Digesting Beans - What Causes Gas?

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While beans are inexpensive, easy to prepare, tasty, and loaded with protein and carbohydrates, many humans avoid them because of the problem of intestinal gas. Gas is caused by the body's inability to digest the complex carbohydrates found in beans.

Carbohydrates can be made of a single sugar such as glucose or fructose; a double sugar, like lactose, found in dairy products; or many sugars. Before any carbohydrate can be absorbed from the intestines into the bloodstream, it must be broken down into a single sugar. If it can't be broken down, it can't be absorbed, and will pass whole into the lower intestinal tract where bacteria ferment it, causing gas. Soaking beans before cooking them will help remove some of these gas-causing sugars and make digesting them easier.

Beans contain a triple sugar, stachyose, a quadruple sugar, raffinose, and a five sugar, verbascose, and since most humans can't digest these sugars, the bacteria go to work on them and create fumes through a fermentation process. Researchers have found that the enzyme alpha-galactosidase will help break down these complex sugars. A product, marketed under the name Beano, to reduce intestinal gas formation uses this enzyme to help reduce the formation of intestinal gas. It contains alpha-galactosidase derived from the mold, Aspergillus niger.

Beans and Digestion

Problems with digestion is caused by the complex sugars (oligosaccharides) in beans, and soaking is recommended to allow a greater amount of that sugar to dissolve, thus helping the beans to be more easily digested. The harder the class of beans, the more troublesome they are to digest.

Left unsoaked, the beans still have all the oligosaccharides, which means basically, you’re dumping all that sugar on the natural bacteria in your colon, which just love it. They thrive on sugar so they begin to grow... and grow, and one of the by-products of all that growth is…you guessed it, lots and lots of GAS!

So now you know that, flatulence is a result of two things, mostly the oligosaccharides in the beans which our enzymes can't break them down, but also the type of bacteria housed in your gut. The bacteria population can adapt to the beans is you eat them regularly, and you can also try various remedies like Beano.

To Improve Digestion

There is no way to completely avoid gas when eating beans. Some people are more susceptible than others, but here are some things that may help minimize the digesting problems:

Eat beans regularly to build up your body's ability to process them. Increase the quantities you eat slowly, however.
Drink more fluids than normal when you are eating beans.
Soak the beans thoroughly. The soaking process dissolves gas-causing elements into the soaking water.
After boiling the beans, if the recipe allows, discard that water and rinse the beans again.
Soak the beans and discard the soaking water prior to cooking.
Rinse thoroughly under cold running water
Cook the beans thoroughly.
Eat small quantities of beans for several days until your body adjusts to them.
Try legumes that are easier to digest from the soft beans group
Avoid the hard beans that are difficult to digest.

Says:
You might want to try a product called Beano™. As stated on the label, Beano is a "food enzyme supplement that helps stop gas before it starts" by breaking down the gas-producing sugars in beans as well as in broccoli, grains, and other gas-producing foods. Directions state to add five drops of Beano to your first bite of food. Heat inactivates the enzyme, so it cannot be added during cooking.