1. Food tests

2. The food groups
Protein
Sugar
Starch
Fats and oils

3. Benedict's Test for sugar
Mash food up
Put in a test tube with Benedict’s solution
Heat in a water bath
Blue = no sugar
Orange = sugar

4. Biuret test for protein
Mash up the food to increase the surface area
Put a small quantity in a spotting tile
Add Biuret solution
Wait for a colour change

5. Iodine starch for starch
Mash the food up or chop into small pieces
Put a small piece in a spotting tile
Add a few drops of iodine
Look for a colour change
Brown = no starch
Black = starch

6. Alcohol test for fats and oils
Crush the food sample and put in a dry test tube.
Add ethanol to about 2 cm3 above the level of the sample and shake thoroughly.
Allow the solid to settle (about 3 min) to allow the fat to be extracted.
Decant (pour off) the ethanol into another test tube.
Add 2 cm3 of water to the second test tube
A white cloudy emulsion means fat is present

7. What do we know about school dinners?
Use the information you have learned about school dinners from your practical
Write a Facebook review on the ability of the dinners to contribute to a balanced diet
What have we not tested for?