Food Tests Flashcards
What is the Benedicts test?
The test that is carried out to test for sugars
How do you carry the Benedicts test out?
Prepare a food sample and transfer 5cm(3) to a test tube
Prepare a water bath so it is set to 75*C
Add Benedicts solution to the test tube using a pipette
Place the tube in the water bath using a test tube holder and leave it in the for 5 minutes
Make sure it is pointing away from you
If the food contains sugar the solution will change from blue to green to yellow to brick red depending on how much sugar is in the food
What is the iodine test
It is the test to see if there is starch
How do you carry the iodine test out
Make a food sample and transfer 5cm(3) of it to a test tube
Add a few drops of iodine and gently shake the tube to mix it
If there is starch the colour will change from browny orange to blue or black
What is the biuret test
It is the test to see if there are proteins
How do you carry the biuret test out
Prepare a sample of your food and add 2cm(3) of it to a test tube
Add 2cm(3) if biuret solution you the sample and mix it by gently shaking it
It is has protein it will change from blue to purple
If not it will stay blue
What is the Sudan III test
The test to see if there are Lipids
How do you carry out the Sudan III test
Prepare a sample of food and add 5cm(3) of it to a test tube
Use a pipette to add 3 drops of the Sudan stain solution to the tube and gently shake it to mix it
If there are lipids the mixture separates into 2 layers the top layer will be bright red
Name the chemical that you would use to test a sample for the presence of starch
The Iodine Test
