Guar Gum is derived from the seeds of the Guar plant “Cyamopsis
tetragonalobus”. It is an annual plant, about 4 feet high, vertically stalked,
with large leaves and clusters of bean-like pods. Each pod is about 5-8
CMS long and has on an average 6-9 small, grayish-white pea shaped seeds. Guar
is a hardy, drought resistant bush, which grows well in the semi arid areas of
west and north-west India and parts of Pakistan. Guar grows best in sandy
soils, If needs moderate, intermittent rainfall with lots of sunshine.
Too much precipitation can cause the plant to become more “ leafy” thereby
reducing the number of pods and/or the number of seeds per pod, which affects
the size, and yield of seeds. The crop is sown after the first rains in July
and harvested in late October. The Pods are then sun dried, manually
separated from the seeds and the seeds are supplied to the industry for
processing. Tender green Guar pods are also consumed as a vegetable and
cattle-feed in India.
The Guar seeds are dicotyledonous having a diameter of about 2.0-3.0 mm. The seeds make-up about 60 % -70 % of the pod weight. The germ is completely enveloped by the 2 halves of the endosperm, and if is the endosperm that is the source of the gum. The tough seed skin or husk is of a fibrous nature, composed of compressed thin layers of cellulosic material.
The gum is commercially extracted from the seeds essentially by a mechanical process of roasting, differential attrition, sieving and polishing.The seeds are broken and the germ is separated from the endosperm . 2 halves of the endosperm are obtained from each seed and are known as Undehusked Guar Splits. When the fine layer of fibrous material, which forms the husk, is removed and separated from the endosperm hales by polishing, Refined Guar Splits are obtained. The husk and germ are rich in protein and form a valuable cattle-feed. The larger germ particles have a high content of oil and albuminoids (o&a) – about 55% The smaller germ particles have an o & a content of about 40% and the husk about 25% o & a. Various standardized blends of these “Guar meals” can be made to achieve standard o &a contents. Guar meal may also be toasted to reduce odour and remove trypsin inhibitors. This is known as toasted Guar meal and is sold in the international markets. This product is usually standardized of 45% o&a content.
The refined Guar splits are then treated and finished into powders by a variety of routes and processing techniques depending upon the end product desired. High purity Guar gums like Guar gum for foods. Feeds and pharmaceutical applications can be produced in many different viscosities hydration to suit specific applications. Various modified/derivatised Guar gums such as hydrolyzed, hydroxyalkyl, carboxyalkyl, oxidised, sulphated, borated, cationic and various combination of these are commercially useful for a number of industry applications.
Chemistry & Structure
Guar gum Guar Gum is a plant seeds hydrocolloid a cold and hot water soluble galactomannan polysaccharide. Chemically, Guar gum is composed of beta 1,4 linked linear mannose backbone chain with single galactose side unit on approximately every other mannose unit, in a 1,6 alpha linkage.
The molecular structure reveals that it is a rigid rod-like polymer due to the beta linkage between the monomer units. The mannose to galactose ratio has been estimated at 1,8:1 to 2:1.
Recent studies indicate that the galactose side units may not follow a regular spacing pattern, but in fact, may appear in “cluster” and on either side of the mannose backbone.
The Guar seeds are dicotyledonous having a diameter of about 2.0-3.0 mm. The seeds make-up about 60 % -70 % of the pod weight. The germ is completely enveloped by the 2 halves of the endosperm, and if is the endosperm that is the source of the gum. The tough seed skin or husk is of a fibrous nature, composed of compressed thin layers of cellulosic material.
The gum is commercially extracted from the seeds essentially by a mechanical process of roasting, differential attrition, sieving and polishing.The seeds are broken and the germ is separated from the endosperm . 2 halves of the endosperm are obtained from each seed and are known as Undehusked Guar Splits. When the fine layer of fibrous material, which forms the husk, is removed and separated from the endosperm hales by polishing, Refined Guar Splits are obtained. The husk and germ are rich in protein and form a valuable cattle-feed. The larger germ particles have a high content of oil and albuminoids (o&a) – about 55% The smaller germ particles have an o & a content of about 40% and the husk about 25% o & a. Various standardized blends of these “Guar meals” can be made to achieve standard o &a contents. Guar meal may also be toasted to reduce odour and remove trypsin inhibitors. This is known as toasted Guar meal and is sold in the international markets. This product is usually standardized of 45% o&a content.
The refined Guar splits are then treated and finished into powders by a variety of routes and processing techniques depending upon the end product desired. High purity Guar gums like Guar gum for foods. Feeds and pharmaceutical applications can be produced in many different viscosities hydration to suit specific applications. Various modified/derivatised Guar gums such as hydrolyzed, hydroxyalkyl, carboxyalkyl, oxidised, sulphated, borated, cationic and various combination of these are commercially useful for a number of industry applications.
Chemistry & Structure
Guar gum Guar Gum is a plant seeds hydrocolloid a cold and hot water soluble galactomannan polysaccharide. Chemically, Guar gum is composed of beta 1,4 linked linear mannose backbone chain with single galactose side unit on approximately every other mannose unit, in a 1,6 alpha linkage.
The molecular structure reveals that it is a rigid rod-like polymer due to the beta linkage between the monomer units. The mannose to galactose ratio has been estimated at 1,8:1 to 2:1.
Recent studies indicate that the galactose side units may not follow a regular spacing pattern, but in fact, may appear in “cluster” and on either side of the mannose backbone.
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