Emulsifiers: Mending the Differences in Our Foods

Eggs Benedict is a brunch staple, and what makes or breaks the plate is—you guessed it—the Hollandaise sauce. This personal favorite is a combination of egg yolk, butter, water, and lemon juice or vinegar, making for the ultimate emulsion. What’s an emulsion, you may ask? It’s a common component of many of the foods we eat, and while not everyone is a food scientist, there are a few interesting things you might be curious to know about emulsifiers in our food.

What are emulsifiers?

Emulsifiers are found in many food products we buy at the grocery store. Beverages, milk, ice cream, and dressings often feature emulsifiers as additives to keep the mixture of ingredients stable. What exactly do we mean by that? Well, have you ever tried mixing together oil and vinegar for a simple salad dressing? For a short time, the two may appear homogenously mixed, but after a few minutes they are completely separated. Emulsifiers keep two components that normally do not mix well together from separating. Because oil and vinegar are so chemically different, they can often be challenging to mix. As food scientists, if we want to overcome this challenge, we can add an emulsifier. Said in a different way? If water and oil were a fighting couple, an emulsifier would be the therapist that mends their relationship. Specifically, food scientists and producers use continuous stirring and sometimes heat to add emulsifiers to two previously unmixable components—helping to keep them together over the course of the final product’s lifetime.

What foods contain emulsifiers?

Emulsifiers can either be naturally present or added as additional ingredients. In the case of the highly stable emulsion of mayonnaise, an egg yolk protein called lecithin aids in stabilizing the oil, egg, and lemon juice mixture that is the foundation of mayonnaise. Lecithin is an example of a naturally present emulsion. In contrast, soy lecithin (same protein, difference source) may be added to packaged salad dressing during manufacturing to accomplish the exact same objective.

Ice cream is perhaps one of the most beautifully complex emulsions out there. In case you aren’t an expert on my favorite product, ice cream is a homogenous mixture of air, sugar, fat globules, and ice crystals. Without the fine distribution of air, ice cream would be a solid block. If the fat globules were not distributed, it wouldn’t melt in your mouth (a common issue with non-fat ice creams). And we all know what horrors occur when ice cream is freezer-burnt—an unfortunate condition caused by the conglomeration of ice crystals. The bottom line? It is essential for ice cream to be properly mixed, and adding emulsifiers guarantees a great end-product.

Another natural example that goes way back? Milk, which is an emulsion of protein solids, butterfat, and water. The emulsifier here is in the milk fat. A more modern example? A hot dog’s filling is an emulsion of fat, water, and meat.

Do we need emulsifiers?

Sometimes emulsifiers are used simply to improve the quality of foods—as in the case of salad dressings. Other times, they are essential ingredients for creating the tasty product everyone expects—as is the case with ice cream. Emulsifiers are also critical to add to gluten-free baked goods because these products often have difficulty standing up to their gluten-rich counterparts. When we improve the quality of foods with the help of additives like emulsifiers, we in turn can extend their shelf life—an effective means of reducing food waste.

Are they safe?

Yes. The U.S. Food and Drug Administration (FDA) confirms the safe use of the emulsifiers used in our food and beverage supply. All proposed emulsifiers must pass a rigorous evaluation in order to receive a “generally recognized as safe” (GRAS) certification by the FDA.

How are emulsifiers listed on food labels?

Let’s look at the ones you’ll most likely see on the ingredient labels of your favorite foods. Lecithin is found in egg yolks and acts as an emulsifier in sauces and mayonnaise. Lecithin also can be found in soy and can be used in products like chocolate and baked goods. Other common emulsifiers include sodium stearoyl lactylate, mono- and di-glycerols, ammonium phosphatide, locust bean gum, and xanthan gum.

In conclusion

Go forth and enjoy emulsions! With your newfound knowledge of how they work, you can better appreciate your favorite well-mixed vinaigrette dressing and the excellent smoothness of ice cream as it melts in your mouth.

Written by Jacob Farr and Edward Orzechowski.