starch
Starch is a polysaccharide. Making starch is a way for all green plants to store energy. It is also the most common carbohydrate in human diet, potatoes, wheat, corn, rice, cassava and other staple foods contain a lot of starch. Pure starch is a white, tasteless, odorless powder that is insoluble in cold water or alcohol. The formula n. Starch due to intramolecular hydrogen bonds and curled into a spiral structure, can be divided into amylose (sugar starch) and amylopectin (gelatin). The former is a non-branched helix structure; the latter to 24 to 30 glucose residues to α-1,4-glycosidic bond is linked to the end of the branch at the α-1,6-glycosidic bond. Amylose in case of iodine blue, amylopectin iodine was purple. This is due to the fact that the central pores of the starch spiral are capable of allowing the iodine molecules to pass through the van der Waals force, both of which form a blue-black complex. Experiments show that the individual iodine molecules can not make the starch blue, in fact, so that the blue starch is a triiodide anion (I3-). Starch is processed in the food industry to produce a variety of sugars. Starch dissolves in warm water to produce dextrin, which can be used as a thickening agent, hardening or adhesive. The most widely used starch in the non-food industry is in the paper making process as a binder. ...