Methods of Preparation of Emulsions

A so-called emulsion is made of two immiscible liquid phases that form globules dispersed in their respective liquid phases, which are stabilized by a third matter called an emulsifying agent.

Methods of preparation of the emulsion

A dispersion of two liquids consisting of globules of one liquid over another is called an emulsion. The process of dispersion is generally used to prepare emulsions. A colloid mill or a similar device is usually used to pass through a mixture of two liquids along with an emulsifier. Shearing forces are used to break down one of the liquids in the emulsion into small globules due to the presence of the emulsifier.

Using the continental method, what is usually acacia (gum) and oil are combined with water to form the initial or primary emulsion. There are two types of continuous phases: oil-in-water (O/W) and oil-in-water (W/O), depending on whether the continuous phase consists of water or oil. The figure illustrates another method of dispersing liquids by forcing them through a capillary and injecting them directly into dispersion mediums containing emulsifiers.



An emulsion is formed as a result of the dispersion phase breaking down under pressure in the nozzle. It is also possible to dissolve the emulsifier in the dispersed phase. As an extreme example, milk is most commonly used as an emulsion since small fat globules are dispersed in water and protein is the major stabilizing agent.

Emulsion preparation methods:

• Wet gum method
• Dry gum method
• Electrical method
• Nascent soap method or (Bottle method)

Emulsions can be prepared by either drying them out or wetting them out

1. Emulsions are prepared by making a primary emulsion that is creamy, thick, and stable. Oil, acacia, and water are the components of the primary emulsion.
2. Diluting with other substances

Example
Primary emulsion
Calculations -
Amount of acacia – ½ × amount of volatile oil
Amount of acacia – ½ × amount of fixed oil
Normally, water taken for the formulation of the emulsion is always double the amount of acacia taken.

1. Dry gum method

• Mix the acacia powder with the oil and dry mortar.
• Stir vigorously until the primary emulsion forms in the mortar after adding water. Add more water as necessary until the primary emulsion becomes thick and is ready. When the primary emulsion is formed, it crackles.
• Add the liquid ingredients to the final volume to calculate the vehicle remaining.
• Three steps are needed: Dilute the primary emulsion, clean the mortar and pestle, and complete the emulsion using the remaining parts of the vehicle.

2. Wet gum method

• Here, the order of mixing is different: The acacia is first mixed with water, and then the water is triturated rapidly to produce mucilage.
• Adding oil in small portions to the mucilage (gradually) is based on a dry measuring cylinder. An emulsion of thick primary thickness must be constantly triturated after each addition.
• In terms of continental methods, nothing has changed.

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