Back to the Basics: Types of Emulsifiers and Their Applications

Written by Hopeton Watson, Application Development Specialist for Univar Solutions Food Ingredients

When looking at the science behind food, sometimes the array of additives we use can become convoluted. However, when it comes to seamless mixing there is one key ingredient that prevents separation—an emulsifier.

At a young age, we learn that oil and water just don’t mix. No matter how much you stir, small concentrated oil droplets will still float to the top completely separated from the water. So what happens when a recipe calls for the mixing of such ingredients?

That’s where emulsifiers come in.

The Science Behind Blending

In basic terms, an emulsifier is something that causes less friction between oil molecules and water molecules. The molecules in this additive has two portions; one that is attracted to oils and another that is attracted to water. These portions will orient to what they are attracted to and ultimately create an evenly distributed substance of both ingredients, aka emulsion.

Emulsion can also take place by applying mechanical force from a blender or homogenizer, which breaks down tiny oil droplets that become suspended in the water phase. For example, mayonnaise is a mixture of egg, oil and lemon juice. An emulsifier lecithin is found in the egg yolk that stabilizes the mixture and prevents separation.

Ice cream is another complex emulsion of sugar, fat globules and ice crystals where air is dispersed throughout the mixture. Emulsifiers (mono and diglycerides) are used to develop the appropriate fat structure and air distribution network to aid in smooth eating and good meltdown characteristics.

Common Emulsifiers & Applications

So now that we know how they work, you may be wondering what are some other common emulsifiers that are used in today’s food industry. Some of the most common additives are classified as:

• Lecithins – are mixtures of fats that are usually extracted from sources such as egg yolk, soybeans, sunflower and canola.
• Mono and diglycerides – are made from natural fatty acids, glycerol and an organic acid.
• Polysorbates – a viscous water soluble yellow liquid derived from etoxilated sorbitan esterified with fatty acids
• Sodium stearoyllactylate (SSL) – a food additive used to improve the mix tolerance and volume of processed foods.

To see a full list of the emulsifiers carried by Univar Solutions, download our Food Ingredients Product Overview and gain insight into our industry-leading product selection and availability.

Emulsifiers also aid in a wide range of functions within food products, including:

• Emulsification
• Starch Complexing
• Protein interaction
• Aeration
• Crystal Modification
• Lubrication and Processing Aid 

Emulsification

Many processed foods are emulsions (margarines, nondairy creamers, cake batters and beverages). Non-Dairy Creamer is an emulsion of fat in water.

Starch Complexing

Staling is a chemical and physical process in baked products. In bread it caused drying out of the crumb. This results in stale bread becoming leathery, hard texture, loss of aroma and freshness. Emulsifiers act as surface active agents and help to retard staling.

Protein Interaction

Emulsifiers can react with proteins in a variety of foods. Protein interaction can affect volume in baked foods as well as mouth feel in sauces and gravies.

Aeration

Aerated foods (cake batters, creamers) are complex emulsion. They are oil in water emulsions that incorporate and require the stabilization of air cells. Emulsifiers are generally employed to strengthen the air cell of these emulsions.

Crystal Modification

Emulsifiers can influence the appearance and texture of chocolate and coatings by maintaining gloss and snap. Chocolate Blooms are either of two types of whitish coatings that can appear on the surface of chocolate. Fat Bloom is caused by changes in fat crystals in the chocolate and Sugar Bloom due to the action of moisture on the sugar. Both blooms can damage the appearance of chocolate and limit its shelf life. Certain emulsifiers can delay and retard the process resulting in increased shelf life.

Lubrication

Mono and diglycerides, as well as distilled monoglycerides, are used in extruded products like pasta and breakfast cereals as lubricants and processing aids. These emulsifiers can provide release from packaging or equipment. 

To determine what emulsifier is best for your particular application, it may take some extra research or industry expertise. Univar Solutions provides an expansive product line as well as formulation expertise across a broad range of food applications. Our team of dedicated specialists can provide application development and support from market trend research to product formulation. Contact us today to learn how we can enrich your food and beverage applications.