Cluster bean (Cyamopsis tetragonoloba) is belong to Leguminosae family. The common name of cluster bean is “Guar” in Pakistan. Cluster bean crop has ability to with stand drought stress and can easily grow in arid to semiarid areas.
Guar can fix environmental nitrogen in soil through its roots in presence of bacteria and this process is called biological nitrogen fixation. People of Pakistan, United States and India are major trader of cluster bean seeds.
Guar needs minimum water to grow and gives higher yield. In the scenario of drought stress and climate change guar production is a best option for farmers of Pakistan because 350 to 450 mm water is enough to get high profit.
The temperature of the world increases day by day due to global warming and cluster bean can tolerate higher temperature. Cluster bean is leguminous crop and used as a green manure and livestock feed. The third main product is derived from it is gum powder easily available in market.
- Benefits of cluster bean gum
Guar gum constitutes carbohydrate polymer with different ratios of mannose and galactose sugars. It is raw product for paper industry. In food industry it is major ingredient of ketchup, drinks, and mayonnaise. The guar crop has no waste trash throughout its cycle from seeding to industrial use.
In frozen goods it is used for stabilization. It is also used in stabilization of ice cream. The biggest advantage of guar gum is hydrated rapidly in high temperature short time procedure. It requires HTST procedure because hydrocolloids can completely hydrate in a short manufacturing time.
Cluster bean gum has high H2O holding ability in both cold and warm water. It is easily used as a lubricant agent in the processing of stuffed meat goods and sausage food stuffs. In different bakery products guar gum is used in making dough particularly in flours having low gluten contents due to its good film characteristics.
The use of guar gum in bakery products is also greater the shelf life of products like rolls and breads due to soft texture & higher wetness retention. For dispersal of pulp in juices and syrups guar gum is commonly used in beverage industries.
In pharmaceuticals and cosmetics products gum is important ingredient for smooth look. It is used as thickening raw product in toothpastes and shampoos. It is used as smasher and binder in tablets. It is consumed for treatments of diseases like constipation, high cholesterol, diarrhea, weight loss, liver illness in pregnancy and high blood pressure.
In agriculture sector guar gum is used as adhesive agent for coating fertilizers and seeds. It mixed with borax and (poly) vinyl alcohol for enhancing water holding capability of the soil. The important thing about guar gum is that, it is biodegradable. So it is environment friendly product.
- Processing of guar gum
The seeds of cluster bean are crashed. The germs of seeds are separated from endosperms during crashing process. The endosperms are divided into two parts and called as cluster bean splits. When husked is removed from the endosperm by using polishing method then refined form of splits are obtained.
The guar gum processing techniques depends on its desired product. The quality of product is tested by hydration capacity, its particle size and microorganism’s contamination. In a double cone food mixer guar split is separated and soaked for hydration. This step is very important and determined the final hydration rate of product.
After soaking process splits are milled in a flaker to obtained required splits size followed by drying process. When this procedure is done then passed through desired size rotary screens and guar powder is obtained. The waste material is recycled for further processing.
During this process byproducts like germ and husk are used for livestock feed due to high protein contents. Different grades are sold in the market depended on different rate of hydration, color, particle size and viscosity.
In leguminous crops toxic contents are also present. The guar meal contained approximately 17.5 percent toxicity level due to presence of anti-nutrients growth inhibitor like trypsin and not digested in animal intestinal tract. So it is most important consideration while guar meal is used for feed purpose.
Cluster bean is considered as a minor crop in Pakistan. The byproducts of guar also give higher profits. It is enhanced soil productivity and fertility due to environmental nitrogen fixation. Now it’s a time to work on minor crops which required less inputs and increased the farmer’s profits. The trainings about guar production and its byproducts processing should be arranged for farmers by government and private organizations to increase the farmer’s profit and for their better life style in Pakistan.
Authors:Iqra Ghafoor and Muqarrab Ali at Department of Agronomy, Muhammad Nawaz Shareef University of Agriculture Multan.