Correct Option
The correct option isPreserve the produce by inhibiting bacterial growth
Explanation
The preservation of food items like raw mangoes and tamarind through salting is based on the principles of osmosis and plasmolysis. This method creates an environment unsuitable for microbial survival, thereby extending the shelf life of the produce.
Mechanism of Action:
- Hypertonic Environment: Adding a high concentration of salt to the produce creates a hypertonic solution outside the microbial cells (bacteria or fungi) that may be present.
- Exosmosis: Due to the concentration gradient, water moves out of the microbial cells into the external environment. This process is known as exosmosis.
- Plasmolysis: The loss of water causes the protoplasm of the microbial cells to shrink away from the cell wall. This state, called plasmolysis, inhibits metabolic activities and leads to the death of the microorganism.
- Reduction of Moisture: Salting also draws moisture out of the food item itself, reducing the water activity ($a_w$) available for microbial growth.
While salting may alter texture or taste, its primary scientific purpose in this context is to prevent spoilage by inhibiting the growth of bacteria and fungi.
Key Takeaway
Salting acts as a preservative by creating a hypertonic environment that induces plasmolysis (shrinkage of protoplasm) in bacterial and fungal cells, leading to their death.