In the culinary arts, an emulsion is a mixture of two liquids that would ordinarily not mix together, like oil and vinegar. There are three kinds of emulsions:temporary, semi-permanent, and permanent. An example of a temporary emulsion is a simple vinaigrette while mayonnaise is a permanent emulsion.
An emulsion can be hot or cold and take on any flavor from sweet to savory; it can be smooth or have a bit of texture. No matter the type of emulsion, these dressings and sauces enhance the taste of the dish, bringing another level of flavor to foods such as salads and eggs. But what is truly interesting about emulsions is how the liquids blend together and make a thick consistency.
When you look at oil and vinegar separately, you wouldn't necessarily imagine they could become unified into a viscous liquid. But certain substances act as emulsifiers, which means they help the two liquids come together and stay together (either temporarily or permanently) when the mixture is agitated. In the case of mayonnaise and hollandaise, it's the lecithin in the egg yolks that acts as the emulsifier. Lecithin, a fatty substance that is soluble in both fat and water, will readily combine with both the egg yolk and the oil or butter, essentially holding the two liquids together permanently.
In a stable emulsion, the droplets of one of the liquids become evenly dispersed within the other liquid. The resulting liquid is thicker than the two original liquids were. In the case of salad dressing, oil droplets are suspended within the vinegar. As this vinaigrette sits, however, the oil and vinegar will separate again, making this a temporary emulsion.
A fine powder can help to stabilize an emulsion and so can a starch. That's why a roux is useful in thickening sauces; it's the starch in the flour that joins the butter to the liquid stock. A cornstarch slurry works the same way as does the technique known as monter au beurre, which is essentially a variation onliaison finalethat involves stirring raw butter into a sauce right before serving it; the fat droplets form an emulsion with the liquid in the sauce.
Temporary
A temporary emulsion is one that will separate in under an hour. It will emulsify again with some sort of agitation such as shaking or whisking. A salad dressing is a temporary emulsion—the oil and vinegar are poured into a jar and agitated until they come together as a unified liquid. The consistency will change, becoming thicker, and the color will be a melding of the two ingredients. Once the vinaigrette sits for a while, however, the oil and vinegar will start to separate. A simple shake or whisk will emulsify again.
Semi-Permanent
If the emulsion is maintained for a few hours before separating, it is considered semi-permanent. Hollandaise sauce is a semi-permanent emulsion; it is made of egg yolks and clarified butter. Clarified butter, which is pure fat, is best for forming the emulsion versus whole butter; whole butter contains around 15 percent water and this water can destabilize the emulsion. A hollandaise sauce will be stable longer than a vinaigrette, but it is recommended that you serve the sauce immediately.
Permanent
A permanent emulsion is one that will remain unified in its thickened state for an extended period of time. Mayonnaise is an example of a permanent emulsion, consisting of egg yolks and oil. Egg yolks and oil would not naturally come together, but when the oil is slowly whisked into the egg yolks, the two liquids form a stable emulsion that won't separate. If the oil is added too quickly or if the mixture is not agitated properly, the egg and oil will not come together and will fail to emulsify.
Surprising Foods That are Emulsified
One less obvious example of a food that is an emulsion is chocolate, whichis an emulsion of milk and cocoa butter. In fact, milk itself is an emulsion of water, protein solids, and butterfat. If you've ever added lemon juice to milk or boiled it you've seen what curdled milk looks like. Curdling is the breaking of the emulsion, which causes the protein solids to coagulate and separate from the liquid.
Another surprising example of an emulsion iscertain types of sausages and forcemeats. Hot dogs are an emulsified sausage where meat, fat, and water are combined to form a smooth filling which is then stuffed into a casing.
Make an Emulsified Beurre Rogue (Red Butter) Sauce
FAQs
Emulsion is the mixture of two or more liquids that do not naturally mix together. A classic example of emulsion in cooking the mixture oil and vinegar to make a simple vinaigrette. There are two types of emulsion, temporary and permanent.
What is emulsion in culinary? ›
In the culinary arts, an emulsion is a mixture of two liquids that would ordinarily not mix together, like oil and vinegar. There are three kinds of emulsions: temporary, semi-permanent, and permanent.
What are examples of emulsions in food? ›
Examples of Naturally Occurring Emulsions
Some examples include olive oil-in-vinegar salad dressing, mayonnaise, custard, eggnog, cream sauces, hollandaise sauce, ice cream, puddings, butter, and quark cheese.
What is an example of an emulsion? ›
Emulsion is a colloidal solution where both dispersed phase and dispersed medium are liquids. Examples are: Milk, face cream,etc.
What does emulsify mean in culinary? ›
To emulsify means to combine two ingredients together which do not ordinarily mix easily. The ingredients are usually a fat or an oil, like olive oil, and a water-based liquid like broth, vinegar, or water itself.
What is the definition of an emulsion? ›
An emulsion is a mixture of two or more liquids that are usually immiscible but, under specific transforming processes, will adopt a macroscopic hom*ogeneous aspect and a microscopic heterogeneous one. In an emulsion, one liquid is dispersed in the other.
What is emulsion in art? ›
A uniform mixture of oily substances and watery substances, which do not ordinarily mix. Artists may add an emulsifier, like egg yolk, to such emulsions as oil paint and water in order to encourage mixing and stabilization.
What is the most common emulsion? ›
Common emulsions can be oil suspended in water or aqueous phase (o/w) or water suspended in oil (w/o). There also can be more complex systems, such as oil in water in oil (o/w/o).
What is emulsification in simple terms? ›
Emulsification is the process by which the dispersed phase is broken up into small droplets. Normally a coarse premix is created by rapid mixing of the ingredients. This is sufficient to break up the dispersed phase into large droplets, and allow adsorption of the emulsifiers prior to final emulsification.
How do you identify an emulsion? ›
The colloidal dispersion of two non-miscible liquids is known as an emulsion. The methods to identify them include dilution test, conductivity test, and dye solubility test.
To create a successful emulsion, you need two things: an emulsifier, and force. Force—usually in the form of whisking or blending—breaks apart the oil, dispersing it through the surrounding liquid; the emulsifier keeps it from retreating back into itself.
What foods do you emulsify? ›
Emulsifiers are added to processed foods like mayonnaise, ice cream, chocolates, peanut butter, cookies, creamy sauces, margarine, and baked goods to prevent the separation of their oil and water components. Emulsifiers also give these foods a smooth texture and increase their shelf life.
What are good emulsifiers for cooking? ›
“Emulsifiers” can help you produce a nicer, longer-lasting emulsion. The good news is that there are many common emulsifiers readily available to the home cook. A few of the most common are mustard (either prepared or powder), egg yolk, garlic paste and tomato paste.
What makes a sauce an emulsion? ›
What is an emulsified sauce? Emulsion sauces are made by mixing two ingredients that don't easily mix together (that's why these sauces can often separate). An emulsifying agent, usually egg, is used to combine the mixture.
What is emulsion on a menu? ›
An emulsion is a mixture of two liquids that are unmixable. Oil and vinegar, for example. A vinaigrette dressing is one of the simplest forms of emulsion in the kitchen. Most of the emulsions in cooking are of oil in water, where the oil droplets are suspended throughout the water.
What are 3 emulsion sauces? ›
Hollandaise, Béarnaise, and their derivatives make up a class of emulsion sauces that also includes the cold sauce mayonnaise.
What is an example of an emulsifier? ›
Some of the most common emulsifiers in food products include soy lecithin, carrageenan, mono- and diglycerides, carboxymethylcellulose, and polysorbate. Emulsifiers in skin care products include sodium lauryl sulfate (SLS), benzalkonium chloride, cetearyl alcohol, stearic acid, glyceryl stearate, and ceteareth-20.
