Emulsions
Mayonnaise
Mayonnaise · Cold, thick oil‑in‑water emulsion primarily stabilized by egg yolk, with acid, seasoning, and dispersed vegetable oil. The classic French mother sauce from which many derivatives (aioli, rouille, rémoulade) are built.
The formula
1 yolk (≈20 g) + 15–20 g acid : 200–250 g oil
Scale by weight: 1 yolk emulsifies up to ~750 ml oil; typical home batch uses 1 yolk, 250 g oil, 15–20 g acid, 1–2 g salt. Yields ≈280 g sauce. For larger batches, keep yolk:oil ≈1:10 by weight.
Identity
- Raw egg yolk is the primary emulsifier (lecithin and protein)
- Oil is the dispersed phase, added slowly to form fine droplets
- Acid (lemon juice or vinegar) provides flavor and lowers pH to stabilize proteins
- Salt enhances flavor and assists protein hydration
- Optional mustard acts as a secondary emulsifier and flavor base
Ingredients
| Binder | Egg yolk (large) | Provides lecithin and proteins that coat oil droplets. |
| Fat | Neutral vegetable oil (e.g., sunflower, grapeseed, light olive) | Dispersed phase; should be at room temperature. |
| Acid | Lemon juice or white wine vinegar | Typical 15–20 g per yolk; adjust to taste. |
| Seasoning | Fine sea salt | 1–2 g per batch; dissolves in aqueous phase. |
| Aromatics | Dijon mustard (optional) | Acts as secondary emulsifier; ~½ tsp per yolk. |
Method
- 1Combine yolk, mustard (if using), acid, and salt in a wide bowl or the base of a mortar.Creates a homogeneous aqueous phase and begins protein hydration.
- 2Whisk vigorously while adding oil in a very thin, steady stream, starting dropwise.Gradual incorporation prevents large oil droplets and allows the yolk’s emulsifiers to coat each droplet as it forms.
- 3Once the mixture thickens and the emulsion is stable (after ~50 g oil), increase oil flow to a thin but continuous stream while still whisking constantly.Continued whisking incorporates more oil quickly without breaking the emulsion.
- 4Continue until all oil is added and the sauce is glossy, thick, and holds its shape.Full incorporation yields the characteristic creamy texture and maximum viscosity.
- 5Taste and adjust seasoning, acidity, or consistency; thin with a few drops of water or acid if needed.Fine‑tunes flavor balance and texture after the emulsion is complete.
Techniques that matter
Emulsification (oil‑in‑water)
The yolk’s lecithin and proteins adsorb to oil droplets, preventing coalescence and creating a stable colloidal suspension.
Controlled oil addition
Ensures small droplet size and continuous emulsifier coverage; too fast a pour causes immediate phase separation.
Temperature management
Cold ingredients (especially yolk) help keep the emulsion thick and reduce risk of curdling; oil should be room temperature to avoid shocking the yolk.
Variations & derivatives
AïoliProvençal (France)
Garlic‑flavored mayonnaise; garlic crushed with yolk before emulsifying oil.
RouilleProvençal (France)
Spicy mayonnaise with red pepper, garlic, and often used on fish soups.
RémouladeFrench
Mayonnaise seasoned with mustard, capers, pickles, and herbs.
Chipotle mayoUnited States/Mexico
Mayonnaise blended with pureed chipotle peppers for smoky heat.
Greek‑style yogurt mayoInternational
Replace up to half the oil with thick Greek yogurt for a lighter, tangier sauce.
Used in these dishes
Substitutions
- Egg yolk → Aquafaba (chickpea water) or commercial egg‑free emulsifier (e.g., soy lecithin) — Use 1 Tbsp aquafaba per 250 ml oil; texture will be lighter; safe for vegans.changes result
- Lemon juice → White wine vinegar or apple cider vinegar — Flavor shifts slightly but acidity is comparable; safe substitution.
- Neutral oil → Melted, slightly cooled butter or avocado oil — Butter adds richness but can reduce emulsion stability; avocado oil maintains neutral flavor.changes result
Troubleshooting
Sauce breaks (oil separates, curdled appearance)
Oil added too quickly, temperature shock (cold oil on warm yolk), or insufficient emulsifier. → Start fresh with another yolk in a clean bowl; slowly whisk the broken sauce into the new yolk as if adding oil, or add a teaspoon of mustard and a splash of water while whisking vigorously.
Mayonnaise is too thick or stiff
Excess oil relative to yolk or over‑whisking after full incorporation. → Thin by whisking in 1 tsp of cold water or acid at a time until desired consistency.
Mayonnaise tastes flat or lacking acidity
Insufficient acid or salt. → Add lemon juice or vinegar gradually, tasting until balanced; finish with a pinch of salt.
Sauce is greasy or oily on the palate
Incomplete emulsification (large oil droplets) or too much oil. → Re‑emulsify by adding a small amount of yolk or mustard and whisking vigorously while slowly drizzling in the excess oil.