Testing For Simple And Complex Sugars.

BENEDICT'S TEST

Testing for Simple Sugars

Aim: To test of food to determine whether it contains simple sugars.

Equipment: Bunsen Burner, test tube tongs, Benedict's Solution, a sample of food.

Method:

1. Place about 2 mL of the sample into a test tube and then add 5 drops of Benedicts Solution.

2. Heat with Bunsen Burner until it changes color. DO NOT BOIL

Results: A positive test for a simple sugar results in Benedict's Solution changing from an aquamarine blue color to an opaque orange color. No color change is a negative result

Conclusion: The solution changing color means that the food has simple sugars in it if not, it does not have simple sugars in it.

THE IODINE TEST

Testing for Complex Sugars

Aim: To test if a sample of food contains complex sugars.

Equipment: Test tube, food sample, iodine solution.

Method:

1. Place about 2 mL of the sample in a test tube

2. add 3-5 drops of iodine and mix

Results: If complex sugars are present, the iodine solution will change from brown to blue/black. If the iodine solution does not change color, then no complex sugars are present.