|MadSci Network: Biochemistry|
First of all, flatulence is the unwanted production of gases such as methane, carbon dioxide, nitrogen, hydrogen, oxygen, etc.. These gases are actually formed by bacteria in your intestines as they metabolize certain complex sugars which your body cannot digest. For instance, beans commonly contain complex oligosaccharides such as raffinose and stachyose. The bacteria ferment these carbohydrates in your colon and give off the aforementioned gases as byproducts. When you eat foods such as raisin bran you get the same effect because bran, which is simply indigestible carbohydrate, is fermented in your gut by these microbes. Incidentally, the foul smell of flatulence is due to the presence of volatile metabolic products from residual proteins and fats.
Beano helps to prevent flatulence because it contains the enzyme beta-galactosidase. This enzyme is capable of breaking down the complex sugars into more suitable forms that your body can digest. Therefore, the bacteria never get a chance to ferment the suspect carbohydrates because they are already degraded.
This whole scenario is very similar to that experienced by lactose intolerant people. These folks lack the enzyme lactase, which breaks down lactose (a disaccharide) into glucose and galactose (both monosaccharides). So, once again, the indigestible sugar passes into the colon and bacteria ferment it. This is why lactose intolerant individuals commonly experience flatulence after eating foods containing lactose. Of course, just as with Beano, a lactase containing supplement can be taken to avoid the problem.
Hope this helps.
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