Aioli seems to be one of the hottest condiments in restaurants across the country, but is it just a fancy name for mayonnaise? Unfortunately, in many places the two have become synonymous. Although many restaurants tout aioli on menus when simply using flavored mayonnaise, there is a legitimate difference between the two spreads. When we take a closer look at the composition of each spread, the differences and similarities become clear.
Mayonnaise is an emulsion created with egg yolk and oil. When oil is slowly added to egg yolk while while vigorously beating, the oil breaks up into tiny droplets that then get suspended within the egg yolk. Thousands of tiny droplets of oil create the creamy, opaque color of mayonnaise in contrast to the clear appearance of oil. Lecithin in the egg yolk acts to keep the droplets suspended instead of the oil separating out and regrouping like it normally would.
Mayonnaise typically uses a neutral, flavorless oil, like canola. It sometimes has an acidic ingredient, like lemon juice or vinegar, added to provide tartness and a slight contrast to the smooth oil. Salt, white pepper, and dry mustard powder are also common ingredients in mayonnaise, although just about anything can be added.
True aioli is an emulsion created with just garlic and extra virgin olive oil. In fact, the name aioli translates to "garlic oil." Garlic does not have strong emulsifying properties like egg yolk, so it takes a great deal of elbow grease to emulsify olive oil into the garlic, especially when using a mortar and pestle as in the traditional method of preparation.
Sometimes other ingredients are added to help the garlic and olive oil emulsify faster. Bread is a common emulsifier, as is egg yolk, which is where the similarities between aioli and mayonnaise begin to appear. Even when egg yolk is included in aioli, it still differs greatly from mayonnaise because of the strong garlic flavor and the use of extra virgin olive oil, which has a distinct flavor of its own.
Each sauce has many variations, which causes a lot of confusion for those with little culinary knowledge. You can have garlic flavored mayonnaise that differs from aioli because it is made with a neutral oil, or an olive oil mayonnaise that isn't quite aioli because it doesn't contain garlic. One thing is for sure, though, when you see aioli on a menu, you're going to get a creamy oil emulsion spread. Whether it's a true aioli or simply a mayonnaise dressed to impress is the chef's secret.