Topic B2 Food Tests

Question 1

What is the Benedict’s test used for?

Answer 1

To test for reducing sugars

Question 2

What is Iodine Solution to test for?

Answer 2

To test for starch

Question 3

What is Sudan III to test for?

Answer 3

To test for lipids

Question 4

What is the Buiret Test used for?

Answer 4

To test for proteins

Question 5

Describe the process of the Benedict’s test

Answer 5

Prepare water bath to 75 degrees C
Take 5cm^3 of food sample and transfer to test tube
Add 10 drops of Benedicts using a pipette
Place test tube in the water bath
Leave for 5 minutes
If there is no colour change = no sugar is present
If there is a colour change = sugar is present

Question 6

Describe the process of the Iodine Test

Answer 6

Take 5cm^3 of food sample and transfer to test tube
Add a few drops of iodine solution
Shake
If starch is present = Turn blue black
If starch isnt present = No colour change from orange-brown

Question 7

Describe the process of the Biuret Test

Answer 7

Take 2cm^3 of food sample and transfer to test tube
Add 2cm^3 of biuret solution to test tube
Shake
If proteins are present = Turn to purple

Question 8

Describe the process of Sudan III Test

Answer 8

Take 5cm^3 of UNFILTERED food sample and transfer to test tube
Add 3 drops of Sudan III solution
Shake
If the layer above is stained = lipids