Food tests

Question 1

Aim

Answer 1

Conduct tests for starch, sugars, proteins and lipids

Question 2

Test for starch

Answer 2

• Add a few drops of iodine solution to the food sample using a pipette
• If starch is present the solution turns from brown to blue black

Question 3

Test for sugar

Answer 3

Add an equal volume or excess Benedict solution to the food sample
Place in hot water bath
If sugar is present it will turn from blue to brick red

Question 4

Test for lipids

Answer 4

Add ethanol to food sample
If lipids are present a white emulsion is formed on the surface of the mixture

Question 5

Test for protein

Answer 5

Add a few drops of Biurets reagent to food sample
If protein is present the solution turns from blue to purple

Question 6

What is the test for lipids also known as

Answer 6

Emulsion test