Question

Which of the following substances are not used as humectants in emulsions?

• A. Propylene glycol
• B. Sorbitol
• C. Tocopherol
• D. Glycerol

Answer 1

The Correct Option is B

The question asks us to identify which of the following substances is not typically used as a humectant in emulsions. A humectant is a substance that helps retain moisture. Let's evaluate each option:

1. Propylene glycol: This is commonly used as a humectant. It attracts water and is frequently used in cosmetic and pharmaceutical formulations to maintain moisture.
2. Sorbitol: While sorbitol can be used as a humectant due to its hygroscopic nature, it is less commonly used in emulsions compared to propylene glycol or glycerol. Its primary use is often in oral care products and as a sugar substitute.
3. Tocopherol: This is vitamin E, and its primary function is as an antioxidant rather than a humectant. It is used in formulations to prevent oxidation and extend shelf life.
4. Glycerol: Also known as glycerin, it is a widely used humectant. It can draw moisture into the skin and maintain hydration in emulsions and other formulations.

Given the options, sorbitol is less commonly used in emulsions specifically as a humectant compared to the others. While it does have humectant properties, its role in emulsions is atypical relative to glycerol and propylene glycol.

Therefore, the correct answer is Sorbitol.