The Magical Fruit: Why Beans Cause Flatulence

No Comments by Beatrice Preti on 5th Jan 2013

why, exactly, do beans cause wind? And is there any way to prevent it?

Red, yellow, black, and brown. Boiled, stewed, baked, and sautéed. They sit before you in a rainbow of variety, yet your body quivers at the thought of the taste… and the consequences.

Almost everyone knows of the correlation between beans and flatulence. This negative publicity often results in beans being pushed to the wayside, substituted by more society-friendly food choices.

A Tasty Bean Salad
Source: Wikimedia Commons

But why, exactly, do beans cause wind? And is there any way to prevent it?

Beans offer an inexpensive high-protein, low-fat option for the world’s hungry. Packed with fibre, B vitamins, iron – but no cholesterol – beans are a powerhouse of deliciousness for the taste bud’s delight. Beans also contain complex sugars called oligosaccharides; although these provide the energy we need to walk, talk, and read the words across a page, they also contribute greatly to the flatulence known to bean-lovers everywhere.

A particular oligosaccharide, raffinose, is rampant among the bean family. Raffinose is indigestible by normal human processes; only the natural bacterial flora in the intestines can utilise the carbohydrate. The by-product of bacterial metabolism? Flatulence.

The amount and type (smell) of the flatulence can vary from person to person. Intestinal bacteria differ in number and type; these natural variations can allow one person to enjoy beans with no apparent consequences, while the next suffers terribly from even a bite.

Beans should be soft and mushy when properly cooked, not hard or “crunchy”.

Is there hope for the bean sufferer? Yes, of course! The savvy consumer can take multiple steps to ensure maximum comfort – and minimum embarrassment – when enjoying this tricky food.

Oligosaccharides are water-soluble. This means soaking, draining, cooking, and draining again can remove a great deal of the offending raffinose. Pre-cooking tinned beans swimming in liquid trap raffinose inside the tin, forces them to absorb more of the carbohydrate than they would normally.

Avoid Embarrassment – Cook your beans!
Wikimedia Commons

Ensure beans are completely cooked as raw beans can suck water away from the gastrointestinal system, drying the tract and increasing flatulence. Beans should be soft and mushy when properly cooked, not hard or “crunchy”. Soaking beans overnight can help reduce cooking times.

Alpha-galactosidase is an enzyme capable of properly digesting raffinose. It is extracted from fungi and sold as the pharmaceutical Beano. Beano, which is taken prophylactically, is available as tablets and melting strips. Beano is considered by many to be a “safe” medication as it uses natural means to correct a human deficiency.

Finally, younger beans do contain lower levels of oligosaccharides than older beans. Although it can be difficult to tell the age of dried beans, younger beans usually have a lighter colour than their older counterparts. Older beans are also likely to be more cracked and damaged.