An emulsifying agent is a substance that helps to stabilize an emulsion, which is a mixture of two or more immiscible liquids (such as oil and water) that are evenly dispersed in one another without separating. The emulsifying agent acts as a surfactant, reducing the surface tension between the two liquids and allowing them to mix together. This results in a homogenous, stable mixture that will not separate over time. Examples of emulsifying agents include lecithin, polysorbates, and glycerol monostearate.
Native starch itself cannot act as an emulsifying agent due to its low solubility in water and weak hydrophobic properties. However, modified starches with appropriate hydrophobic groups can be used as emulsifying agents in some applications.
Modified starches can act as emulsifying agents. Modified starches with hydrophilic and hydrophobic properties can stabilize oil-in-water emulsions and improve the stability of the emulsion system.
Cationic starch, esterified starch and acetylated starch are commonly used as emulsifying agents. They help to stabilize oil-in-water and water-in-oil emulsions in food, cosmetic and pharmaceutical products.