CARBOHYDRATES AND DIETARY FIBERS IN SOYBEAN

Soybean and its processed products are good food choices for diabetics due to the relatively lower available carbohydrate but higher dietary fibre content. There are several types of carbohydrates, namely sugar (mono- and di-saccharides), oligosaccharides and polysaccharides including starch and non-starch polysaccharides (NSP). The main types of carbohydrates in soybean seeds are sucrose (disaccharide) and stachyose, raffinose, and verbacosa (oligosaccharides).

The most abundant type of carbohydrate found in soybean seeds is oligosaccharides (mainly stachyose) which cannot be digested by enzymes in the small intestine so that they will reach the large intestine. In the large intestine, oligosaccharides stimulate the growth of intestinal bacteria such as bifidobacteria which then ferment oligosaccharides into short chain fatty acids such as butyric acid, propionate acid, acetic acid and gases such as carbon dioxide gas, methane gas and hydrogen gas.

Carbohydrates that cannot be digested by the body but can be fermented by bacteria in the intestine are referred to as dietary fiber. Dietary fiber helps the digestion process and is beneficial for health. There are two types of dietary fiber, namely soluble dietary fiber and insoluble dietary fiber. Soluble dietary fiber has been found to help reduce blood cholesterol while insoluble dietary fiber facilitates the bowel movement.