Search results
Results From The WOW.Com Content Network
Retrogradation is a reaction that takes place when the amylose and amylopectin chains in cooked, gelatinized starch realign themselves as the cooked starch cools. [1]When native starch is heated and dissolved in water, the crystalline structure of amylose and amylopectin molecules is lost and they hydrate to form a viscous solution.
If cooking includes excess water, the starch is gelatinized and becomes more digestible. However, if these starch gels are then cooled, they can form starch crystals resistant to digestive enzymes (type RS3 or retrograded resistant starch), [9] as in cooked and cooled cereals and potatoes (e.g., potato salad).
Damaged starch can be produced, for example, during the wheat milling process, or when drying the starch cake in a starch plant. [5] There is an inverse correlation between gelatinization temperature and glycemic index. [4] High amylose starches require more energy to break up bonds to gelatinize into starch molecules.
Starch hydrolyses during roasting under acidic conditions, and short-chained starch parts partially rebranch with α-(1,6) bonds to the degraded starch molecule. [5] See also Maillard reaction . Dextrins are white, yellow, or brown powders that are partially or fully water-soluble, yielding optically active solutions of low viscosity .
Modified starch may also be a cold-water-soluble, pregelatinized or instant starch which thickens and gels without heat, or a cook-up starch which must be cooked like regular starch. Drying methods to make starches cold-water-soluble are extrusion , drum drying , spray drying or dextrinization .
Cooking takes place within the extruder, where the product produces its own friction and heat due to the pressure generated (10–20 bar). The process can induce both protein denaturation and starch gelatinization under some conditions. Many food extrusion processes involve a high temperature for a short time. [1]
Discover the latest breaking news in the U.S. and around the world — politics, weather, entertainment, lifestyle, finance, sports and much more.
The first step in blanching green beans Broccoli being shocked in cold water to complete the blanching. Blanching is a cooking process in which a food, usually a vegetable or fruit, is scalded in boiling water, removed after a brief timed interval, and finally plunged into iced water or placed under cold running water (known as shocking or refreshing) to halt the cooking process.