Question

Spoilage of oil can be detected by which fatty acid__________.
A. Oleic acid.
B. Linolenic acid
C. Erucic acid.
D. None of these

Answer 1

Hint: A fatty acid, in general, is made up of a straight chain with an even number of carbon atoms, hydrogen atoms operating the length of the chain. At one verge, and a carboxyl group (COOH) at the further edge. It's because of the carboxyl group that it's an acid (carboxylic acid).

Complete explanation:
Option A: Oleic acid is a type of fatty acid found in a variety of animal and vegetable fats and oils. While commercial samples can be yellowish, it is an odourless and colorless oil. Oleic acid is utilized in pills as an excipient and aerosol commodities as an emulsifying or solubilizing agent.
Hence, option A is incorrect.
Option B: Linolenic acids are used in beauty goods like soaps, emulsifiers, and quick-drying oils. It aids in the reduction of acne and the preservation of moisture, among other things. Linoleic acid is an important fatty acid for infants' growth and development. It's used in margarine, animal feeds, soaps, and pharmaceuticals.
Hence, option B is incorrect.
Option C: Erucic acid is an omega-9 monounsaturated fatty acid. It is found in higher concentrations in oils and is quickly degraded by microorganisms, resulting in a foul odour. As a result, its presence is used to detect oil spoilage.
Hence, option C is the correct answer.
Option D: Since the option erucic acid is the right answer. That means the option 'none of these' is not true.
Hence, option D is incorrect

Hence, option C is the correct answer.

Note:
The free fatty acids are used to assess the degree of hydrolytic spoilage of oils (also known as hydrolytic rancidity). The acidity of the oil, also known as the acid number or acid degree, determines the amount of free fatty acids present. The hydrolysis of triacylglycerol causes the oil to become acidic. Lipase enzymes from bacteria are usually responsible for hydrolytic rancidity. The harsh and unpleasant flavors of sour milk are caused by short-chain fatty acids like butyric. When foods are cooked at high temperatures, a chemical process called hydrolytic rancidity may occur (frying).