The degree of unsaturation in a fat is estimated by

Options

A. Iodine value
B. Saponification number
C. Reichert meissl number
D. Polenske number

Answer

To determine the degree of unsaturation in a fat, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Unsaturation**:
- Unsaturation in fats refers to the presence of double bonds between carbon atoms in fatty acid chains. The more double bonds present, the more unsaturated the fat is.

2. **Identify the Measurement Method**:
- The degree of unsaturation is quantified using a specific measurement known as the iodine value (or iodine number). This value indicates how much iodine (in grams) is consumed by 100 grams of the fat.

3. **Explain the Iodine Value**:
- The iodine value is a direct measure of unsaturation because iodine reacts with the double bonds in unsaturated fatty acids. Therefore, a higher iodine value indicates a higher degree of unsaturation.

4. **Evaluate Other Options**:
- **Saponification Number**: Measures the average molecular weight of fatty acids in a fat, not unsaturation.
- **Ricord Mycel Number**: An index of the volatile acid content of a fat, unrelated to unsaturation.
- **Polanski Number**: Indicates the amount of volatile fatty acids that can be extracted through saponification, also not related to unsaturation.

5. **Conclusion**:
- Based on the understanding of the iodine value and its relationship to unsaturation, we conclude that the correct answer to the question is the iodine value.

### Final Answer:
The degree of unsaturation in a fat is estimated by the **iodine value**.

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