NURSING ANM AND GNM

Detailed explanation-1: -Amylose in starch is responsible for the formation of a deep blue color in the presence of iodine. The iodine molecule slips inside of the amylose coil. Iodine-KI Reagent: Iodine is not very soluble in water, therefore the iodine reagent is made by dissolving iodine in water in the presence of potassium iodide.

Detailed explanation-2: -Iodine Test Using iodine to test for the presence of starch is a common experiment. A solution of iodine (I2) and potassium iodide (KI) in water has a light orange-brown color. If it is added to a sample that contains starch, such as the bread pictured above, the color changes to a deep blue.

Detailed explanation-3: -A positive result for the iodine test (starch is present) was a colour change ranging from violet to black; a negative result (no starch) was the yellow colour of the iodine solution.

Detailed explanation-4: -Since starch has amylose which forms a helical chain, the iodine molecules can be trapped inside it. And this gives bluish-black coloration on the Iodine test. Similar results are obtained for dextrin (color: black) and glycogen (color: reddish-brown).

Detailed explanation-5: -Amylose constitutes 5–35% of most natural starches and has a major influence over starch properties in foods. Its synthesis and storage occurs within the semicrystalline amylopectin matrix of starch granules, this poses a great challenge for biochemical and structural analyses.