Food additives: emulsifier

DEFINITION

Food emulsifiers, also called emulsifiers, are surfactants that act as a boundary between two immiscible liquids (such as oil and water), allowing them to mix into a stable emulsion. Emulsifiers can also reduce viscosity, control crystallization and prevent separation.

FUNCTION, NAME AND LABEL

Emulsifiers produce two types of emulsions: oil droplets dispersed in water or water droplets dispersed in oil. In the emulsion, there is a continuous phase and a dispersed phase. In oil-in-water emulsions, the continuous phase is water and the dispersed phase is oil; in contrast, in water-in-oil emulsions, the oil is the continuous phase.

The emulsion can also be prepared by applying mechanical force from a stirrer or homogenizer, which breaks down the dispersed phase into tiny droplets suspended in the continuous phase.

Low-fat spreads, ice cream, margarine, salad dressings and many other cream sauces are kept in a stable emulsion by adding emulsifiers. These additives are also widely used in other foods, such as peanut butter and chocolate.

Emulsifiers enhance the structure of baked goods by increasing the whipping power of the batter, conditioning the dough and helping foods such as pasta to be more resistant to overcooking.

Commonly used emulsifiers in modern food production include mustard, soy and egg lecithin, mono and diglycerides, polysorbate, carrageenan, guar gum, and rapeseed oil.

Lecithin in egg yolk is one of the most powerful and oldest animal-derived emulsifiers used to stabilize oil-in-water emulsions such as mayonnaise and hollandaise.

The law requires emulsifiers to be included in the list of food ingredients.

SUPERVISE

The safety of emulsifiers is carefully regulated and tested by the US Food and Drug Administration. Emulsifiers can be found on the recognized safe or GRAS lists and are allowed to be present at precise levels in certain types of foods and beverages.

However, the FDA process does not consider the personal diets of people who rely heavily on packaged foods.

Although GRAS substances must technically meet the same safety standards as approved food additives, the GRAS process has evolved into a voluntary notification procedure, and many GRAS additives have not yet been tested.

Congress defines safety as "reasonable certainty that the use of additives will not cause harm." The additives have never been permanently approved. The FDA continuously reviews the safety of approved additives based on the best scientific knowledge to determine whether the approval should be modified or withdrawn.

As early as 2017, the FDA reviewed and confirmed the safety of carrageenan, an emulsifier whose safety has been questioned.

SAFETY

Most of the concerns about food additives are for synthetic ingredients added to food.
The published peer-reviewed intervention studies involving emulsifiers are limited to animals. A mouse study published in the journal Nature in 2015 found that two common synthetic emulsifiers, carboxymethyl cellulose (CMC) or polysorbate 80 (P80), caused weight gain and inflammation after 12 weeks And low-grade symptoms of metabolic syndrome.

Some emulsifiers are suspected of acting like detergents, disrupting friendly bacteria in the microbiota, causing low-grade inflammation and leading to overeating.

A follow-up study published in Cancer Research by Gewirtz, professor of biomedical sciences at Georgia State University, and his colleagues showed that changes in intestinal bacteria caused by emulsifiers may cause bowel cancer. A small clinical trial is currently underway to evaluate the role of CMC in humans.

In response to the safety of certain emulsifiers, a team of FDA scientists reviewed the emulsifiers commonly used in seven foods, including CMC and P80, to determine whether these ingredients pose any risks to human health. The results of their study published in 2017 confirmed that emulsifiers are still safe at estimated exposure levels.

FINAL THOUGHTS

Food additives, including emulsifiers, play an important role in our food supply. Consumers who are concerned about these ingredients are encouraged to read labels and eat more minimally processed foods.