The short answer: mayonnaise is an emulsion of egg, oil and an acid such as lemon or vinegar. Traditional aioli is garlic and olive oil, with salt, and no egg. What most restaurants outside the Mediterranean sell as “aioli” is garlic mayonnaise. It is a good sauce, but it is a different one.
We cook Catalan maritime cuisine in Barcelona’s Poblenou, so this question reaches our tables more often than you would think. Here is how the two sauces differ, where each comes from, how to read a menu, and what to do when someone tells you the difference doesn’t matter.
TL;DR
- Mayonnaise = egg yolk + oil + lemon or vinegar. Pale yellow, smooth, mild.
- Traditional aioli (alioli, allioli) = garlic + olive oil + salt, made by hand in a mortar. Opaque white, dense, pungent. No egg.
- Garlic mayo = mayonnaise with garlic added. Many menus label it “aioli”, especially in the US and UK, and that is where the confusion comes from.
- Egg-based versions of aioli exist and are common, but purists in Catalonia and Provence do not count them as the original.
- On a menu in Spain, ask whether the alioli is made with or without egg. A good kitchen will answer without hesitation.
Table of Contents
- The difference in one table
- What mayonnaise is
- What aioli is
- Aioli vs garlic mayo
- Where each sauce comes from
- How to tell what you are being served
- When to use which
- Making aioli at home: a realistic guide
- Our perspective at Els Pescadors
- Taste Catalan seafood in Poblenou
- A short word on spelling and pronunciation
- FAQ
- Sources
The difference in one table
| Mayonnaise | Traditional aioli | Garlic mayo | |
|---|---|---|---|
| Core ingredients | Egg yolk, oil, lemon juice or vinegar | Garlic, olive oil, salt | Mayonnaise plus garlic |
| Egg | Always | None | Always |
| What holds it together | Egg yolk, stabilized by acid | Crushed garlic, sometimes a little bread or potato, and slow work | Egg yolk |
| Color | Pale yellow to cream | Opaque white | Pale yellow, often with green or brown flecks |
| Flavor | Mild, tangy | Sharp, garlicky, olive-oil forward | Mild with a garlic note |
| Method | Whisk or blender | Mortar and pestle, oil added drop by drop | Stir garlic into mayo, or blend |
| Effort | Low | High | Very low |
The table is a simplification, as every kitchen has its own habits. But it explains most of the arguments you will hear.
What mayonnaise is
Mayonnaise is a cold emulsion: tiny droplets of oil suspended in a water-based liquid, in this case the egg yolk and the lemon juice or vinegar. The yolk does the emulsifying and the acid adds flavor and helps keep the sauce stable. You add oil slowly while whisking, and the mixture thickens. Because the base is neutral, mayonnaise is a blank canvas: add mustard, herbs, saffron, chili or garlic and you get a family of sauces.
That neutrality is why mayo is so widely used. It is a sauce for sandwiches, potato salad, fried fish and cold lobster, and it rarely competes with what it accompanies.
What aioli is
The name is the recipe. The word comes from the Catalan all (garlic) and oli (oil), and the Spanish Royal Academy’s dictionary of doubts defines alioli as a sauce made from oil and garlic, noting that it is a spelling adaptation of the Catalan allioli. Garlic and oil: that is the whole definition.
The classic method is the one Catalan home cooks still use. Put a pinch of salt and some garlic in a mortar, crush them well, then add the oil little by little in a thin thread. The garlic paste carries the emulsion, and a patient hand does the rest. Spanish television chef Joseba Arguiñano makes the same point in his egg-free recipe, which insists the traditional sauce takes no egg and needs only garlic, olive oil and salt.
The result looks different too. Egg-free aioli is opaque white and dense, almost like a paste, while versions with yolk turn yellow and resemble mayonnaise, as the French food magazine 180°C explains in its piece on the Provençal tradition.
Why the texture is different
Mayonnaise gets its structure from lecithin in the yolk. Traditional aioli has no yolk, so its structure comes from garlic that has been crushed to a fine paste, sometimes helped by a little bread or boiled potato, and from the speed at which you add the oil. That is why it is harder to make. Add the oil too fast and the sauce splits into a greasy puddle. The usual rescue is to start again in a clean bowl with a little warm water or a spoonful of a fresh emulsion and work the broken sauce back in slowly, a technique described by the Catalan site Aeic.
Aioli vs garlic mayo
This is the comparison most people actually mean. Garlic mayo is mayonnaise (egg, oil, acid) with garlic stirred or blended in. It takes two minutes, keeps well, and is stable even for cooks who have never touched a mortar. Nothing is wrong with it. It is just not aioli in the traditional sense.
The confusion has a practical cause. Menus in many countries use “aioli” as shorthand for any flavored mayonnaise: chipotle aioli, truffle aioli, lemon aioli, sriracha aioli. None of these contain the two ingredients the word names. Experts quoted in the 180°C article describe the garlic mayo served in many restaurants as a convenient shortcut, not the labor-intensive original.
There is also a middle ground worth knowing. Many cooks, including plenty in Catalonia and Provence, add an egg yolk to aioli to make it easier and more stable. The same source describes this as a common version while noting that Provençal purists will not accept it as the true sauce. If you are reading a menu, “aioli with egg” is honest and delicious, just closer to a strongly garlicked mayonnaise.
Where each sauce comes from
Aioli: a Mediterranean word with a long record
The term is Catalan in origin. The Royal Academy’s historical dictionary and its Diccionario panhispánico de dudas trace it to Catalan, and the dictionary entry places the first written records as early as 1024. It then travelled: into Provençal and French as aïoli, and into Spanish as alioli. In Provence it became a symbol of regional identity, and Slate.fr’s piece on the true recipe shows how seriously the French take the quantity of garlic and the method.
Mayonnaise: a rivalry between Spain and France
Mayonnaise has a more contested birth. The popular story ties it to the capture of Mahón, in Menorca, by French forces in 1756, with the Duke of Richelieu’s cook supposedly improvising the sauce. ABC’s cultural section reviews the debate and notes that a sauce appears in the Spanish cookbook Nuevo arte de cocina as early as 1745. The spelling itself is a flag: in French it is mayonnaise, and in Spanish you will see both mayonesa and mahonesa, the latter pointing to Mahón. Historians such as Pep Pelfort of the Institut Menorquí treat the debate as a proxy for an older Spain-France rivalry.
The practical conclusion: mayonnaise has a disputed origin, aioli has a clear linguistic one. And in Spain you can order either without anyone raising an eyebrow, because both are part of the everyday table.
How to tell what you are being served
You do not need a lab. These checks work in a Barcelona restaurant or anywhere else:
- Look at the color. Opaque, matte white points to egg-free aioli. A pale yellow, glossy sauce is made with yolk.
- Taste for garlic first. In real aioli, garlic arrives immediately and lingers. In garlic mayo, you taste creaminess first and garlic second.
- Check the texture. Egg-free aioli is dense and clings to the spoon. Mayo-based sauces are softer and more spreadable.
- Read the name. “Chipotle aioli”, “truffle aioli” and “sriracha aioli” are flavored mayonnaises by definition.
- Ask. In Spain, “¿El alioli lleva huevo?” is a normal question. Ask it, and you will usually get an honest answer.
One practical note on eggs: if you are pregnant, elderly or serving someone with an egg allergy, ask the kitchen whether the sauce contains raw egg. Allergies in particular are a question for the restaurant and your doctor, not for a food blog.
When to use which
Reach for mayonnaise when you want richness without personality: sandwiches, burgers, potato salad, a base for tartar sauce or a quick dip.
Reach for aioli when the sauce is part of the dish. In Catalan cooking it goes with grilled fish and shellfish, with boiled vegetables and potatoes, with grilled meats, and it is stirred into some rice dishes and stews. Its sharpness cuts through oily or salty food and it stands up to strongly flavored seafood.
Reach for garlic mayo when you want the effect of aioli with the convenience of mayonnaise, as long as you call it what it is.
Pairing it with seafood
Seafood and aioli have an old partnership on the Mediterranean coast. Garlic and olive oil are what fishermen and their families had on hand, and the sauce works because it is assertive without hiding the fish. A simple grilled fish with a spoonful of aioli and a squeeze of lemon needs nothing else. If you want to explore this tradition, our guides to traditional Spanish seafood dishes and authentic Catalan flavors and must-try Mediterranean seafood dishes are good places to start.
Making aioli at home: a realistic guide
The Arguiñano recipe on Hogarmanía works with two cloves of garlic, a pinch of salt and 100 ml of extra virgin olive oil, as listed on the recipe page. The principles below apply to any egg-free version.
- Start with a mortar. Peel the garlic and chop it roughly. Add salt, which acts as an abrasive, and crush to a smooth paste. The finer the paste, the better the emulsion.
- Add the oil in a thread. First by the drop, then in a very thin stream, while turning the pestle in one direction.
- Be patient. If the sauce starts to look oily and loose, stop adding oil and keep working until it comes together again.
- Season at the end. A little more salt, nothing else. Some cooks add a few drops of lemon, which is a choice, not a rule.
- If it splits, start over in a clean bowl and add the broken sauce slowly to a spoonful of warm water, as described by Aeic.
Choose a mild olive oil. A very bitter, peppery oil can make a raw emulsion taste harsh. This is our kitchen advice rather than a rule from a source, so adjust to your palate.
Our perspective at Els Pescadors
We work every day with a short list of ingredients: the morning’s catch, rice, olive oil, garlic, seasonal produce. Our cooking is built on the idea that when the product is good, sauces should support it, not cover it. That is why the aioli question matters to us.
We think the useful way to approach the debate is not to say one sauce is better. Mayonnaise and garlic mayo are fine sauces with their own place. What we ask is that names mean something. When a diner orders alioli in Catalonia, they are asking for a particular tradition, one tied to the coast, the mortar and the kitchen table. Honoring that tradition means knowing what goes into it and being honest about it when you cook or serve it.
Our approach to the menu follows the same principle: seasonal, local, honest. If you want to understand how we think about this, read why the morning catch shapes a Catalan maritime menu, or our overview of why traditional maritime cuisine is Barcelona’s best dining choice. If you have a question about how a sauce is prepared, or an allergy, tell our team when you book and we will answer it directly.
— YellowRock
Taste Catalan seafood in Poblenou
If this made you curious about how garlic, olive oil and the day’s fish come together on a plate, come and eat with us in Plaça de Prim. Our Menú de Temporada is 39 € per person and shows the season’s produce and catch. If you prefer to choose dish by dish, see La Carta, or look at our Menú Degustación for a longer meal. Tell us about any allergies or dietary needs when you reserve.
A short word on spelling and pronunciation
Spelling trips people up. In Catalan it is allioli (written “all i oli” in older texts), in Spanish alioli, in French aïoli, and in English most people write aioli. The three syllables are pronounced ai-o-li, roughly [ajɔˈli], as the Duden dictionary notes. The Duden also traces the word to Provençal, from ai (garlic) and oli (oil), which confirms the same logic across languages.
For mayonnaise, Spanish allows mayonesa and mahonesa. Both are correct, and the second is a nod to Mahón.
FAQ
Is aioli just mayonnaise with garlic?
Not in its traditional form. Traditional aioli contains only garlic, olive oil and salt, and has no egg. Garlic mayonnaise is mayonnaise with garlic added, and it is what many restaurants outside the Mediterranean call aioli. Both are tasty, but they are made differently and taste different.
Does aioli always contain egg?
No. The traditional Catalan and Provençal versions are egg-free. Many modern recipes add an egg yolk for easier emulsifying and a texture closer to mayonnaise. If it matters to you, whether for allergy, diet or tradition, ask the kitchen.
Can I substitute mayonnaise for aioli in a recipe?
Yes, in most cases. Stir in finely grated or crushed garlic and a little lemon, and let it rest for a few minutes so the garlic flavor develops. You will get a milder, creamier sauce than real aioli, so use less of it if you want to avoid overpowering a delicate fish.
What is the Catalan name for aioli?
It is allioli, from all (garlic) and oli (oil). Spanish spells it alioli, as defined by the Royal Spanish Academy, and you will see both on menus in Barcelona.
Why does my homemade aioli split?
Usually because the oil went in too fast or the garlic was not crushed finely enough. Add oil in a thin thread, especially at the start. If it separates, begin again in a clean bowl and slowly work the split sauce into a spoonful of warm water.
Sources
- alioli | Diccionario panhispánico de dudas, RAE
- ¿Mayonesa o mahonesa? El gran debate histórico, ABC
- Faites l’aïoli, pas la guerre, 180°C
- La vraie recette de l’aïoli, Slate.fr
- El origen del all i oli, Aeic
- Alioli sin huevo, receta de Joseba Arguiñano, Hogarmanía
- Aioli, Duden
