Ethoxylated Mono and Diglycerides
What are Ethoxylated Mono and Diglycerides?
Ethoxylated mono and diglycerides (EMG) are emulsifiers, produced by an interaction between glycerides and ethylene oxide. The two are some of the oldest and widely used food emulsifiers, derived from the glycerol found in plant oils and animal fat.1 Their dough strengthening properties are strong, so they are popular for crusty breads with a chewy texture. However, they are found in biscuits, coffee whiteners, ice cream, and salad dressings as well. They also improve shelf life for baked goods. Their HLB value falls between 9 and 10.
How they Work ?
Small amounts of mono and diacylglycerols are extracted from natural fats oils, with a hydrolysis reaction. They are then added to ethylene oxide, which turns the mono and diglycerides into a surfactant.2 When added to a recipe, it will help lower tension between two liquids or a liquid and a solid, working as an emulsifier. Monoacylglycerols have two free hydroxyl groups and have stronger surface activity compared to diacylgyercols.
There are two common ways these ethoxylated glycerides are commercially produced. Normal alkaline catalysts are used in the process.3 One way is a direct esterification of glycerol with a fatty acid. Another is glycerolysis of natural or hydrogenated fats or oils. While either option will produce roughly the same end result, glycerolysis is a less expensive option as fats are cheaper than fatty acids.1
Vegetable oils or animal fats are usually used in the production, and an alkaline catalyst added at high temperatures creates a blend of mono and diglycerides.
EMG typically are sold as glycerin flakes. They must be dissolved in oil, compared to most ingredients that can be mixed with water. The oil must be at a temperature above 60 degrees C or 140 degrees F to be easily mixed in. When used as an emulsifier, 0.5 to 2 percent mono and diglycerides is best.
In bread products, glycerides have strong hydrophilic surfactant properties and will improve gluten elasticity and extensibility. They will also produce a greater loaf volume with a finer crumb. However, when too much is added to the recipe will cause an open and irregular cell structure. The water solubilization in oil that takes place during microemulsions decreases with the increasing of ethoxylated content in mixed surfactants.4
EMG can also be listed as polyglycerate 60 labels. However, “mono-and diglycerides of fatty acids” or “ethoxylated mono- and diglycerides” must follow it.
The FDA has regulations of the levels of ethoxylated mono and diglycerides used as an emulsifier, pan release agent, toppings, icings, and frozen foods, so be sure to check all the requirements at fda.gov.
1. Gooch, Jan W. “Glycerides.” Encyclopedic Dictionary of Polymers. New York, NY: Springer, 2007. N.
2. Hasenhuettl, Gerard L., and Richard W. Hartel. Food Emulsifiers and Their Applications. New York: Chapman & Hall, 1997.
3. 2. Texter, J. Reactions and Synthesis in Surfactant Systems. New York: Marcel Dekker, 2001. 19-20.
4. Fanun, Monzer. “Reprint of “Properties of Microemulsions with Mixed Nonionic Surfactants and Citrus Oil”.” Colloids and Surfaces A: Physicochemical and Engineering Aspects 382.1-3 (2011): 226-31.