Humectants and Anticaking Agents


Processed foods that sit on supermarket shelves for a while would deteriorate if certain food additives were not included. Humectants and anticaking agents contribute to consumer expectations for quality and performance of favorite foods if certain food additives were not included. Humectants and anticaking agents contribute to consumer expectations for quality and performance of favorite foods.


Anticaking agents stop powders and granulated ingredients from clumping, and humectants stabilize foods through moisture control. Both food additives can be derived from natural sources or manufactured from chemical or artificial ingredients. They also are used in nonfood applications, such as cosmetics, detergents, pharmaceuticals and tobacco.

It is important to note that many food additives serve more than one role. Mannitol, for example, is an additive that functions as a humectant, nutritive sweetener and texturizer.

Functions, Names and Labeling

Anticaking agents function by absorbing excess moisture or by coating particles to make them more water repellant, which helps inhibit clumping. Added in very small amounts, these compounds prevent dry foods from sticking together, ensuring a product remains dry and free-flowing.

Humectants control water activity in foods, thus enhancing stability and viscosity, maintaining texture and reducing microbial activity. If processed foods were consumed within a few days, food additives would not be necessary; since many food products sit on shelves in stores and homes for some time, additives aid in reducing water activity while keeping foods moist and safe for a longer shelf life.


Foods that need to be kept moist risk potential bacterial growth. Moisture in food affects microbial activity, physical and sensory properties and possible chemical changes. Moisture in food can be controlled by removing it through dehydration or chemically binding it with humectants. Humectants control moisture changes caused by humidity fluctuations in processing, transit and storage on the shelf.

Dry cereal with raisins, candy with liquid centers, cheese, coconut, marshmallows and baked goods are a few examples of foods that rely on humectants. Humectants also are used in military and space technology to allow foods such as meat to be stored without refrigeration for longer periods of time.

Sugar and salt are the oldest and most widely used humectants. Examples of other commonly used humectants include glycerin, honey, sugar alcohols, glucose syrup, egg yolk, egg white, molasses and alpha hydroxy acids such as lactic acid.

Anticaking Agents

Fine-particle solids such as dry milk powder, flour, baking powder, cake mixes and powdered sugar are a few foods that benefit from anticaking agents, which prevent the formation of lumps and keep the products flowing freely. Without them, coffee powders in vending machines would not function properly and foods like grated cheese could form clumps and become sticky.

Most anticaking agents are made from synthetic substances such as silicon dioxide, magnesium carbonate and iron ammonium citrate. Calcium silicate, commonly added to table salt, absorbs both oil and water. Natural anticaking agents include magnesium silicate and corn starch.


Humectants and anticaking agents are direct food additives that must be approved before use by the U.S. Food and Drug Administration. Assessment of a food substance includes an evaluation of its safety and functionality, including all studies on its stability, purity, potency, performance and usefulness.

Additive standards are defined with strict criteria, including safety, lack of adverse odors and flavors, and documented need of use before approval is granted. Maximum usage levels vary depending on the additive and food in which it is used. For example, silicon dioxide used in shredded cheese and powdered mixes has a limit of 2 percent by weight of the food.

Recently, a few government rulings have changed the status of anticaking agents and humectants. The new ruling removes partially hydrogenated oils, used as an anticaking agent, from the “Generally Recognized as Safe” list and gives manufacturers until the summer of 2018 to remove it from their products.


People sensitive to humectants, especially when ingested in large amounts, may suffer from nausea or diarrhea. Sugar alcohols in large doses may have a laxative effect.

Humectants and anticaking agents continue to be active areas of research and development in an effort to discover safe, natural alternatives and emerging technologies that can offer additional benefits to our food supply and the planet.

Final Thought

Humectants and anticaking agents are used in very small amounts to safeguard the food supply and maintain quality during shelf life. Extensive research and testing have deemed these additives safe in approved amounts. However, anyone with questions about food additives can consult a registered dietitian nutritionist.

Kathleen Zelman
Kathleen Zelman, MPH, RDN, is the nutrition director of WebMD.