Guar Split

GUAM SPLIT.

Guar gum, also called guaran, is a galactomannan. It is primarily the ground endosperm of guar beans. The guar seeds are dehusked, milled and screened to obtain the guar gum. It is typically produced as a free-flowing, off-white powder.

DATE.
2014, 17,
June
guarsplit

Production and trade

The guar bean is principally grown in India, Pakistan, US, China, Australia and Africa. India produces 2.5 – 3.5 million tonnes of guar annually, making it the largest producer with about 80% of world production.
In India, Rajasthan, Gujarat and Haryana are the main producing regions, and Jodhpur, Sri Ganganagar and Hanumangarh in Rajasthan are the major Guar trading markets. Hanumangarh – Ganganagar [2] is the main production area for best quality guar beans, so called “Fast-Hydrating Guar”.

The United States has produced 4,600 to 14,000 tonnes of guar over the last 5 years. As many as 50,000 acres of guar have been grown in West Texas over the last 50 years.

The world production for guar gum and its derivatives is about 1.0 Million tonnes. Industrial guar gum accounts for about 70% of the total demand. Mainly it is used as a proppanttransport / proppant suspending agent in Hydraulic Fracturing Process. In 2012 guar prices increased by 900-1000%. The main reason for this large scale price rise was the inventory build up by companies like Halliburton and Schlumberger, amidst the fear of shortage of guar gum for drilling due to ongoing drought in Rajasthan. 2013 was a strong year for guar sowing and production in India. The total sowing area rose by 21 percent in 2013 to reach 10.6 million acres. Rajasthan, Haryana, and Gujarat – the three key guar-producing states – exceeded the sowing area target set by their respective agriculture departments. Non-traditional guar cultivators in other Indian states also showed keen interest in the crop in 2013.

Properties

Chemical composition

Chemically, guar gum is a polysaccharide composed of the sugars galactose and mannose. The backbone is a linear chain of β 1,4-linked mannose residues to which galactose residues are 1,6-linked at every second mannose, forming short side-branches.

Solubility and viscosity

Guar gum is more soluble than locust bean gum and is a better stabilizer, as it has more galactose branch points. Unlike locust bean gum, it is not self-gelling. However, either borax or calcium can cross-link guar gum, causing it to gel. In water, it is nonionic and hydrocolloidal. It is not affected by ionic strength or pH, but will degrade at extremes pH and temperature (e.g. pH 3 at 50 °C). It remains stable in solution over pH range 5-7. Strong acids cause hydrolysis and loss of viscosity, and alkalies in strong concentration also tend to reduce viscosity. It is insoluble in most hydrocarbon solvents.

Guar gum shows high low-shear viscosity but is strongly shear-thinning. It is very thixotropic above 1% concentration, but below 0.3%, the thixotropy is slight. It has much greater low-shear viscosity than that of locust bean gum, and also generally greater than that of other hydrocolloids. Guar gum shows viscosity synergy with xanthan gum. Guar gum andmicellar casein mixtures can be slightly thixotropic if a biphase system forms.

Thickening

Guar gum is economical because it has almost eight times the water-thickening potency of cornstarch – only a very small quantity is needed for producing sufficient viscosity. Thus, it can be used in various multiphase formulations: as an emulsifier because it helps to prevent oil droplets from coalescing, and/or as a stabilizer because it helps to prevent solid particles from settling.

Ice crystal growth

Guar gum retards ice crystal growth nonspecifically by slowing mass transfer across the solid/liquid interface. It shows good stability during freeze-thaw cycles.

share on