3.1.2 Food tests

Question 1

What is the food test for reducing sugars?

Answer 1

Add benedict’s solution to the food sample and heat it up in a hot water bath, the colour of the solution should turn from blue to brick red (if result is positive).

Question 2

What is the food test for non-reducing sugars?

Answer 2

Add hydrochloric acid to the food sample and then heat it up in a hot water bath, neutralise the solution with sodium hydrocarbonate.
Then add Benedict’s solution to the solution and heat it up in the hot water bath again and the colour of the solution should turn from blue to brick red (if result is positive).

Question 3

What is the food test for proteins?

Answer 3

Add biuret solution to the food sample and the colour should turn from blue to lilac (if result is positive).

Question 4

What is the test for starch?

Answer 4

Add iodine solution to the food sample and the colour should go from orange to blue-black (if the result is positive).

Question 5

What is the tests for fats?

Answer 5

Add ethanol to the food sample to dissolve the fat and then add water, a white emulsion should form (if the result is positive).

Question 6

Name 4 Reducing sugars:

Answer 6

Galactose, Glucose, fructose and maltose.

Question 7

Name a non-reducing sugar:

Answer 7

Sucrose