Tag: chemicals in food

Questions Related to chemicals in food

Modern oil-based paints contain oils that can dry to form strong, adhesive films by cross-linking of fatty acid chains. Some of these drying oils' are mentioned here. Can you pick the false one?

  1. Linseed oil

  2. Turpentine oil

  3. Soyabean

  4. Castor oil


Correct Option: B
Explanation:

Drying oils are prone to hardening upon exposure to air, due to free radical base polymerization, thus forming a flexible, transparent and waterproof film. This property is exhibited by linseed, turpentine and soybean oils. 

Stearic acid is.

  1. An unsaturated fatty acid

  2. A saturated fatty acid

  3. Essential fatty acid

  4. A simple lipid


Correct Option: B

________ act as protective agent on the surface of animals and plants.

  1. Carbohydrates

  2. Vitamins

  3. Nucleic Acids

  4. Wax


Correct Option: D
Explanation:

Wax act as a protective agent on the surface of animals and plants. It protects animals and plants from excessive loss of moisture. It protects the plants and fruits from becoming infected with fungi and bacteria.


Wax contains esters of long chain fatty acids and long chain alcohols or sterol.

Hence, option D is correct.

High molecular weight alcohols are present in:

  1. waxes

  2. fats

  3. oils

  4. phospholipids


Correct Option: A
Explanation:

waxes are monoglycerides, these are form by the condensation reaction between monohydroxy alcohol and fatty acid, this is the high molecular weight compound.

Example- Bee wax 
( Hexacosyl palimitate $\rightarrow$ Hexacosyl alcohol+ Palmitic acid)
$C _{26}H _{53}OH + C _{15}H _{31}COOH \overset{-H _2O}\rightarrow C _{26}H _{53}COOC _{15}H _{31}$ 

Four oils $A, B, C$ and $D$ have the following values of melting points.
(a) $258$ K (b) $273$ K (c) $295$ K (d) $303$ K
Among these, which oil is prohibited from consumption by cardiac patients?

  1. a

  2. b

  3. c

  4. d


Correct Option: D
Explanation:

The oils having higher unsaturation in the fatty acid component have very low melting points. Hence, on the consumption of these oils there is less chance of blockage of blood vessels. The saturated oils have higher melting points and they get solidified easily. Therefore they block the blood vessels and so are prohibited from consumption by cardiac patients. Hence oil D is prohibited from consumption by cardiac patients.