. Elements of modern chemistry . Fig. 127. * Metamorphoses of Starch—Dextrin.—When long heatedto 100° starch is converted into soluble starch, which yields ablue color with iodine (Maschke). Between 160 and 200° it is converted into a body which isvery soluble in water, and the solution of which is not coloredby iodine. This solution strongly turns the plane of polariza-tion to the right; hence the name dextrin given to this body,which is regarded as isomeric with starch, (C^H^^O^). A veryconcentrated solution of dextrin has the appearance of a solu-tion of gum. It is used as a mucilag
. Elements of modern chemistry . Fig. 127. * Metamorphoses of Starch—Dextrin.—When long heatedto 100° starch is converted into soluble starch, which yields ablue color with iodine (Maschke). Between 160 and 200° it is converted into a body which isvery soluble in water, and the solution of which is not coloredby iodine. This solution strongly turns the plane of polariza-tion to the right; hence the name dextrin given to this body,which is regarded as isomeric with starch, (C^H^^O^). A veryconcentrated solution of dextrin has the appearance of a solu-tion of gum. It is used as a mucilage for labels, and for thepreparation of immovable surgical dressings. Alcohol added to a solution of dextrin precipitates the lattersubstance in the form of flakes. Subacetate of lead does not 636 ELEMENTS OF MODERN CHEMISTRY. precipitate dextrin, a character which permits the latter bodjto be distinguished from gum arabic. When starch is boiled with water containing a few per cent,of sulphuric acid, it is first converted
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