With food technology training, aspiring professionals in the field gain a hands-on approach to safety and quality, and the skills to implement quality assurance and regulatory principles. As food creation is grounded in scientific processes, some of this relies on the principles of chemistry.
One process that food technology professionals should understand is emulsification. This is the process of creating an emulsion, the result of what forms when two or more immiscible liquid substances are mixed together.
An emulsion is a type of colloid, but not all colloids are emulsions. A colloid can refer to a mixture of any phases of matter, whereas an emulsion refers specifically to liquid substances. Read on to learn three facts about emulsions and the process of emulsification.
Emulsions are Formed Through Various Processes
The combination of two liquids into one solution may seem straightforward. In reality, there are several variables involved, and two liquids can come together to form an emulsion in a few different ways. For example, oil in water can form an oil-in-water emulsion. It can also come together to form a water-in-oil emulsion, or even an oil-in-water-in-oil emulsion.
Additionally, there are several different routes the process of emulsification can take.
- The interfacial tension (the force of attraction between the molecules of two fluids) can be reduced
- A film can be formed over one phase in a mixture to create evenly dispersed globules
- The viscosity of the medium can be increased, making it easier for the globules to remain suspended
Emulsions Aren’t a Total Solution for Professionals With Food Technology Training
Whichever route is taken to create an emulsion, most of them are unstable and will not mix on their own. Shake a bottle of oil and water vigorously, and for a moment the liquids will appear blended before settling back into their separation.
This temporary suspension of immiscible (not forming a homogeneous mixture together) liquids is referred to as colloidal suspension. To increase the length of time that liquids are mixed together, an emulsifier is added to the mixture.
An emulsifier, also referred to as an emulgent, is a substance that confers long-term kinetic stability to a mixture. Unfortunately, emulsions are inherently unstable, no matter how much stability is granted. Over time, they will always eventually separate. What interests students in food technology training is figuring how to confer kinetic stability for as long as possible.
Some examples of common emulsifiers in food are:
- Egg yolks
- Garlic paste
Emulsions are More Commonly Encountered Than One Might Think
Though an analysis of the process of emulsification relies on chemical principles, emulsions are relatively common in kitchens. Even without a food technology diploma, many people will have created an emulsion themselves.
Common examples of emulsions are:
In addition to conferring kinetic stability by necessity, emulsifiers are sometimes used to improve the quality or longevity of food products. Some common applications of emulsifiers are:
- In bread, emulsifiers are added to the dough to achieve larger volume, softer crumbs, and a longer shelf-life
- In chocolate, emulsifiers are added to improve consistency, so that products can be moulded into shapes and forms
- In ice cream, emulsifiers are added during the freezing process to create a smoother texture and improve the freeze-thaw stability
Do you want to enrol in food technology courses?
Contact the Academy of Applied Pharmaceutical Sciences for more information!