Amylose

See also: amylase

THE "STARCHY, NON-STICKY" STARCH

Amylose is a polysaccharide found in starch, the main storage carbohydrate in plants. It plays a crucial role in various biological processes and contributes to the unique properties of starchy foods.

Structure and Properties:

• Made up of long, unbranched chains of glucose molecules linked by α-1,4 glycosidic bonds.
• This linear structure gives it a more rigid and crystalline form compared to amylopectin, another component of starch.
• Accounts for about 20-30% of total starch content in various plants, including rice, potatoes, and wheat.
• Known for its "starchy, non-sticky" properties, contributing to the firmness and texture of certain starchy foods.
• Less soluble in water than amylopectin, making it a good source of resistant starch, which is not readily digested.

Biological Effects:

• Digestion:
  • Resistant starch in amylose is not broken down by digestive enzymes in the small intestine, reaching the large intestine where it ferments by gut bacteria.
  • This fermentation produces short-chain fatty acids (SCFAs), which offer various benefits:
    • Promote gut health by feeding beneficial bacteria.
    • May contribute to improved insulin sensitivity and blood sugar control.
    • May have anti-inflammatory effects.
• Glycemic index:
  • Amylose-rich starchy foods generally have a lower glycemic index (GI) compared to those high in amylopectin.
  • This means they cause a slower rise in blood sugar levels, potentially benefiting individuals with diabetes or those managing blood sugar.
• Satiety:
  • Resistant starch in amylose may contribute to a feeling of fullness and reduced appetite, potentially aiding weight management efforts.
• Other potential benefits:
  • Some research suggests amylose may have beneficial effects on cholesterol levels and colon health, but further studies are needed.

Applications:

• Food industry:
  • High-amylose starches are used in various food applications due to their unique properties:
    • Thickeners and stabilizers in sauces and soups.
    • Gelling agents in puddings and jellies.
    • Modifying texture and preventing stickiness in baked goods.
• Biodegradable materials:
  • Research explores using amylose to develop biodegradable plastics and films as eco-friendly alternatives.

Important Considerations:

• While offering potential health benefits, amylose should be consumed as part of a balanced diet and not as a sole source of dietary fiber.

Starch from Pueraria lobata and the amylose fraction alleviates dextran sodium sulfate induced colitis in mice.

Resistant starch** from high-amylose maize increases insulin sensitivity in overweight and obese men.

High-Amylose Wheat Lowers the Postprandial Glycemic Response to Bread in Healthy Adults: A Randomized Controlled Crossover Trial