Testing for simple sugars and complex - the Benedict's test

Aim: To test a sample 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 2ml of the sample into a test tube and then add 5 drops of Benedict's Solution.

2. Heat with a Bunsen until it changes colour. Do not boil.

Results: the colour changes by the heat

Conclusion: Changes molecule means changing colour.

Testing for Complex Sugars - the Lodine Test

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

Equipment: Test tube, food sample, iodine solution.

Method:

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

2. Add 3-5 drops of iodine and mix.

Results: the Bread changes colour - white to black to purple

Conclusion: Changes molecule means changing colour.