Text-book of medical and pharmaceutical chemistry . e formof maltose and dextrin. It forms metallic compounds with lead,lime, and barium oxides. Soluble starch is precipitated by alcoholand solutions of subacetate of lead. Starch dissolves in cold, concentrated nitric acid ; on the addi-tion of water, xyloidin, a white powder, separates. The mostcharacteristic reaction of starch is the dark blue color it formswith free iodine. This blue iodide of starch is easily decomposed,and dissociates when the solution is heated, but re-forms oncooling. 605. Dextrin, or British Gum, is an amorphous, yello
Text-book of medical and pharmaceutical chemistry . e formof maltose and dextrin. It forms metallic compounds with lead,lime, and barium oxides. Soluble starch is precipitated by alcoholand solutions of subacetate of lead. Starch dissolves in cold, concentrated nitric acid ; on the addi-tion of water, xyloidin, a white powder, separates. The mostcharacteristic reaction of starch is the dark blue color it formswith free iodine. This blue iodide of starch is easily decomposed,and dissociates when the solution is heated, but re-forms oncooling. 605. Dextrin, or British Gum, is an amorphous, yellowish-white, gum like body, readily soluble in water. It is formed byheating starch above 150° C. (302° F.), or by the first action ofmalt diastase, or hot dilute sulphuric acid upon starch. Thischange is a progressive one. When diastase or pancreatic fer-ment is added to gelatinous starch (starch paste), it is liquefied ina few moments and becomes soluble starch, which is representedby the formula, io(C,2H2oOio). This is gradually hydrated under.
Size: 1744px × 1433px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1, booksubjectpharmaceuticalchemistry
