Biochemical Food Tests

Question 1

What reagent is used for test for reducing sugars?

Answer 1

Benedict’s reagent

Question 2

Does benedict’s test require heating?

Answer 2

Yes

Question 3

What is the colour change in the reducing sugar benedict’s test?

Answer 3

Blue to red

Question 4

What is the method of testing for non-reducing sugars?

Answer 4

Benedict’s normal test
Using the solutions that tested negative:
Then add HCl and heat again
Add sodium hydrogen carbonate
Add benedict’s again and heat
Should be blue to red colour change

Question 5

What 3 reagents are used in the test for non-reducing sugars?

Answer 5

Benedicts
HCl
NaHCO3 - sodium hydrogen carbonate

Question 6

What is the regnant used to test for starch?

Answer 6

Iodine

Question 7

Does the test for starch require heating?

Answer 7

No

Question 8

What is the colour change for the test for starch?

Answer 8

Orange-brown to blue-black

Question 9

What reagent is used to test for proteins?

Answer 9

Biuret reagent

Question 10

Does the test for proteins need to be heated?

Answer 10

No

Question 11

What is the colour change for proteins test?

Answer 11

Blue to lilac

Question 12

What is the method for testing for lipids?

Answer 12

Add ethanol to test tube
Shake
Add water
A cloudy white emulsion will form

Question 13

Does the test for lipids need to be heated?

Answer 13

No

Question 14

What reagent is used in the test for lipids?

Answer 14

Ethanol

Question 15

What is the colour change in the test for lipids?

Answer 15

Blue solution to emulsion formed