Post by Janny on Mar 16, 2005 14:02:44 GMT 10
Several chemical constituents of beans are responsible for an uncomfortable sometimes embarrassing consequence of eating legumes: the generation of gas in the digestive system.
The cause: Indigestible Carbohydrates
Everyone produces a mixture of gases from the intestines, just over a litre a day, thanks to the growth and metabolisms of our resident bacteria
Many legumes, epecially soy, navy and lima beans, cause a sudden increase in bacterial activity and gas production a few hours after they're consumed. This is because they contain large amounts of carbohydrates that human digestive enzymes can't convert into absorbable sugars.
These carbohydrates therefore leave the upper intestine unchanged and enter the lower reaches, where our resident bacterial population does the job we are unable to do.
One kind of troublesome carbohydrate is the aligosaccharides, which consist of three, four and five sugar molecules linked together in an unusual way. But the latest research suggests that the oligosaccharides are not the primary source of gas. The cell-wall cements generate just as much carbon dioxide and hydrogen as the oligosaccharides - and beans generally contain about twice as much of these carbohydrates as they do oligosaccharides.
The cures: Soaking, Long Soaking
A commonly used method for reducing the gassiness of beans is to boil them briefly in ample water, let them stand for an hour, then discard the soaking water and start the cookign with fresh water. This leaches out most of the water-soluble oligosaccharides but it also leaches out significant quantities of water-soluble vitamins, minerals, simple sugars and seed coat pigments: that is, mutrients, flavour, colour and antioxidants. That's a high price to pay.
An alternative is simple, prolonged cooking, which eventually breaks down much of the oligosaccharides and cell-wall cements into digestible single sugars. Oligosaccharides are also consumed by the bean during germination, and consumed by microbes during fermentation. So sprouts, miso and soy sauce as well as extracts such as bean curd, are less offensive than whole beans.
From Epicure - McGee on Food & Cooking
The cause: Indigestible Carbohydrates
Everyone produces a mixture of gases from the intestines, just over a litre a day, thanks to the growth and metabolisms of our resident bacteria
Many legumes, epecially soy, navy and lima beans, cause a sudden increase in bacterial activity and gas production a few hours after they're consumed. This is because they contain large amounts of carbohydrates that human digestive enzymes can't convert into absorbable sugars.
These carbohydrates therefore leave the upper intestine unchanged and enter the lower reaches, where our resident bacterial population does the job we are unable to do.
One kind of troublesome carbohydrate is the aligosaccharides, which consist of three, four and five sugar molecules linked together in an unusual way. But the latest research suggests that the oligosaccharides are not the primary source of gas. The cell-wall cements generate just as much carbon dioxide and hydrogen as the oligosaccharides - and beans generally contain about twice as much of these carbohydrates as they do oligosaccharides.
The cures: Soaking, Long Soaking
A commonly used method for reducing the gassiness of beans is to boil them briefly in ample water, let them stand for an hour, then discard the soaking water and start the cookign with fresh water. This leaches out most of the water-soluble oligosaccharides but it also leaches out significant quantities of water-soluble vitamins, minerals, simple sugars and seed coat pigments: that is, mutrients, flavour, colour and antioxidants. That's a high price to pay.
An alternative is simple, prolonged cooking, which eventually breaks down much of the oligosaccharides and cell-wall cements into digestible single sugars. Oligosaccharides are also consumed by the bean during germination, and consumed by microbes during fermentation. So sprouts, miso and soy sauce as well as extracts such as bean curd, are less offensive than whole beans.
From Epicure - McGee on Food & Cooking