Mayonnaise (often abbreviated to mayo) is a thick condiment. White or yellowish-white in color, it is a stable emulsion of oil, salt, and vinegar or lemon juice which uses egg yolks as an emulsifier. In France, sometimes mustard is added as a flavoring, whereas in Spain it is made using the same ingredients, but specifically olive oil as the oil, and never with mustard. Numerous other sauces can be created from it by adding additional seasonings.//
There are a number of different explanations for the origin of the term mayonnaise.
The most probable origin of mayonnaise is that the recipe was brought back to France from the town of Mahon in Menorca, after Louis-FranÃ§ois-Armand du Plessis de Richelieu's victory over the British at the city's port in 1756. According to this version, the sauce was originally known as salsa mahonesa (as it is still known on Menorca), later becoming mayonnaise as it was popularized by the French.
The French Larousse Gastronomique 1961 suggests: ``Mayonnaise, in our view, is a popular corruption of moyeunaise, derived from the very old French word moyeu, which means yolk of egg.``  The sauce may have been christened mayennaise after Charles de Lorraine, duke of Mayenne, because he took the time to finish his meal of chicken with cold sauce before being defeated in the Battle of Arques.
Nineteenth-century culinary writer Pierre Lacam suggested that in 1459, a London woman named Annamarie Turcauht stumbled upon this condiment after trying to create a custard of some sort.
According to Trutter et al.: ``It is highly probable that wherever olive oil existed, a simple preparation of oil and egg came about â€“ particularly in the Mediterranean region, where aioli (oil and garlic) is made.``
According to the Oxford English Dictionary, mayonnaise made its English language debut in a cookbook of 1841.
Mayonnaise can be made by hand with a mortar and pestle, whisk or fork, or with the aid of an electric mixer, an electric blender, or a food processor. Mayonnaise is made by slowly adding oil to an egg yolk, while whisking vigorously to disperse the oil. The oil and the water in yolks form a base of the emulsion, while the lecithin from the yolks is the emulsifier that stabilizes it. Additionally, a bit of a mustard may also be added to sharpen its taste, and further stabilize the emulsion. Mustard contains small amounts of lecithin.
The traditional European recipe is essentially the same as the basic one described above, but it uses top-quality olive oil and sometimes vinegar or lemon juice. Some nouvelle cuisine recipes specify safflower oil. It is considered essential to constantly beat the mayonnaise using a mortar and pestle or whisk while adding the olive oil a drop at a time, in order to fully incorporate the oil into the emulsion. Experienced cooks can judge when the mayonnaise is done by the emulsion's resistance to the beating action. Mayonnaise made this way may taste strong or sharp to people accustomed to commercial products.
Homemade mayonnaise can approach 85% fat before the emulsion breaks down; commercial mayonnaises are more typically 70-80% fat. ``Low fat`` mayonnaise products contain starches, cellulose gel, or other ingredients to simulate the texture of real mayonnaise.
Some homemade recipes use the whole egg, including the white. It can also be made using solely egg whites, with no yolks at all, if it is done at high speed in a food processor. The resulting texture appears to be the same, andâ€”if seasoned, for example, with salt, pepper, mustard, lemon juice, vinegar, and a little paprikaâ€”the taste is similar to traditional mayonnaise made with egg yolks..
Commercial producers either pasteurize the yolks, freeze them and substitute water for most of their liquid, or use other emulsifiers. For homemade mayonnaise it is recommended to use the freshest eggs possible. Some stores sell pasteurized eggs for home use. The eggs can also be coddled in 170 Â°F (77 Â°C) water, after which the hot yolks, now slightly cooked, are removed from the whites. Homemade mayonnaise will generally only keep under refrigeration for three to four days.
Commercial mayonnaise, due to the addition of acids like vinegar or lemon juice, has a pH between 3.8 and 4.6, making it an acidic food. There is a misconception that foods like potato salad can make a person sick if left out in the sun, due to the mayonnaise spoiling. This is false; the pH of mayonnaise prevents harmful bacteria from growing in it. Left out of refrigeration, mayonnaise will develop an unappetizing taste and smell, due to other types of bacteria and molds that can spoil it; but will not make one sick.
Worldwide, mayonnaise is commonly served in a sandwich, or with salad such as potato salad or canned tuna (``tuna mayo`` or tuna salad). Regional uses are listed below:
In Western Europe, mayonnaise is often served with pommes frites (French fries or chips), especially in Belgium and The Netherlands. It is also served with cold chicken or hard-boiled eggs in France, the UK, The Netherlands, Russia, Poland, Lithuania, and Ukraine.
Guidelines issued in September 1991 by Europe's Federation of the Condiment Sauce Industries recommend that oil and liquid egg yolk levels in mayonnaise should be at least 70% and 5% respectively, although this is not legislated. Most available brands easily exceed this target.
Commercial mayonnaise sold in jars originated in New York City, in Manhattan's Upper West Side. In 1905, the first ready-made mayonnaise was sold by a family from Vetschau, Germany, at