Which of the following can be used as food preservative ?

Options

A. Vegetable oil
B. Table salt
C. Sodium benzoate
D. All of these

Answer

To determine which of the following can be used as food preservatives, we need to understand what food preservatives are and how they function.

### Step-by-Step Solution:

1. **Definition of Food Preservatives**:
- Food preservatives are substances added to food to prevent spoilage caused by microbial growth or chemical changes. They help extend the shelf life of food products.

2. **Function of Food Preservatives**:
- They work by either killing or inhibiting the growth of bacteria, molds, and yeasts that can spoil food.

3. **Identifying Common Food Preservatives**:
- Common examples of food preservatives include:
- **Vegetable Oil**: Often used in food products to create a barrier against oxygen and moisture, which can help prevent spoilage.
- **Table Salt**: Salt is a traditional preservative that draws moisture out of food, creating an environment that is inhospitable to bacteria.
- **Sodium Benzoate**: This is a widely used chemical preservative that is effective against yeast, mold, and some bacteria.

4. **Conclusion**:
- Based on the information, all of the options provided (vegetable oil, table salt, and sodium benzoate) can be used as food preservatives.

### Final Answer:
All of the following can be used as food preservatives:
- Vegetable oil
- Table salt
- Sodium benzoate