Water-soluble dietary fiber and its application in food

Overview of water-soluble dietary fiber

Dietary fiber (DF) is usually considered to be a type of fiber that cannot be digested by human digestive enzymes. It is mainly composed of edible plant cell wall residues (cellulose, hemicellulose, lignin, etc.) and related substances associated with it. composed of compounds. According to its solubility, it can be divided into two types: water-soluble dietary fiber and insoluble dietary fiber.

Common water-soluble dietary fibers mainly include: inulin, glucan, resistant starch, chitosan, oat beta-glucan, guar gum, sodium alginate, fungal polysaccharide, etc. Common foods include barley and soybeans. Foods such as greens, carrots, citrus, flax, oats and oat bran are rich in water-soluble fiber.

In comparison, water-soluble dietary fiber has good processing properties and better physiological functions. In recent years, it has been used as a thickening agent, expanding agent, formulation aid and filler in food processing, and is widely used in low-energy foods. The production and development of food and functional foods, and water-based dietary fiber-related foods have huge room for development and broad market prospects.

Physicochemical properties and functions of water-soluble dietary fiber

1. High water retention, high expansion and function

There are many hydrophilic genes in the structure of water-soluble dietary fiber, which has strong water absorption, high water retention and high swelling property. It can increase stool volume and defecation speed, reduce pressure in the rectum and urinary system, relieve symptoms of urinary system diseases such as cystitis, bladder stones, and kidney stones, and can quickly excrete toxins from the body to prevent constipation and rectal cancer.

The high water retention and high expansion properties of dietary fiber delay gastric emptying, making people feel full in the stomach and reducing food intake, which is beneficial to preventing obesity and losing weight.

2. Adsorption and boiling effect and function

There are many active genes on the surface of water-soluble dietary fiber, which can combine and adsorb organic molecules such as cholesterol and bile acids, inhibit the increase in total cholesterol concentration, reduce the synthesis and absorption of human cholesterol and salts, and reduce cholesterol in human serum and liver, thus It can prevent coronary arteriosclerosis and prevent cardiovascular diseases.

3. Fermentation and adjustment of intestinal microbiota function

Soluble dietary fiber can be fermented by beneficial bacteria in the large intestine into organic acids such as acetic acid and lactic acid, which can reduce intestinal pH, promote the growth of beneficial intestinal bacteria Bifidobacterium, prevent intestinal mucosal atrophy, and maintain intestinal microbial balance and health. The organic acids produced by fermentation can speed up the peristalsis and digestion of food in the gastrointestinal tract, promote fecal excretion, prevent toxic substances in the intestine from irritating the intestinal wall and prevent toxins from staying too long, and prevent colon cancer.

4. No energy replenishment and obesity prevention functions

Soluble dietary fiber binds water (absorbs water) and expands in volume. It plays a filling role in the intestines and easily causes a feeling of satiety. At the same time, dietary fiber also affects the absorption of available carbohydrates and other components in the intestines. Absorption and digestion also make people less likely to feel hungry. Therefore, dietary fiber is very beneficial to preventing obesity.

5. Solubility, viscosity and their functions

Soluble dietary fiber is sticky and has a great impact on food viscosity. Due to the increased viscosity, the contact between the intestinal contents and the intestinal mucosa is reduced, thereby delaying the absorption rate, stabilizing blood sugar levels after eating for diabetic patients, promoting the secretion of insulin from the pancreas, and conducive to the supply and metabolism of sugar. Increasing dietary fiber in food can improve the sensitivity of peripheral tissues to insulin and regulate and control blood sugar levels in diabetics.

Application of water-soluble dietary fiber in food

Water-soluble dietary fiber, as a new type of dietary fiber and thickener, swelling agent, formula aid, filler, etc., is mainly used in low-energy, high-fiber and other functional foods. In low-energy foods, water-soluble dietary fiber can partially or completely replace sugar and fat. While reducing food energy, it can maintain the original flavor and texture of the food and bring a satisfying taste. In addition to health products, water-soluble dietary fiber is widely used in beverages, dairy products, candy, baking and other food fields due to its good solubility, stability, mild taste and other properties.