Biology food tests

Question 1

How to prepare food solution?

Answer 1

Crush food using pestle and mortar

Add a few drops of water and mix well

Question 2

What is the special type of water that contains no other chemical substances(pure water)?

Answer 2

Distilled water

Question 3

How to test for starch (Iodine solution which is orange-yellow)?

Answer 3

Add a few drops of iodine solution to the food solution

If the solution turns dark blue-black colour, the food contains starch

Question 4

How to test for solid lipids (piece of filter paper)?

Answer 4

Rub some food onto a piece of filter paper

Hold the paper up to a light and if the paper is translucent, the food contains lipids

Question 5

How to test lipids for liquid lipids(ethanol that is colourless)?

Answer 5

Add a few drops of ethanol to your food solutions
Shake the test tube and leave for a minute
Pour ethanol into a test tube and leave for a minute
Pour ethanol into a test tube of water
If the solution turns cloudy, the food contains lipids

Question 6

How to test for sugars (Benedict’s solution which is blue)?

Answer 6

Add a few drops of Benedict’s solution to your food solution
Heat the test tube in the wet bath
If the solution turns orange-red, the food contains sugars

Question 7

How to test for protein (copper Sulfate which is pale blue and sodium hydroxide which is a colourless Liquid)?

Answer 7

Add a few drops of copper update into the food solution
Add a few drops of sodium hydroxide solution
If the solution turns purple, the food contains protein