Which of the following is not an example of single cell protein ?

Options

A. Spirulina
B. Methylophilus methylotrophus
C. Agaricus bisporus
D. Cow's milk

Answer

To determine which of the following is not an example of single cell protein, we need to analyze each option provided:

1. **Understand the concept of single cell protein (SCP)**:
- Single cell protein refers to the protein extracted from single-celled organisms like bacteria, yeast, and algae. These organisms are cultivated in large quantities and serve as a rich source of protein, fats, carbohydrates, minerals, and vitamins.

2. **Evaluate the options**:
- **Spirulina**: This is a type of blue-green algae and is considered a single cell protein.
- **Methylophilus**: This is a genus of bacteria that can be used as a source of protein, thus it qualifies as single cell protein.
- **Methylotrophs**: These are bacteria that utilize methanol and are also considered single cell protein.
- **Agaricus bisporus**: This is a species of mushroom (commonly known as the button mushroom) which is not a single-celled organism, but it is often included in discussions about protein sources. However, it is not classified as single cell protein.
- **Cow's milk**: This is a dairy product obtained from cows, which are multicellular organisms. Therefore, it does not qualify as single cell protein.

3. **Conclusion**:
- Among the options provided, **cow's milk** is the only one that is not an example of single cell protein because it is derived from a multicellular organism (the cow).

Thus, the correct answer is **Cow's milk**.