food testing

Question 1

What is the main use of iodine in biochemical tests?

Answer 1

Iodine is primarily used to test for the presence of starch.

Question 2

True or False: The Biuret reagent is used to detect proteins.

Answer 2

True

Question 3

What color change occurs when iodine reacts with starch?

Answer 3

The solution turns blue-black.

Question 4

Fill in the blank: The Biuret test turns _______ in the presence of proteins.

Answer 4

purple

Question 5

What is the role of ethanol in biochemical tests?

Answer 5

Ethanol is used as a solvent to precipitate lipids.

Question 6

Multiple choice: Which of the following indicates a positive Biuret test? A) Blue, B) Green, C) Purple, D) Yellow

Answer 6

C) Purple

Question 7

what colour would iodine stay as if there is no starch present

Answer 7

yellow/brown

Question 8

what reagent is used to test for fats

Answer 8

ethanol

Question 9

Fill in the blank: The presence of proteins can be confirmed by the Biuret test through the formation of a _______ color.

Answer 9

purple

Question 10

Multiple choice: Which reagent is used to test for the presence of starch? A) Biuret, B) Iodine, C) Ethanol, D) Benedict’s

Answer 10

B) Iodine

Question 11

What does a negative result in the Biuret test indicate?

Answer 11

It indicates the absence of proteins.

Question 12

True or False: Ethanol can be used to test for sugars.

Answer 12

False

Question 13

What is the purpose of adding iodine to a sample in a starch test?

Answer 13

To visually confirm the presence of starch.

Question 14

Fill in the blank: The color of a positive iodine test is _______.

Answer 14

blue-black

Question 15

What is Benedict’s reagent primarily used for?

Answer 15

to test for the presence of reducing sugars.

Question 16

What colour change indicates a positive result when using Benedict’s reagent

Answer 16

The solution changes from blue to red

Question 17

How is the Benedict’s test performed?

Answer 17

The test is performed by mixing the sample with Benedict’s reagent and heating it in a water bath.

Question 18

What is the original color of Benedict’s reagent?

Answer 18

The original color of Benedict’s reagent is blue.

Question 19

whats the end colour of benedict reagent

Answer 19

brick red

Question 20

What is iodine reagent commonly used for?

Answer 20

Iodine reagent is commonly used to test for the presence of starch.

Question 21

True or False: Iodine reagent turns blue-black in the presence of starch.

Answer 21

True

Question 22

What color change occurs when iodine reagent is added to a solution containing starch?

Answer 22

The solution turns blue-black.

Question 23

Which type of carbohydrate does iodine reagent specifically react with?

Answer 23

Starch

Question 24

True or False: Iodine reagent can be used to test for proteins.

Answer 24

False

Question 25

Short Answer: What is the appearance of iodine reagent before it is mixed with starch?

Answer 25

Brown or yellow-brown

Question 26

whats biurets initial colour and what is it end results is results are positive

Answer 26

blue; lilac/purple

Question 27

What is the primary use of biuret reagent

Answer 27

To detect the presence of proteins.

Question 28

whats ethanol initial colour and what is it end results is results are positive

Answer 28

colourless to white emulsion

Question 29

what does ethanol test for

Answer 29

lipids aka fats

Question 30

what are fats made up of and its function

Answer 30

fatty acids and glycerol its function js a energy source and storage

Question 31

what are proteins made up of

Answer 31

made of amino acids

Question 32

what are carbohyrates made up of

Answer 32

simple compounds--- glucose and lactose complex ---- cellulose starch and glycogen

Question 33

whats the carbohyrates function

Answer 33

for energy and storage