Milk protein is curdled into calcium paracacinate by-

Options

A. Maltose
B. rennin
C. Trypsin
D. Lactose

Answer

**Step-by-Step Solution:**

1. **Understanding the Context**: The question asks about the process of curdling milk protein into calcium paracacinate. This process primarily occurs in young mammals that consume milk.

2. **Identifying the Milk Protein**: The main protein in milk that is relevant to this process is called caseinogen.

3. **Role of Enzyme Renin**: In young mammals, an enzyme known as renin is responsible for curdling caseinogen. Renin is initially present in an inactive form called pro-renin.

4. **Activation of Renin**: The activation of pro-renin occurs in the presence of gastric hydrochloric acid (HCl) which is secreted in the stomach.

5. **Curdling Process**: Once activated, renin acts on caseinogen, leading to its curdling into calcium paracacinate. This is a crucial step for the digestion of milk protein.

6. **Further Digestion**: After curdling, the calcium paracacinate can be further hydrolyzed by the enzyme pepsin, which breaks it down into smaller peptides known as peptones.

7. **Conclusion**: Therefore, the enzyme responsible for curdling milk protein into calcium paracacinate is renin.

**Final Answer**: Milk protein is curdled into calcium paracacinate by renin.

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