Food Tests Flashcards
How to prepare a food sample?
1)Get a small amount of food and grind it up using a Mortar and Pestle.
2)Transfer the broken up good into a beaker and add distilled water then stir it with a glass rod to dissolve the food
3) filter out the solution to get rid of the solid food
How to test for sugars?
Benedict’s test is used for sugar(1)
Prepare your food sample and transfer some to a test tube(1)
Add 10 drops of Benedict’s solution to each test tube using a pipette(1)
Place the test tube into a water bath(1)
the colour will change from blue- green or orange - red if there is a high sugar concentration (1)
How is starch tested?
Add iodine solution to the food damspel. If it turn blue-black starch is present if it turns brown-orange starch isn’t present
How to test for proteins?
Add a biuret to the sample and mix the test tube by gently shaking it. If protein is present the solution will change from blue to purple if not the solution will stay blue.
How to test for lipids?
Use a pipette to add 3 drops of Sudan III to the test tube and shake gently. This will stain lipids if lipids are present the mixture will separate into two layers the top being red.
