Spoilage of oil can be detected by which fatty acid ?

Options

A. Oleic acid
B. Linolenic acid
C. Linoleic acid
D. Erucic acid

Explanation

To determine which fatty acid can be used to detect spoilage in oil, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Oil Composition**:
- Oils, particularly refined oils, are primarily composed of unsaturated fatty acids. These fatty acids contain one or more double bonds in their carbon chain.

2. **Identifying Common Oils**:
- Common refined oils include groundnut oil, coconut oil, soybean oil, and sunflower oil. These oils are derived from plant sources.

3. **Recognizing Spoilage Indicators**:
- When oils spoil, they often emit a bad odor. This odor is a key indicator of spoilage.

4. **Identifying the Responsible Fatty Acid**:
- The bad smell associated with spoiled oil is primarily due to the presence of erucic acid. Erucic acid is an unsaturated omega-9 fatty acid that is particularly susceptible to degradation by microorganisms.

5. **Understanding Other Fatty Acids**:
- Other fatty acids mentioned, such as oleic acid, linoleic acid, and linolenic acid, are also unsaturated but do not contribute to the spoilage odor in the same way as erucic acid.
- Oleic acid has one double bond, linoleic acid has two double bonds, and linolenic acid has three double bonds, but none of these are primarily responsible for the spoilage detection.

6. **Conclusion**:
- Therefore, the fatty acid that can be used to detect spoilage in oil is **erucic acid**.

### Final Answer:
- The spoilage of oil can be detected by **erucic acid**.

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