Sticky situation: Swetha Sivakumar on how gavar got into the oil business

It is difficult to imagine that gavar (Cyamopsis tetragonoloba), the vegetable relished across the subcontinent for thousands of years, plays a key role in fracking operations around the world. We’ll get to exactly what fracking is in a bit, but it all ties in because of the gum that gavar or guar contains.

PREMIUM

These beans are rich in fibre and potassium and can help lower levels of bad cholesterol in the body. It’s part of the reason we eat them, and use them in fodder.

Gavar is a hardy plant that grows well in dry and arid lands; Rajasthan is a leading producer. Its gumminess comes partly from the plant’s ability to grab any water it has access to and hold on to it. It does this using highly branched molecules made up of sugars such as galactose and mannose.

Gum was first extracted from gavar in 1945, amid a shortage of locust-bean gum. (Locust bean comes from the carob tree, which grows in Mediterranean countries such as Spain, Italy and Portugal, and supplies were greatly impacted during World War 2.)

So, amid the war, American processed-foods giant General Mills began trying to find an alternative, and hit upon gavar. Its bean is 15% husk, 45% germ (the plant embryo), and 45% endosperm (the food for the growing embryo). The gum comes from grinding up the endosperm. The byproduct of this process, guar meal, is used to enrich fodder.

Guar gum is a hydrocolloid, which means that it forms a gel when dispersed in water. It dissolves in hot and cold water, which makes it very useful to the food industry. It is added to ice-cream to inhibit ice-crystal growth; helps thicken packaged soups and sauces; improves flow rates in bottled salad dressings.

It even made its way, rather dangerously, into the diet-pill industry. In 1992, the US Food and Drug Administration (FDA) banned the use of guar gum in “diet pills” because it was found to cause oesophageal and small-bowel obstructions. People popping these pills (never a good idea) were not aware that the gum can expand by 10 to 20 times when it meets a liquid.

This ability to hold fast and expand has proved extremely useful in a range of industries. As with locust-bean gum, guar can arrest the flow of colours in cloth and paper, and is widely used in the printing and textile industries. It is used in aerially dispersed fire-retardants, to transform liquids into viscous blankets to help contain wildfires. It is used in the cosmetics industry.

But all these applications faded into the background when it was discovered, in 2010, that guar gum could help in the fracking process. The technical term is hydraulic fracturing; fracking is a popularised contraction. The process involves injecting water, sand and chemicals into a well at high pressure, to break up bedrock in order to access oil or gas pockets below. Potential consequences of fracking — and this is why it is so heavily protested — range from minor earthquakes to unusable groundwater. Toxic gasses are also often released into the air.

Guar gum is pumped into bedrock during the fracking process, to keep the gash propped open. It takes a lot of the gum to do this.

A single hydrofracking well (about 5 acres across; 10,000 ft deep), requires 10 tonnes. With about 1 million fracking wells operational in the US alone, demand skyrocketed. In 2012, prices shot up to such a degree that the American oilfield-service giant Halliburton informed shareholders that guar gum prices now accounted for a third of fracking costs.

Companies across industries began looking for alternatives, and xanthan gum began to replace guar. The former is made by fermenting sugars that are fed to a bacteria called Xanthomonas campestris, in huge industrial tanks. The two are now evenly priced and used almost interchangeably. Many companies combine them for a more stable stabiliser.

I do think the best thing one can do with gavar, though, is cook it with a few spices, add a little ghee, and eat it hot with fresh chapatis.

(To reach Swetha Sivakumar with questions or feedback, email [email protected])