T4 W5 (18.3.24) RM

Question 1

Food tests for Carbohydrates- Glucose:

What is the chemical used?

Answer 1

Benedict’s solution

Question 2

Food tests for Carbohydrates- Glucose:

What is the colour change?

Answer 2

From blue to either ‘brick red’, green or yellow

(The colour depends on how much Glucose is present)

Question 3

Food tests for Carbohydrates- Glucose:

What is the procedure?

Answer 3

1- add the solution
2- heat in a hot water bath for approx. 5 mins

Question 4

Food tests for Carbohydrates- Starch:

What is the chemical used?

Answer 4

Iodine

Question 5

Food tests for Carbohydrates- Starch:

What is the colour change?

Answer 5

From orange to blue/ black

Question 6

Food tests for Carbohydrates- Starch:

What is the procedure?

Answer 6

Just drop in chemical in

Question 7

Food test for Lipids:

What are the chemicals used?

[2 marks]

Answer 7

Either Sudan (III)
or
Ethanol

(Ethanol is what we use to do the experiment at school)

Question 8

Food test for Lipids:

What is the colour change for Sudan (III)?

Answer 8

From red to a layer of red just ontop of the sample

Question 9

Food test for Lipids:

What is the colour change for ethanol?

Answer 9

Clear to a milky white emulsion

DO NOT describe it as cloudy (idk why tho 🤷‍)

Question 10

Food test for Lipids:

What is the procedure (when using ethanol)?

Answer 10

1- Add ethanol
2- Shake
3- Add water
4- Shake

Question 11

Food test for Proteins:

What is the chemical used?

Answer 11

Biuret

Question 12

Food test for Proteins:

What is the colour change?

Answer 12

From blue to purple

Question 13

Food test for Proteins:

What is the procedure?

Answer 13

Just drop the chemical in

Question 14

What can you first do to the sample before conducting a test?

Answer 14

Use a mortar and pestle to break the sample down (and add distilled water?)