What Are Food Additives?

Food additives have been used for centuries to improve and preserve the taste, texture and appearance of food. Food additives and preservatives serve a variety of purposes. These include preventing foodborne illness, increasing the shelf-life of products and meeting quality standards from batch to batch.

The U.S. Food and Drug Administration (FDA) evaluates the safety of food additives and determines how they may be used. If an additive is approved, the FDA issues regulations on the types of foods it can be used in, the maximum amounts allowed and how it should be identified on food labels.

The FDA maintains a database of nearly 4,000 ingredients, titled "Substances Added to Food." Here are a few categories and ingredients commonly used in the food supply, plus what they do.

Anti-Caking Agents

Anti-caking agents may be added to powdered or fine, grainy ingredients — such as powdered milks, egg mixes, sugar, salt, flour and baking mixes — to prevent lumping, caking or sticking. These include calcium phosphates, silicon dioxide, silicates (calcium, aluminum and tricalcium) and stearic acid.

Emulsifiers

Emulsifiers are added to fat- and water-based mixtures to help keep ingredients blended. These may be from a variety of sources. Examples of emulsifiers include herbs and spices in vinaigrette dressings and egg yolk in mayonnaise.

Guar gum, made from grinding the seeds of the guar plant into powder, is used in a variety of gluten-free products. Lecithin, a protein found in egg yolk and soy, can be isolated and is used as an emulsifier in the larger food supply. Other emulsifiers include diacetyl tartaric acid ester of monoglycerides (DATEM) and sodium stearyl lactylate. These often are used in commercial bread doughs, artificial whipped creams and dried, liquid or frozen egg whites.

Food Dyes and Food Colors

While food dyes are made in a lab, food coloring may refer to either lab-made or natural food colors, such as beet juice. Both are used to make food more appealing to consumers. For example, food coloring may be used to make a strawberry flavored drink look pink or to give cheese an orange color.

Humectants

Humectants keep food moist. Common examples include glycerin, honey, sugar polyols (glycerol, sorbitol, xylitol, maltitol) and propylene glycol. Humectants often are found in candy, shredded coconut and marshmallows. It’s important to note that polyols also are used in foods as a low-calorie sweetening option, particularly sugar-free chewing gums, candies and other low-calorie foods.

pH Control Agents

Ingredients that either maintain or control the acidity of foods are known as pH control agents. These may be added to alter the texture, taste or safety of a food. Citric acid, acetic acid and sodium citrate are widely used and often are found in jams, sauces and candies. Lactic acid is used in cheese-making, and adipic acid can be found in bottled fruit-flavored drinks.

Leavening Agents

Leavening agents are incorporated into doughs and batters to increase the volume, shape and texture of baked goods. Common leavening agents include baking powder, beer, buttermilk, yeast, whey protein concentrate and yogurt. Used in a wide variety of sweet and savory products, these leavening agents can be found in cakes, cookies, breads, biscuits, scones, muffins and soda bread.

Stabilizers, Thickeners and Gelling Agents

These ingredients are widely used to improve stability and create a uniform texture in foods. They work by preventing emulsions from separating, ice crystals from forming and ingredients from settling. The starch-based category of thickeners includes arrowroot, corn, potato and tapioca. Vegetable gums include guar and locust bean gum. Common protein-based thickeners include collagen, egg whites and gelatin. Alginic acid, alginates (sodium, potassium, calcium), agar-agar and carrageenan are polysaccharides derived from algae and seaweed. Pectin is a polysaccharide originating from apple and citrus fruits and xanthan gum is obtained by fermenting a specific strain of bacteria.

To learn more about other food additive categories and particular ingredients, visit the FDA website’s Food Ingredients & Packaging section.