HORTICULTURE SCIENCE
PLANT BIO CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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There no is change of color on the bread.
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The bread will change to blue-black.
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The bread will dissolve.
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The bread will change to brown color.
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Detailed explanation-1: -Iodine is a common indicator to test for the presence of starch. The light orange-brown colour Iodine solution turns blue-black in colour when it reacts with starch. This indicates the presence of carbohydrates in the food item to which iodine solution was added.
Detailed explanation-2: -Iodine solution is used to test the presence of starch in food. 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, like bread. The colour of bread changes to a deep blue.
Detailed explanation-3: -Amylose present in starch is the reason for change in its colour to blue black. Iodine is not soluble in water so it is dissolved along with potassium iodide that forms a triiodide molecule which enters the helical structure of amylose and changes the colour of starch.
Detailed explanation-4: -Iodine will change from an orange/brown colour to blue/black if starch is present. This happens when the starch molecules form a spiral and help the iodine molecules to line up.
Detailed explanation-5: -Using an iodine solution, you can test for the presence of starch. When starch is present, the iodine changes from brown to blue-black or purple.