Food tests Flashcards
1
Q
What is the test for starch
A
Add a few drops of iodine solution to a substance
2
Q
What is the colour change if starch is present
A
Orange to blue/black
3
Q
What is the test for lipids
A
Add a few drops of ethanol to a substance, shake and allow to stand for a minute. Pour the ethanol in a test tube of water.
4
Q
What is the colour change if lipids are present
A
Colourless to cloudy
5
Q
What is the test for proteins
A
Add a few drops of copper sulphate solution and then add a few drops of sodium hydroxide solution.
6
Q
What is the colour change if proteins are present
A
Pale blue to purple
7
Q
What is the test for glucose
A
Add a few drops of Benedict’s solution to the substance. Then heat the test tube in a water bath.
8
Q
What is the colour change if glucose is present
A
Blue to orange-red
